Nsf Standard For Drinking Water Treatment Units

Transcript

Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) This document is part of the NSF International Standards process and is for NSF Committee uses only. It shall not be reproduced, or circulated, or quoted, in whole or in part, outside of NSF activities, except with the approval of NSF. The language of this document has not been formally accepted for distribution by NSF and is under consideration at the task group level. NSF Standard for Drinking Water Treatment Units — Supplemental Microbiological Water Treatment Systems – Filtration 1 General 1.1 Purpose It is the purpose of this standard to establish minimum requirements for the reduction of microorganisms using mechanical filtration devices for supplemental treatment of microbiologically safe drinking water. Mechanical filtration devices covered by this standard are intended for use only on water supplies that have been treated to public water system standards or otherwise are determined to be microbiologically safe as demonstrated by routine testing and are intended only for protection against intermittent incursions or accidental microbiological contamination of otherwise safe drinking water. This standard also specifies the minimum product literature and labeling information that a manufacturer shall supply to authorized representatives and system owners as well as the minimum service-related obligations that the manufacturer shall extend to system owners. 1.2 Scope The point-of-use and point-of entry systems addressed by this standard are designed to be used for the supplemental microbial control of specific organisms that may occasionally be present in drinking water (public or private) because of intermittent incursions. Certain of these specific organisms that may be introduced into the drinking water are considered established or potential health hazards. This standard establishes requirements for point-of-use and point-of-entry drinking water treatment systems, and the materials and components used in these systems. 1.3 Minimum requirements This Standard establishes minimum requirements. Variations may be permitted when it is verified that compared to the systems covered in this Standard the alternate systems are as resistant to wear and physical damage or provide equivalent operation or performance. Systems with components or functions covered under other NSF or NSF/ANSI Standards or Criteria shall comply with those applicable requirements. 1.4 Alternate materials, designs and construction While specific materials, designs and construction may be stipulated in this Standard, systems that incorporate alternate materials, designs and construction may be acceptable when it is verified that such systems meet the applicable requirements stated herein. 1.5 Mechanical and microbial reduction performance claims 1 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) 1.5.1 All NSF/ANSI 244-3 performance claims shall be verified and substantiated by test data generated under the requirements of NSF/ANSI 244-3. 1.5.2 When making performance claims for substances not specifically addressed in the scope of this Standard or for those substances not specifically addressed but falling under the scope of NSF/ANSI 244-3 those claims not specifically addressed in the Standard shall be so identified. 1.5.3 Quality assurance requirements Manufacturers of devices claiming reduction capabilities for microbiological contaminants shall be required to demonstrate that the manufacturing process is capable of producing devices at least equivalent in performance to those devices tested and listed by the testing agency. This required demonstration shall be part of the manufacturing process, including compilation and retention for at least five years of supporting test data or other appropriate documentation. This information shall be made available for inspection at any time by the testing agency, their designate or any other certification or testing agency that the manufacturer has so authorized under mutual consent. Device manufacturers shall use good practices in manufacturing and each unit shall carry an identification code or other means of traceability, which allows determination of the date of manufacture and specific lots of components or raw materials used. 1.5.3.1 Devices Containing an Integral Performance Monitoring feature A sensor incorporated in each device, which monitors or assures the actual in-service microbiological device performance is an acceptable quality assurance demonstration feature in lieu of the Quality Assurance Requirements described above. However all units must carry identification codes as required above in 1.5.3. Sensors that measure the UV intensity in a UV unit or TDS leakage in a distiller are examples of such features that relate directly to the required performance. Similar innovative and properly validated monitoring technologies may be acceptable for mechanical reduction technologies. 1.5.3.2 Shelf life Manufacturers of integral devices and replacement components containing materials critical to performance that are susceptible to deterioration over time shall provide notification to the end user of a “DO NOT USE AFTER (DATE)” or similar notification or means of informing the user that the device or component may not function as claimed after a certain date or time. See 7.3.1 and 7.3.2. Information and data used to determine the shelf life of the device shall be part of the Quality Assurance Requirements in 1.5.3. 1.6 Standard review This Standard shall be reviewed at least once every five years. The NSF Joint Committee on Drinking Water Treatment Units shall conduct the review. 2 Normative references The following documents contain provisions that constitute requirements of this Standard. At the time of publication, the indicated editions were valid. All standards are subject to revision and parties are encouraged to investigate the possibility of applying the recent editions of the standards indicated below. APHA, Standard Methods for the Examination of Water and Wastewater, twentieth edition1 1 American Public Health Association (APHA), 800 I Street, NW, Washington, DC 20001 2 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) NSF/ANSI 42 –2004, Drinking water treatment units — Aesthetic effects NSF/ANSI 60 –2004, Drinking water treatment chemicals — Health effects NSF/ANSI 61 –2004, Drinking water system components — Health effects SAE Standard J726 – June 1993, Air Cleaner Test Code2 USEPA–100.1, Analytical Method for Determination of Asbestos Fibers in Water, formerly USEPA-600/4-83-0433 USEPA–600/4–79–020, Methods for the Chemical Analysis of Water and Wastes, March 19835 USEPA–600/4 – 91/010, Methods for the Determination of Metals in Environmental Samples, June 19935 USEPA–600/4 – 88/039, Methods for the Determination of Organic Compounds in Drinking Water, December 19885 USEPA–600/4 – 90/020, Methods for the Determination of Organic Compounds in Drinking Water – Supplement 1, July 19905 USEPA National Primary Drinking Water Regulations, 40 CFR Part 144 USEPA National Primary Drinking Water Regulations, 40 CFR Part 1366 USEPA National Secondary Drinking Water Regulations, 40 CFR Part 1436 USEPA ICR Protozoan Method for the Detecting Giardia Cysts and Cryptosporidium Oocysts in Water by a Fluorescent Antibody Procedure, EPA/814-B-95-003, June 19956 USFDA Code of Federal Regulations, Title 21, (Food and Drugs) Direct Food Additive Substances Parts 170 through 199, April 1, 19926 [Definitions to be moved out of this standard and placed in NSF/ANSI 330 - Glossary of Drinking Water Treatment Unit Terminology. NOTE: Four terms were found below that are not defined in Std 330. They are: 3.21 - end-of-life indicator; 3.40 – multiple technology challenge; 3.53 – replacement component; and, 3.58 – treatment train 3 Definitions The following terms are used in this document: 3.1 absorption: The physical process occurring when one substance actually penetrates into the structure of another substance, termed the absorbent. 3.2 accessible: Fabricated to be exposed for cleaning and inspection using simple tools (e.g., screwdriver, pliers, open-end wrench). 2 Society of Automotive Engineers, 400 Commonwealth Drive, Warrendale, PA 15096 3 U.S. Environmental Protection Agency (USEPA), Environmental Monitoring and Support Laboratory, Cincinnati, OH 45268 4 Superintendent of Documents, U.S. Government Printing Office, Washington, DC 20402 3 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) 3.3 active agent: A substance or medium added to or involved in the treatment process that requires direct or sacrificial release of the agent or degraded product to reduce specific contaminants in the water. 3.4 additive: A substance added to water, directly or indirectly, during a drinking water treatment process. 3.5 adsorption: The physical process occurring when liquids, gases, or dissolved or suspended matter adhere to the surface of, or in the pores of, an adsorbent medium. Adsorption is a physical process that occurs without chemical reaction. 3.6 advisory concentration: The minimum concentration attainable for a given substance using good manufacturing practices and appropriate process controls. In some cases, the advisory concentration is equal to the limit of detection of the preferred analytical method for the substance. 3.7 aesthetic: Pertaining to factors such as taste, odor, color, and appearance that affect drinking water and, therefore, may deter acceptance of public and private drinking water. 3.8 air gap: An unobstructed vertical distance of 2 pipe diameters or 25 mm (1 in), whichever is greater, through the free atmosphere between the outlet of the waste pipe and the flood level rim of the receptacle into which it is discharging. 3.9 backwash: The upflow or counter-current flow of water through a filter medium for the purpose of thoroughly expanding the media to remove foreign particulate matter accumulated during the service cycle and flushing it to the drain. 3.10 bed volume: Total water-holding volume of the media without components in place. 3.11 bypass: (verb) To flow around a water treatment system or its media. (noun) A valve system that allows water to flow around the water treatment system while the system is being regenerated or serviced. 3.12 capacity: The rated service cycle, expressed as a function of time or volume, of water treated by a system, between servicing of the media (cleaning, regeneration, or replacement), as specified by the manufacturer. 3.13 chemical reduction: The reduction in the quantity of one or more specified organic or inorganic contaminants in drinking water. 3.14 clean system: A unit that has not been subjected to an influent challenge containing the specified contaminant(s). 3.15 component: A separate or distinct part of a drinking water treatment system. 3.16 contaminant: Any undesirable physical, chemical, or microbiological substance in drinking water that may have an adverse health or aesthetic effect, or both. 3.17 cyst: The resistant stage in the life cycle of waterborne protozoa, which may be found in surface drinking water supplies, and includes oocysts of Cryptosporidium and Toxoplasma and cysts of Giardia and Entamoeba. 3.18 degradation product: A product of an active agent or additive that has been altered by biological, chemical, or physical interaction. 4 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) 3.19 disposable pressure vessel: A pressure vessel that is replaced at the end of each rated service cycle and has an estimated service life of one year or less. 3.20 drinking water: Water that is intended for human consumption. 3.21 end-of-life indicator: a device, means or method integral to the system that warns the user that the system’s period of operation has reached the manufacturer’s claimed effective usage time, life or capacity. [Add to Std 330. Suggest removing “integral”. An ELI could be nonintegral to a system.] 3.22 exposure water: Water having definitive characteristics, prior to contact with a system or component(s) in extraction procedures. 3.23 extractant water: Water that has been in contact with a system or component(s) for a specified duration. 3.24 fiber: organisms). A particle with a length three or more times the width or diameter (excludes 3.25 filter: (verb) To pass water containing particles through a semi-permeable material (e.g., charcoal, fabric, filament) to separate the particles from the water. (noun) A system for carrying out the process of filtration; it consists of the filter medium and suitable hardware for constraining and supporting the filter medium in the path of the water. 3.26 filter area: The effective area at which water first contacts the filter medium. 3.27 filter medium: The semi-permeable material used to separate particulate matter from water. 3.28 filtration: The process by which particles are separated from water by passing water through a permeable material. 3.29 time. flow rate: The volume of water that passes through a system in a specified amount of 3.30 influent challenge: The mixture of water and contaminants entering a system. 3.31 initial dynamic pressure: The pressure as measured at a pressure gauge immediately preceding connection to the system being tested (see figure 1) when the system is filled with water and flowing. 3.32 maximum contaminant concentration (MCC): The maximum permissible concentration of a contaminant in drinking water as established by a recognized regulatory agency, such as the USEPA or Health Canada. 3.33 maximum contaminant level (MCL): The maximum permissible concentration of a contaminant or substance in drinking water as established in the National Primary Drinking Water Regulations. 3.34 maximum drinking water level (MDWL): The maximum concentration of a contaminant or substance in drinking water that a system is allowed to contribute to the effluent, as established in this Standard. 3.35 mechanical filtration system: A system that mechanically separates particulate matter from water. 5 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) 3.36 medium (media): The selected material in a system that forms a water-permeable barrier to the passage of certain contaminants. 3.37 medium migration: The entrainment of a fraction of the medium into the effluent. 3.38 microbiologically safe water: Drinking water deemed acceptable for human consumption by an appropriate health or regulatory agency having jurisdiction. 3.39 microbiologically unsafe water: Water that (1) is known to bacteria, viruses, protozoa or other disease-causing microbiological positive test for an indicator organism, or (3) is determined unsafe by regulatory agency having jurisdiction or, (4) has not been shown to agency microbiological guidelines. contain disease causing agents or, (2) shows a an appropriate health or meet appropriate health 3.40 multiple technology challenge: The minimum average influent challenge concentration for an individual treatment technology within a treatment train as determined by the maximum effluent concentration of the prior treatment technology during evaluation. [Add to Std 330.] 3.41 open discharge system: A system not subject to line pressure during the off mode. 3.42 point-of-entry system: A system used to treat all or part of the water at the inlet to a residential facility (where the inlet connection is 32 mm [1-1/4 in] or less), or at a bottled water production facility employing mechanical filtration devices containing non-stacked filters (where the inlet connection may be greater than 25 mm [1 in]). 3.43 point-of-use system: A plumbed-in or faucet-mounted system used to treat the water at a single tap or multiple taps but not used to treat the water for the majority of the facility. A batch system is considered a point-of-use system. 3.44 pressure drop: The difference between the inlet and outlet pressures of a system at the rated service flow rate. 3.45 pressure vessel: A component of a system intended to hold water under pressure higher than the atmospheric pressure. 3.46 product water: Water that has been treated by the system. 3.47 rated service cycle: The capacity of a system expressed as a function of time, or volume of water to be treated, between cleaning replacement or regeneration of the media, as specified by the manufacturer. 3.48 rated service flow: The flow rate at which the system will deliver treated water of acceptable quality, as claimed by the manufacturer. Flow rate is expressed as liters (gallons) per minute, or liters (gallons) per day. 3.49 raw water: Untreated water or any influent water before it enters a specific water treatment component or system. 3.50 tools. readily accessible: Fabricated to be exposed for cleaning and inspection without using 3.51 readily (or easily) removable: Capable of being separated from the system without using tools. 3.52 regeneration: The maintenance process that restores the media to perform its water treatment function(s). 6 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) 3.53 replacement component: Any replaceable, preformed, or prepackaged component containing medium (media). [Add to Std 330.] 3.54 secondary maximum contaminant level (SMCL): The maximum permissible level of a contaminant or substance in drinking water as established in the National Secondary Drinking Water Regulations. 3.55 shelf life: The length of time a material, substance or product can be stored under specified environmental conditions and continue to meet all applicable specification requirements and/or perform its intended function. 3.56 system: A complete water treatment device, including all components needed to connect it to a potable water supply. 3.57 total dissolved solids (TDS): The remaining solids from a filtrate evaporated to dryness and dried to a constant weight at 180 °C (356 °F) after passing through a glass fiber filter. 3.58 treatment train: A serial combination of individual or integral water treatment technologies in a system each of which is capable of reducing one or more contaminants from water. [Add to Std 330.] 3.59 turbidity: A condition caused by the presence of suspended matter, or colloidal matter, or both, which results in the scattering and absorption of light rays. 3.60 unit void volume: Total water holding volume with the filter medium or components or both in place. 3.61 unit volume: Total water holding volume without the filter medium, or components, or both, in place. 3.62 watertight: A condition existing in equipment and material of such precision of construction and fit as to be impermeable to water. 3.63 weepage: The formation of bubbles or droplets of water on the outside of a fiber glass tank during the initial phase of a pressure test due to the expression of water that was trapped between the tank liner and the fiber glass wrap during the tank manufacturer’s testing. 3.64 working pressure: Feed water or inlet water pressure to a system. 3.64.1 maximum working pressure: The maximum operating pressure recommended by the manufacturer. 4 Materials 4.1 Materials in contact with drinking water Materials in contact with drinking water shall not impart levels of extractable contaminants that exceed the MCC or MDWL values specified in tables 1 and 2 when evaluated and tested in accordance with 4.2. NOTE – The concentration of active agents or additives used in the drinking water treatment process shall be evaluated in the product water as specified in 6.1. 7 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) 4.1.1 Complete formulation information on any material not certified as specifically compliant with the sections of the U.S. Code of Federal Regulations, Title 21, listed in table 3, shall be reviewed to determine whether the material presents a health effects concern in contact with drinking water and to assess the material's potential for contributing contaminants to the drinking water. NOTE – As a minimum for those materials requiring submission of formulation information, the complete chemical identity or proportion by weight (in some cases approximate weights or proportions may suffice), ingredient sources of supply, documentation regarding the health effects concern of each ingredient in the material, and documentation regarding the suitability of each ingredient for use in potable-water-contact material shall be provided. 4.1.2 The product shall be tested in accordance with 4.2.3. If the product does not impart a concentration of an extractable contaminant at a level that exceeds either the MCC or MDWL in tables 1, 2, or 4, the product shall be deemed to have met the requirements of 4. If the product does impart a concentration of an extractable contaminant at a level that exceeds the advisory concentration, but not the MCC or MDWL, the product shall be deemed to have met the requirements of 4, but the manufacturer shall be notified of the concentration of the extractable contaminant. Advisory concentrations are not used to determine acceptance to this standard. 4.1.3 Whole-system extraction testing may be waived if components, when separately tested, meet the requirements of this Standard and are assembled in a manner that does not introduce any new components, increase the surface area-to-volume ratio of previously evaluated components, or present potential concern based on cumulative factors. 4.2 Materials evaluation 4.2.1 Analytical methods All analyses shall be conducted in accordance with the applicable method(s) referenced in 2. 4.2.2 Exposure water Systems and components shall be exposed to locally available tap water that has been adjusted to contain 50 ± 5 mg/L total dissolved solids, 0.5 ± 0.05 mg/L free available chlorine, and have a pH of 6.75 ± 0.25. Exposure water used to evaluate systems or components shall be 23 ± 2 °C (73 ± 3 °F). Any existing concentrations of extraction testing parameters listed in tables 1, 2, and 4 found to be present in the exposure water shall be subtracted from the values obtained in the analysis of the extractant water. (RO/DI) with adjustment of: TDS using NaCl; pH using HCl or NaOH; and free available chlorine by adding NOTE – Adjustment of a tap water may be done by deionization (DI) or reverse osmosis followed by DI bleach (NaOCl). Tap water already containing free available chlorine may be diluted with DI or RO/DI water and adjusted as described. 4.2.3 Exposure 4.2.3.1 The system or component(s) of a system shall be installed, flushed, and conditioned in accordance with the manufacturer's instructions using the exposure water specified in 4.2.2 at an initial inlet static pressure of 340 kPa (50 psig). Pour through systems designed for open discharge or gravity flow are not exposed under pressure. These units shall be flushed and conditioned in accordance with the manufacturer's instructions using the exposure water specified in 4.2.2. 4.2.3.2 The system or component(s) shall be refilled with exposure water specified in 4.2.2 and maintained for 24 h at a temperature of 23 ± 2 °C (73 ± 3 °F). A 2-L water sample shall then be 8 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) collected in accordance with 4.2.3.3. The system or component(s) shall be flushed according to the manufacturer’s instructions, refilled, and maintained for another 24 h at a temperature of 23 ± 2 °C (73 ± 3°F). A second 2-L water sample shall be collected in accordance with 4.2.3.3. The system or component(s) shall again be flushed according to the manufacturer’s instructions, refilled, and maintained for a third period of 24 h at a temperature of 23 ± 2 °C (73 ± 3 °F). A third 2-L water sample shall be collected in accordance with 4.2.3.3. Pour through systems designed for open discharge or gravity flow shall be refilled with exposure water specified in 4.2.2 and maintained for 24 h at a temperature of 23 ± 2 °C (73 ± 3 °F). A 2-L water sample shall then be collected in accordance with 4.2.3.3. The system shall be emptied completely, refilled, and maintained for another 24 h at a temperature of 23 ± 2 °C (73 ± 3°F). A second 2-L water sample shall be collected in accordance with 4.2.3.3. The system shall again be emptied, refilled, and maintained for a third period of 24 h at a temperature of 23 ± 2 °C (73 ± 3 °F). A third 2-L water sample shall be collected in accordance with 4.2.3.3. 4.2.3.3 A minimum sample volume of 2 L shall be collected at each sample point. If the water holding volume of the product is greater than 2 L, the entire volume shall be collected in a suitable collection vessel, and a 2-L subsample obtained from this volume. If the water holding volume of the product is less than 2 L, sufficient samples shall be exposed to provide the required 2-L volume of extractant water. A maximum of 8 products shall be exposed regardless of water holding volume of product. A minimum of 250 mL shall be collected from each product. 4.2.3.4 All samples collected shall be composited and analyzed in accordance with 4.2.1. 4.2.3.5 Systems with adsorptive or absorptive media shall be tested with and without the media. Testing without media shall include removal of the media from the system, and any non-media materials or ingredients that cannot be disassociated from the media or materials that would be released into the effluent of the system in the absence of the physical barrier provided by the media. An example is the binder used to produce carbon blocks. Normalization or adjustment for changes in wetted surface area from the normal configuration shall be taken into account. An example is that carbon block end caps will have more wetted surface area exposed without the carbon block attached; therefore an appropriate adjustment in the end caps included in the exposure shall be made. 5 Design and construction 5.1 Working pressure 5.1.1 The pressure vessel(s) and all other components of a water treatment system that are subject to line pressure shall be designed and constructed to maintain structural integrity at a pressure of 690 kPa (100 psig) or the maximum working pressure, whichever is greater. Testing shall be conducted in accordance with 6.6. 5.1.2 Portable systems not designed for direct connection to a pressurized supply line shall be designed and constructed to maintain structure under the maximum pressure of the intended end-use. Testing shall be conducted in accordance with 6.6. 5.2 End-of-Life indication of mechanical reduction capacity or maximum expected life Mechanical filtration devices do not normally make claims for capacity or rated service cycle because of the broad variation in the quality and quantity of particulate matter found in drinking water. However due to the potential acute nature of the microbial contaminants filtered out by these devices, it is necessary to place a maximum limit on their use in the event their service flow remains at a desirable rate when used on water that contains very low particulate matter. Thus, a 9 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) finite operating capacity or and life (time of use) shall be established for the device by the manufacturer and be monitored by an End of Life Indicator (ELI), for example, a timer based calendar type device, which would stop the flow after this predetermined time or provide a visual or audible indication of the need to service the units. Systems claiming only cyst reduction shall be exempted from this requirement. Reduced flow also may be used as an ELI to determine when to service the units. Testing the ELI shall be in accordance with 5.2.3 or 6.11. 5.2.1 The system shall include an ELI to provide an automatic, effective means to warn the user when the system has reached the manufacturer’s claimed effective useful time, or life, or and capacity. The ELI shall warn the user when either the maximum time of use has expired or when the capacity has been reached, whichever occurs first. The ELI shall be an integral part of the system and shall activate within -20% to +10% of the manufacturer’s claimed effective useful time, life, or capacity (i.e., the acceptable activation range). The activation of the ELI shall be a distinct event within the acceptable activation range or transition to the warning indication shall begin and finish within the acceptable activation range. Information describing the operation of the indicating device shall be included in the installation, operation, and maintenance instructions, as well as information to the user that the device may provide less than the indicated life in terms of gallons, liters or time of use (months or weeks) depending on the particulate content of their water. Reason: The sub-task group decided to require effective life indication (ELI) for both volume capacity and time of use; to eliminate the cyst reduction claim from 244-3 and have it remain in Standard 53; added “reduced flow” as a means to determine when servicing the device is needed. The ELI shall be fully automatic in its operation with one allowed exception; the user may be required to inform the ELI that a replacement element has been installed. Examples of this include pushing a reset button, replacing batteries, or operating a switch. The user shall not have control of the operation of the ELI in any other manner including the setting of the activation range, tallying each batch, or other operation not required for the normal use of the system. NOTE ─ Examples of “effective means to warn the user” include but are not limited to the following: – termination of the discharge of treated water; or – the sounding of an alarm connected to an acceptable power source; or – a flashing light connected to an acceptable power source; or – provides the user with an obvious, readily interpretable indication of the system’s failure to perform, such as decreasing the initial clean system flow rate by at least 75% for systems making mechanical filtration claims The “effective means to warn the user” shall be an event that can be easily recognized by the user of the product without the use of tools. Reason: Added language consistent with Standard 53 in reference to performance indication devices 5.2.2 General filtration dDevices without reject or flush stream (dead-end operation, without waste or concentrate line) These devices shall be equipped with end-of-life indication according to 5.2.1. Dead-end operation devices shall have a life (time of use) or service frequency of no longer than 1 year. 10 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) NOTE - Other Uultra-filtration (UF) membranes or similar devices, with or without a reject or flush stream, shall require the same type of end-of-life indication as dead-end operation devices. shall have a life (time of use) or service frequency of no longer than 1 year. Other ultra-filtration (UF) membranes or similar devices, with a reject or flush stream and with or without a storage tank shall have a life (time of use) or service frequency of no longer than 2 years. These devices shall be equipped with end-of-life indicaiton according to 5.2.1. Testing shall be in accordance with 6.11. 5.2.3 Ion reduction dDevices with reject or flush streams (with or without storage tanks) Ion reduction devices such as reverse osmosis and nanomembrane-type devices shall incorporate TDS monitoring means as an integral part of the system to warn the user when the system is not performing its ion reduction function and shall include end-of-life indication as described in 5.2.1 to indicate a maximum life or service frequency of no longer than 1 2 years. The ion reduction performance of these devices shall be verified during the 3-week bacteria and virus reduction test according to 6.10.6.6. During sampling for bacteriological and virus analysis, additional influent and effluent samples shall be collected for TDS analysis. Reason: The sub-task group established a maximum time of use for devices – 1 year for deadend devices and 2 years for devices with reject or flush lines. Dead-end devices typically experience more fluctuating pressures across the filter barrier during on-off use than devices utilizing reject or constant flow flush streams. Also dead-end devices experience maximum pressure drop across the barrier during flow as it nears the minimum desired flow rate. 5.3 Elements Cartridges, filters, and similar replacement components shall be readily removable. 5.4 Flow control If the performance of a system is dependent on a specified flow rate, an automatic fixed flow-rate control shall be provided as an integral part of the system to prevent excessive flow. For POE systems without integral flow control the system shall be tested at the specified influent pressure without flow control. If the initial clean system flow rate exceeds the values in the following table the flow will be controlled downstream of the system by a flow control valve to the value indicated in the table. The flow control valve shall not be adjusted during the remainder of the test. Table for determining the maximum POE tested flow rate: Pipe Size Std 40 ID Std 80 ID ½” ¾” 1” 1-1/4” 0.622 0.824 1.049 1.38 0.546 0.742 0.957 1.278 Liters per Minute 1.5 M/s (5 ft/s) 3.0 M/s (10 ft/s) Std 40 Std 80 Std 40 Std 80 17.6 13.6 35.3 27.2 31.0 25.1 61.9 50.2 50.2 41.8 100.4 83.5 86.8 74.5 173.7 149.0 Gallons per Minute 1.5 M/s (5 ft/s) 3.0 M/s (10 ft/s) Std 40 Std 80 Std 40 Std 80 4.7 3.6 9.3 7.2 8.2 6.6 16.4 13.3 13.3 11.0 26.5 22.1 22.9 19.7 45.9 39.4 Reason: Actual flow rates were calculated based on velocities for each pipe size. The above table is for calculation purposes only. It will not appear in the final clean draft. The flow rates in red were selected based on using the calculated flow rates (rounded up) for Std Schedule 80 pipe and based on most plumbing codes limiting the maximum velocity to less than 10 ft/s. 11 Tracking number 244-3i1r9 ©NSF International System Inlet Nominal Pipe Size ½ in. BSP (½ in. NPT) ¾ in. BSP (¾ in. NPT) 1 in. BSP (1 in. NPT) 1 ¼ in. BSP (1 ¼ in. NPT) Issue 1 Revision 9 (November 2010) Maximum Flow Rate 15.1 Lpm (4 GPM) 26.5 Lpm (7 GPM) 41.6 Lpm (11 GPM) 75.7 Lpm (20 GPM) NOTE – The metric British Standard Pipe Thread is the closest equivalent to the American National Taper Pipe Thread. The maximum flow rate is calculated based upon a maximum pipe velocity of 1.27 m/sec (5 ft/sec). LPM = Liters per minute, GPM = US Gallons per minute Reason: Ballot request to “metricate” the table values to be consistent among DWTU standards. 5.5 Waste connections Waste connections or drain outlets, if provided, shall be designed and constructed to provide for connection to the sanitary waste system through an air gap of 2 pipe diameters or 25 mm (1 in), whichever is larger. 5.6 Product water dispensing outlets Product water dispensing outlets, if provided, shall be designed, constructed, and located so the discharge orifice is directed downward and the lower edge of the outlet shall be at an elevation not less than 51 mm (2 in) above the flood rim of the waste receptacle. 5.6.1 Drinking fountain outlets 5.6.1.1 The drinking water outlet shall be protected by a guard designed to (1) prevent a user from directly contacting the outlet while drinking from the system, and (2) prevent foreign matter from dropping vertically into the outlet. The guard shall be of such width, height, and design that the user's mouth or lips cannot readily touch the outlet. Spaces between the outlet and guard shall be readily accessible for cleaning. 5.6.1.2 The outlet and guard shall be designed to discourage hose connections or other improper uses. 5.6.1.3 The drinking fountain outlet shall be set to direct water flow at an angle from the vertical to prevent water in a jet from returning to the outlet. The flow from the outlet shall not touch the guard. 5.6.1.4 The lower edge of the drinking water outlet shall be at least 51 mm (2 in) above the flood rim of the waste receptacle. 5.7 Hazards All component parts shall be free of nonfunctional rough or sharp edges or other hazards that may cause injury to persons adjusting, servicing, or using the system. 5.8 Systems used in bottled water plants Systems shall have a redundant filtration element sealing mechanism such as 222 and 226 double o-ring seals. 5.9 Operation temperature 12 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) The complete system shall be designed to operate with an inlet water temperature no higher than 38 °C (100 °F). 6 Microbial, mechanical and structural performance 6.1 Active agents and additives Where an active agent or additive is used in the drinking water treatment process, the product water shall not contain that substance (or its degradation products) at a concentration of toxicological significance as given by the USEPA Primary Drinking Water Regulations, by the Health Canada Maximum Acceptable Concentrations, by any U.S. Federal regulatory agency, or at a concentration that exceeds constituent limits of the USEPA Secondary Drinking Water Regulations for all sample points. If the substance does not have a maximum drinking water concentration established by USEPA or Health Canada, a Total Allowable Concentration (TAC) shall be established according to the requirements of NSF/ANSI 61, annex A. The selection of the performance test used to evaluate the concentration of active agents shall be according to the requirements of 6.10.6.10. 6.2 Aesthetic effects claims Claims for taste, odor and other aesthetic effects, including bacteriostasis, shall not be verified under this standard. Such claims shall be tested for compliance with NSF/ANSI 42. 6.3 Health effects claims Claims for reduction of chemical, physical, (excluding cysts) radiological, or a separate claim for cyst reduction or other health effects contaminants shall not be verified under this standard. Such claims shall be verified under NSF/ANSI 44, 53, 58 or 62. 6.4 Microbiological reduction claims Claims may be made for the following microbiological reduction: • • bacteria, viruses and cysts (see 6.4.2.2) ; or cysts Separate claims for bacteria reduction or virus reduction shall not be allowed. 6.4.1 Bacteria and virus reduction The system shall meet all of the following requirements when tested in accordance with 6.10: • reduce a Brevundimonas diminuta (ATCC 19146) influent challenge of at least 50,000,000 (5 x 107) cfu/100 mL by at least 6 logs (99.9999%); • reduce a Raoultella terrigena (ATCC 33257) influent challenge of at least 50,000,000 (5 x 107) cfu/100 mL by at least 6 logs (99.9999%); and • reduce a fr (ATCC # 15767-B1) and MS-2 (ATCC # 15597-BI) viral surrogate influent challenge having at least 5,000,000 (5 x 106) pfu/100 mL of each surrogate by at least 4 logs (99.99%). 6.4.2 Cyst reduction 13 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) 6.4.2.1 A separate claim for cyst reduction shall not be verified under this standard. The system shall be tested using one of the following options: • • live Cryptosporidium parvum oocysts (see 6.4.2.1); or polystyrene microspheres (see 6.4.2.2) 6.4.2.1 Live Cryptosporidium parvum oocyst reduction The system shall reduce the number of live Cryptosporidium parvum oocysts from an influent challenge of at least 50,000 (5 x 104) oocysts per liter by at least 99.95% when tested in accordance with 6.10.6.9. NOTE - The live Cryptosporidium parvum oocyst reduction shall not be used when testing systems intended for use in bottled water plants or at flow rates greater than 6 GPM because of laboratory personnel safety concerns. 6.4.2.2 Polystyrene microsphere reduction The polystyrene microspheres shall have 95% of particles in the range of 3.00 ± 0.15 µm. The size variation of the polystyrene microspheres shall be confirmed by electron microscopy. The system shall reduce the number of polystyrene microspheres from an influent challenge of at least 50,000 (5 x 104) polystyrene microspheres per liter by at least 99.95% when tested in accordance with 6.10.6.9. 6.4.2.3 2 Bacteria and virus surrogate cyst reduction claim Systems that have been tested according to 6.10.6 and found to meet both the bacteria and virus reduction performance requirements as specified in 6.4.1 shall be allowed to make a cyst reduction claim without conducting a separate cyst reduction verification test. 6.5 Treatment train A system that consists of a treatment train shall be evaluated using one of the options described: 6.5.1 Any single treatment technology meeting the requirements of the appropriate standard may be tested independently in a manner equal to or more conservative than the technology’s application in the system. This shall qualify the entire system for that performance claim. 6.5.2 A treatment train may be evaluated as an entire system using all the appropriate standards for each treatment technology and meeting all requirements to qualify for the performance claim. 6.5.3 A system relying on multiple technologies to achieve a required performance claim shall have each technology evaluated under the appropriate standard using the multiple technology challenge. The resultant reductions achieved by each treatment technology when added together shall meet or exceed the minimum requirements for that performance claim. Note – Multiple technology challenge is the minimum average influent challenge concentration for an individual treatment technology within a treatment train as determined by the maximum effluent concentration of the prior treatment technology during evaluation. 6.6 Structural integrity 14 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) The purpose for testing structural integrity performance is to evaluate the materials, design, and fabrication quality of the complete water treatment system. 6.6.1 Acceptance Each test of structural integrity (cyclic pressure, hydrostatic pressure, and burst pressure) shall be performed on a separate system. If the complete water treatment system is tested, a separate test of the system pressure vessel is not required. Complete systems, pressure vessels, and components shall be tested for structural integrity in accordance with 6.6.2 at the pressures specified in table 5. When more than one pressure is specified in table 5, testing shall be done at the higher pressure. Complete systems, pressure vessels, and components shall be water tight when tested for structural integrity under 6.6.2. NOTE – Weepage shall be considered acceptable at the beginning of a test, but weepage shall not begin in the middle of a test. 6.6.2 Structural integrity test methods 6.6.2.1 Apparatus An enclosure shall be provided for each system tested to prevent injury to personnel or property damage if the system fails. An apparatus that may be used for the cyclic and hydrostatic test is shown schematically in Figure 1. Pressure measuring instruments shall have a precision and accuracy of 2% at the point of measurement. 6.6.2.2 Hydrostatic pressure test – complete systems Systems designed to operate only at atmospheric pressure shall be exempt from the hydrostatic pressure test but shall be watertight in normal use. Components downstream of the system on/off valve that are not subject to pressure under the off mode, and that either contains no media subject to plugging or is not designed to contain media, shall be exempt from the hydrostatic pressure test but shall be watertight in normal use. Components that are downstream of the system on/off valve but upstream of media subject to clogging shall meet the requirements of this section. The following procedure shall be used for the hydrostatic pressure testing of other complete systems: a) A water temperature of 13 to 24 °C (55 to 75 °F) shall be used. The test water shall be adjusted to a temperature at which condensation will not form on the surface of the test unit. b) Connect the inlet of the test system to the apparatus shown in Figure 1. The system shall be in conformance with its normal state of use, with the option of plugging drain lines. c) Fill the test system with water. Flush to purge air from the system. d) Raise the hydrostatic pressure at a constant rate so that the test pressure specified in table 5 is reached within 5 min. The rate of pressure increase shall not be more than 690 kPa (100 psig) per second. e) Maintain the test pressure for 15 min. The system shall be inspected periodically through the end of the test period to check if the system is watertight. 6.6.2.3 Hydrostatic pressure test – metallic pressure vessels 15 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) The permanent increase in the circumference of the pressure vessel shall not be more than 0.2% of the original circumference when the vessel is tested in accordance with the procedures below. The circumference shall be measured at the midpoint of the sidewall of the vessel and at 30 cm (12 in) intervals. The top or bottom head deflection of the pressure vessel shall not exhibit a permanent deflection exceeding 0.5% of the vessel diameter. The test rig for metal tanks shall allow the installation of the instrumentation required to measure the change in tank circumference and the deflection of the top and bottom heads. This may require elevating the tank. Distance measuring instruments or methods shall be accurate to 0.0025 cm (0.001 in). The following procedure shall be used for the hydrostatic pressure testing of metallic pressure vessels: a) Install the test unit on the elevated rack or stand. Prepare and fill the test unit as specified in 6.6.2.2, steps a), b), and c). b) An appropriate measuring device, such as an extensometer or dial micrometer, shall be installed vertically against the tank bottom head and the tank top head, top-mounted control valve, or other component solidly mounted to the tank top. c) An appropriate measuring device, such as an extensometer or periphery tape, shall be installed around the tank perpendicular to its axis and 15 cm (6 in) above its bottom. Additional measurement devices shall be placed, vertically spaced not more than 30 cm (12 in) apart, up the side sheet of the tank. The uppermost device shall be within 30 cm (12 in) of the tank top head. If the tank length is less than 61 cm (24 in), a measuring device should be placed at the midsection. When using extensometers, the flexible wire shall be wrapped once around the tank perpendicular to its axis and 15 cm (6 in) above its bottom. One end of the wire shall be fastened to a solid post at the same elevation. The other end shall be fastened to a second post at the same elevation by means of a spring so as to maintain the wire taut. The blocks shall be fastened to each end of the wire, adjacent to the tank, such that they are spaced 15 to 20 cm (6 to 8 in) apart. For larger tanks, the spacing shall be permitted to be increased to avoid contact between the blocks and the tank. Blocks shall be attached to each wire wrap as previously specified. d) Take initial readings from the measurement devices before pressurizing the test unit. When using extensometers, measure the distance between the blocks on each wire with a micrometer caliper. e) Pressurize the test unit as specified in 6.6.2.2, steps d) and e). f) Take final readings from the extensometers or measurement devices with no pressure on the unit. g) The difference between the readings of each measurement device is the measure of permanent deformation of either the tank bottom or top head. The difference in measurement around the tank is the increase in tank circumference. 6.6.2.4 Burst test – nonmetallic pressure vessels The following procedure shall be used for the burst testing of nonmetallic pressure vessels: a) A water temperature of 13 to 24 °C (55 to 75 °F) shall be used. The test water shall be adjusted to a temperature at which condensation will not form on the surface of the test unit. b) Assemble a complete unit, as normally installed and operated. 16 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) c) Connect the pressure vessel to a water supply through a pump system with a pressure measurement device that has a method of indicating maximum pressure during a test, a check valve, a shut-off valve, and a drain valve. Threaded fittings are to be used for the system subject to the high pressure. d) Close all remaining pressure vessel openings by using threaded fittings, where possible. Fill the entire system with water and flush to purge air from the unit. e) Raise the hydrostatic pressure until the burst pressure specified in table 5 is reached or the vessel fails at a lower pressure. The rate of pressure increase shall be no more than 690 kPa (100 psig) per second and shall be sufficient to reach the burst pressure within 70 s of the start of the test. Maintain the desired pressure for an instant and release. 6.6.2.5 Cycle test The following procedure shall be used for the cyclic testing: a) A water temperature of 20 ± 3 °C (68 ± 5 °F) shall be used throughout the test. The test water shall be adjusted to a temperature at which condensation will not form on the surface of the test unit. b) Connect inlet of the test system to the test apparatus as shown in figure 1. The system shall be in conformance with its normal state of use, with the option of plugging drain lines. c) Fill the test system with water. Flush to purge air from the system. d) Set the counter to zero, or record its initial reading, and initiate pressure cycling. The pressure rise shall be ≥ 1 s and the pressure in the test unit shall return to <14 kPa (2 psig) before the initiation of another cycle. e) The pressure shall be cycled as specified in table 5. The system shall be inspected periodically through the end of the test period to check if the system is watertight. 6.7 Rated pressure drop In-line point-of-entry systems without built-in flow control shall have no more than 105 kPa (15 psig) initial pressure drop at the rated service flow with an inlet pressure of 210 kPa (30 psig) and a water temperature of 20 ± 3 °C (68 ± 5 °F). If the system has a built-in flow control or outlet, it shall comply with 6.8. 6.8 Minimum service flow The minimum initial clean-system flow rates specified in table 6 shall be attainable by the system at an inlet pressure of 210 kPa (30 psig) and a water temperature of 20 ± 3 °C (68 ± 5 °F), with a fully open outlet. 6.9 Rated service flow For systems connected to a pressurized line, the rated service flow shall be equal to or less than the minimum initial clean-system flow rate obtained during contaminant reduction testing at an inlet pressure of 410 kPa (60 psig) and a water temperature of 20 ± 3 °C (68 ± 5 °F). For systems with an internal pump, the rated service flow rate shall be equal to or less than the minimum initial clean-system flow rate obtained during contaminant reduction testing. For manual fill or pour through systems, the rated service flow rate shall be equal to or less than the minimum initial clean-system flow rate obtained during contaminant reduction testing. 17 Tracking number 244-3i1r9 ©NSF International 6.10 Issue 1 Revision 9 (November 2010) Microbiological reduction test methods 6.10.1 Apparatus A test apparatus capable of providing specified flow rates and pressures shall be used. Refer to figure 2 for an example of the test apparatus. The use of extraneous plumbing or any device between the pressure measurement point and the tested device shall be minimized. The diameter of downstream equipment and plumbing (including faucets) used in testing shall be equal to or greater than the diameter at the connection to the tested device. 6.10.2 Analytical methods All chemical and physical analyses shall be conducted in accordance with the applicable methods referenced in 2. All microbiological and microsphere analyses shall be conducted in accordance with the applicable methods referenced in annex A, and B, C and D. 6.10.3 Test waters 6.10.3.1 General test water a) A water supply shall be treated by reverse osmosis and then shall be treated with deionization (RO/DI water). The RO/DI water shall have the following minimum characteristics: • • • Conductivity of ≤ 2 μS/cm at 25°C, and TOC of < 100 μg/L, and HPC ≤ 100/10 mL A storage tank shall be filled with the RO/DI water. All chemical additions shall take place after the tank is filled with the RO/DI water. Reagent grade chemicals shall be used for all additions. HPC (heterotrophic plate count) bacteria shall be analyzed and enumerated in accordance with the applicable methods in annex A. b) The day the test is to begin the RO/DI water shall be adjusted to meet the following specific characteristics either by batch addition or in-line injection: Chlorine or other disinfectant residual hardness (as CaCO3) 50 mg/L (± 10 mg/L) pH as specified (± 0.25 pH units) temperature 20°C ± 2.5°C (68°F ± 5°F) Total organic carbon (TOC) (add as Tannic acid) not detected 3.0 ± 1.0 mg/L c) The hardness shall be adjusted by adding CaCl2 and MgSO4 in a 2 Ca: 1 Mg molar ratio. Solutions of CaCl2 and MgSO4 shall be made in RO/DI water and added to the influent water. The influent water shall contain 13.4 mg/L as Ca++ (33.3 mg/L as CaCO3) and 4.1 mg/L Mg++ (16.7 mg/L as CaCO3) to give total hardness of 50 mg/L as CaCO3. 18 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) d) Additional total dissolved solids shall be added using sodium chloride, NaCl, solution made in RO/DI water. Add the NaCl solution to the influent water to give 100 mg/L as NaCl. e) Tannic acid5 shall be added to the influent water after adequate mixing of the calcium and NaCl solutions to provide 3.0 ± 1.0 mg/L total organic carbon (TOC). f) Alkalinity shall be added using a sodium bicarbonate solution. The NaHCO3 solution made with RO/DI water shall be added to the influent water to give 42 mg/L as NaHCO3. g) After adding the CaCl2, NaCl, tannic acid and NaHCO3 the influent water shall be adequately mixed. The pH shall be adjusted to the specified test water pH, if necessary, using NaOH or HCl diluted with RO/DI water. After pH adjustment (± 0.25 pH units) the influent water shall be mixed adequately and shall be stable prior to introduction to the test units 6.10.3.2 Microbial influent challenge test waters for B. diminuta Influent variations are expected but shall not fall below the concentration that is required to demonstrate the minimum required log reduction. 6.10.3.2.1 B. diminuta - The general test water in 6.10.3.1 shall be used and adjusted to pH 7.5 ± 0.25 and contain a challenge concentration of Brevundimonas diminuta ≥ 5 x 107 cfu/100 mL. 6.10.3.3 Influent challenge test water for R. terrigena 6.10.3.2.2 R. terrigena - The general test water in 6.10.3.1 shall be used and adjusted to the appropriate pH and contain a challenge concentration of R. terrigena ≥ 5 x 107 cfu/100 mL. The influent challenge water shall be analyzed for R. terrigena at the beginning of each test, at each sampling point and for batch tanks at the end of use for each tank if a sample point is not taken near the end of tank use. When prepared in a batch tank the challenge water shall not be used longer than 24 h. 6.10.3.4 Influent challenge test water for viruses 6.10.3.2.3 Viruses - The general test water in 6.10.3.1 shall be used and adjusted to the appropriate pH and contain a challenge concentration of: • • fr coliphage ≥ 5 x 106 pfu/100 mL, and MS-2 coliphage ≥ 5 x 106 pfu/100 mL The influent challenge water at the appropriate pH containing the above virus challenge shall be used in combination with the R. terrigena challenge water as specified in 6.10.6.6 and with B. diminuta as specified in 6.10.6.7. 6.10.3.5 3 Test dust loading water Test dust shall be added to the general test water specified in 6.10.3.1 for preparing the 30 NTU challenge water as specified in 6.10.3.6 for the accidental contamination test and for preparing the 10-12 NTU challenge water for the 75% flow reduction test as specified in 6.10.6.7. The test dust shall have a nominal 0 to 5-micrometer size classification and shall have 96% (by volume percent) of its particles within this range and 20% to 40% (by volume percent) of its particles greater than 2.5 micrometers6. 5 6 Source: Sigma-Aldrich Corp., CAS 1401-55-4, reagent grade, or equivalent A test dust that meets these specifications is available from Powder Technologies, Inc., PO Box 1464, 19 Tracking number 244-3i1r9 ©NSF International 6.10.3.4 Issue 1 Revision 9 (November 2010) Influent challenge test water for simulating accidental contamination The general test water in 6.10.3.1 shall be used and adjusted to have the following parameters: • • • • Total organic carbon (added as tannic acid), 10 mg/L (± 20%); Turbidity (added as test dust described in 6.10.3.5), 30 NTU (± 10%); Total dissolved solids (TDS, added as NaCl), increased to 1,500 mg/L (± 10%); and pH 9.0 ± 0.25 6.10.4 Servicing of components If clogging occurs during testing, systems with separate mechanical filtration components as pretreatment to the primary mechanical reduction filter may have the mechanical prefiltration components replaced or serviced in accordance with the manufacturer's instructions to maintain the test flow rate. NOTE – Systems with a prefiltration treatment train may be tested in accordance with 6.5. 6.10.4.1 If clogging occurs (≥ 75% reduction of initial clean system flow rate) during the 3week performance test (6.10.6.6), systems with separate mechanical filtration components (prefilters not primarily responsible for the microbiological reduction) may have the mechanical prefiltration components replaced or serviced in accordance with the manufacturer’s instructions to maintain the test flow rate. If after the prefilter components are changed and the system flow rate is still reduced by ≥ 75% from the initial clean system flow rate, see 6.10.6.8. 6.10.4.2 Filters that call for a cleaning or servicing procedure as part of the manufacturer’s instructions to maintain service flow shall be tested according to 6.10.6. 6.10.5 Conditioning the test apparatus and negative control Properly clean and sanitize the test apparatus without the systems installed using the appropriate test water in 6.10.3, while taking care to minimize bacterial contamination. Place connector tubing across the connections where the systems are to be installed in the test apparatus. After sanitizing, flush the test apparatus to less than detectable concentration of residual sanitizing agent(s). 6.10.5.1 After the test apparatus has been sanitized and rinsed begin flow and collect into a sterile container at 5-minute intervals 3 one-liter volumes (or the appropriate quantity for analysis) from each of the sampling ports. These samples shall be analyzed for K. terrigena and B. diminuta HPC bacteria in accordance with the applicable methods in annex A. The arithmetic average of the 3 samples from each port shall contain no more than 500 cfu HPC/mL. 6.10.5.2 Determine the flow rate of the test system by subjecting a system to dynamic pressures of 140 kPa (20 psig), 210 kPa (30 psig), 280 kPa (40 psig), 340 kPa (50 psig), 410 kPa (60 psig), 480 kPa (70 psig), 550 kPa (80 psig), 620 kPa (90 psig), and 690 kPa (100 psig) and to a system’s maximum working pressure ± 5% and measuring the flow rate at each pressure. The maximum flow rate observed shall be the evaluation service flow. Systems described in 5.2.3, batch systems, and systems designed for bottled water plants shall be exempted from this test. These types of systems shall be tested according to the maximum operating pressure and flow conditions specified in the manufacturer’s installation, operating and maintenance instructions. Burnsville, MN 55337 20 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) 6.10.5.2.1 The maximum flow rate for batch systems shall be determined according to the manufacturer’s recommended use pattern or by applying the manufacturer’s recommended maximum working pressure. 6.10.5.2.2 Systems designed with a removable flow restrictor or which are capable of being constructed without the designed flow restriction, shall be allowed to be performance tested with the flow restriction removed at the maximum flow rate obtained in 6.10.5.2. 6.10.5.2.3 The maximum flow rate for POE systems and systems designed for bottled water plants shall be determined according to 5.4 6.10.5.3 Install two new systems to be tested as shown in Figure 2 and condition each unit in accordance with the manufacturer’s instructions with the appropriate test water in 6.10.3. Testing of systems described in 5.2.3, or systems having pretreatment means, shall be determined by the testing agency according to 6.5, if applicable. 6.10.5.4 At the termination of conditioning in 6.10.5.3 and prior to start-up for each batch tank, the influent and effluent conditioning waters shall be analyzed for pH, alkalinity, total hardness, total dissolved solids, turbidity, residual chlorine and temperature. For non-batch, direct injection test rigs, these parameters shall be analyzed on a regular basis to establish conformance with 6.10.3.1. Other parameters may be used for purposes of future comparison and for documentation. 6.10.5.5 At the termination of the conditioning in 6.10.5.3 and prior to start-up, the effluent water from each system shall be sampled and analyzed for R. terrigena and B. diminuta. Collect one unit void volume (or the appropriate quantity for analysis) into a sterile container. 6.10.5.6 Bacteriological analysis of the samples collected in 6.10.5.1 and 6.10.5.5 shall be according to the applicable methods in annex A. 6.10.5.7 ACCEPTANCE CRITERIA FOR NEGATIVE CONTROL There shall be no detectable growth of R. terrigena or B. diminuta on the negative control plates after conditioning in 6.10.5.5. If the control plates for the test apparatus or test units are positive for R. terrigena or B. diminuta, resanitize the test apparatus or replace the test units and resample. 6.10.6 Device challenge and sampling plan 6.10.6.1 The two systems shall be tested at the maximum flow rate attainable and inlet initial dynamic pressure established in 6.10.5.2 or as otherwise specified in 5.4, 6.10.5.2.2, 6.10.6.2 or 6.10.6.3. NOTE 1 – During challenge suspension introduction to the test apparatus, the challenge suspension shall be kept on ice and stirred or sonicated if the microbe suspension is injected in-line. Prior to startup, the influent concentrations shall be verified. For batch challenge suspensions, prior to start-up, influent microbe viability shall be verified at the beginning and end of the anticipated life of a tank. NOTE 2 – Disinfection residuals, including anti-microbials and chemicals, shall be neutralized during sample collection. Chemical disinfection system’s components shall be disabled or removed prior to testing as applicable to the requirements of 6.5 and/or 6.10.6.9. 6.10.6.1.1 Systems designed for bottled water plants and POE systems shall be tested according to 6.10.6.5.5, 6.10.6.3 and 6.10.6.7, or 6.10.6.8. 21 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) 6.10.6.2 Plumbed-in systems without reservoirs and all faucet-mounted systems shall be operated on a 50% ON- 50% OFF cycle for 8 cycles (plus the number of cycles needed to get adequate size of samples) during the B. diminuta reduction challenge. Each cycle shall yield at least one bed volume of the system or one liter of water whichever is greater. Systems described in 5.2.3 shall have the tubing downstream from the primary microbiological reduction filter(s) or permeate line (tank fill line) disconnected and open to atmosphere during a continuous B. diminuta reduction challenge and an influent pressure of 550 ± 20 kPa (80 ± 3 psi). Nonplumbed pour-through-type batch treatment systems shall be tested according to the manufacturer’s recommended use pattern using the B. diminuta reduction challenge water. If there is not a recommended use pattern, the systems shall be operated on the basis of the fill volume of the influent water reservoir per batch and be challenged with a minimum of 3 batches per day with a minimum rest between batches. Analysis of samples shall be conducted according to the applicable methods in annex A. The R. terrigena and virus surrogate test shall start the next day. 6.10.6.3 For the R. terrigena test method and the virus test method, systems designed for bottled water plants, POE systems, plumbed-in systems without reservoirs and all faucet mounted systems shall be operated at an initial inlet dynamic pressure according to 6.10.6.1 on a 2 min on – and a variable off-time cycle, depending on the size of the system, for 8-16 h/d, 5 d a week followed by a 60-h (± 6 h) stagnation period. The OFF time shall be 118 min for faucet mounted units and 58 min for all other plumbed-in systems without reservoirs. For POE systems and bottled water plants it shall be 18 min. POE, plumbed-in systems and systems described in 5.2.3 shall be kept under pressure 24 h per day and tested according to the method in 6.10.6.6. Non-plumbed pour-through-type batch treatment systems shall be tested according to the operating cycle determined in 6.10.6.2. Analysis of samples shall be conducted according to the applicable methods in annex A and B. NOTE – If the manufacturer claims or estimates a volume capacity, the on-cycle time or total on/offcycles per day may be adjusted to deliver that volume over the 3-week test period, but the on-off cycle shall not exceed 10% on-90% off. For other systems having an undesignated volume capacity, the time cycles above in 6.10.6.3 shall be used to test the maximum volume of challenge water over the 3-week test period. rd After the 3 stagnation sample is collected and prior to the 75% flow reduction test, the systems shall be challenged as specified in 6.10.6.6 with the test water in 6.10.3.6 containing the R. terrigena and virus surrogates to simulate an accidental contamination event. 6.10.6.4 Following the completion of the 3-week test and the simulated accidental contamination test, the systems’ flow rate shall be reduced by 75% from the initial clean system flow rate using the test dust loading water and challenged again with B. diminuta and the virus surrogate challenge water adjusted to pH 9, according to 6.10.6.7. Systems described in 5.2.3 shall be exempted from the 75% flow rate reduction step. Analysis of samples shall be according to the applicable methods in annex A and B. Note – Systems with a storage tank but operate without a reject or waste stream shall be subject to the 75% flow reduction requirement according to 6.10.6.7. The tank fill line shall be disconnected according to the procedure in 6.10.6.5.3 and the systems challenged according to 6.10.6.7.1 and 6.10.6.7.2. 6.10.6.5 Bacteria reduction test method- B. diminuta 6.10.6.5.1 The B. diminuta bacterial challenge test water specified in 6.10.3.2 shall be used to challenge the systems at initial startup. 6.10.6.5.2 Plumbed-in systems without reservoirs and all faucet-mounted systems shall be tested according to the operating cycle in 6.10.6.2. At the beginning of the 8th on-cycle, influent and effluent samples shall be collected and analyzed for B. diminuta and HPC. Effluent samples shall be 5-unit void volumes except for POE units where 5 L samples shall be collected from them. The effluent samples shall include the first water coming from the systems after the 22 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) sampling lines are flushed. Analysis shall be conducted on 1-unit void volume (or the appropriate quantity for analysis) of the 5-unit void volume sample. The systems shall remain under pressure (if applicable) and be used for the R. terrigena and virus surrogate longer-term test the next day. 6.10.6.5.3 For plumbed-in systems with reservoir, disconnect the permeate line or tubing downstream from the primary microbiological reduction filter(s) and let run to atmosphere. Set the initial dynamic pressure to 550 ± 20 kPa (80 ± 3 psi) and start the B. diminuta challenge water. Determine the ‘to atmosphere’ permeate flow rate for later reference in 6.10.6.6.2.1 (see NOTE). After challenging continuously for 4 h, influent and effluent samples of an appropriate quantity (at least 5-unit void volume) shall be collected and analyzed for B. diminuta and HPC. Discontinue the B. diminuta challenge and reconnect the permeate line to the reservoir and continue operating the systems using the general test water in 6.10.3.1 with a repetitive complete filling and emptying of the reservoir for the remaining daily operating period. The systems shall remain under pressure (if applicable) and be used for the R. terrigena and virus surrogate longer-term test the next day. NOTE – After the B. diminuta challenge, systems with a reservoir but without a reject or waste line shall be operated by repetitive complete filling and emptying of the reservoir if the reservoir fill time exceeds 118 min. If the reservoir fill time is less than or equal to 118 min, the systems shall be operated using an on-time sufficient to empty one tank volume followed by a 118 min off-time. 6.10.6.5.4 For non-plumbed pour-through-type batch treatment systems challenge according to 6.10.6.2. After passage of at least 3 batches, representative influent and effluent (at least 5-unit void volumes) samples of an appropriate quantity shall be collected and analyzed for B. diminuta and HPC. During the challenge period, the treated water reservoir shall be removed and the sample collected in a separate sterile sample vessel to ensure the sample is not contaminated from prior challenge periods. The systems shall be used for the R. terrigena and virus surrogate longer term test the next day. NOTE – During periods of non-use, the systems shall be stored at ambient light and temperature conditions, or according to directions provided in the system’s installation, operation and maintenance instructions. 6.10.6.5.5 Bottled water plants – B. diminuta reduction test procedure 6.10.6.5.5.1 Systems designed for bottled water plants and POE systems shall be tested initially for B. diminuta reduction using the bacterial challenge test water specified in 6.10.3.2. 6.10.6.5.5.2 After the systems have been flushed and conditioned and the negative controls have been verified, the B. diminuta challenge water shall be introduced at the specified operating flow rate for a period of not less than 10 min. Influent and effluent samples shall be collected after the initial 10-min challenge. After this sampling has been completed, a pressure pulse shall be administered to the systems under test by causing a rapid interruption and resumption of flow typical of a fast-acting valve located downstream of the unit. For filtration elements that have maintenance procedures, which include re-use, backwashing, cleaning, sterilization, etc., the manufacturer’s maintenance procedures shall be followed, the filtration elements) returned to service, and the test repeated. In addition to the collection of the influent and effluent samples specified, influent and effluent samples shall be collected immediately upon resumption of flow to the systems under test. The R. terrigena and virus surrogate test method shall start the next day. 6.10.6.6 R. terrigena and virus reduction test method Following the conditioning, negative control and B. diminuta challenge, the R. terrigena bacterial challenge test water and virus challenge test water specified in 6.10.3.3 and 6.10.3.4, respectively, shall be used concurrently as specified. 23 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) Note 1- If the B. diminuta challenge starts on Monday, the next test will consist of a 4-day test the first week with R. terrigena and viruses at the specified time periods and appropriate pH, and continue 5 days per week the following weeks. Note 2- HPC shall be monitored during this test to insure HPC are not interfering with R. terrigena analysis. HPC analysis shall be conducted according to methods in Annex A. 6.10.6.6.1 For systems designed for bottled water plants, POE systems, plumbed-in systems without reservoirs and faucet mount systems 6.10.6.6.1.1 R. terrigena and virus challenge procedure a) First week (Day 2) – The combined R. terrigena bacterial challenge test water and the virus challenge test water adjusted to pH 9 specified in 6.10.3.3 and 6.10.3.4, respectively, shall be used during the designated challenge periods at the start-up of the 3-week test through the first week and 60-h (± 6 h) stagnation period (see table 6). Challenge for a minimum of 3 on-cycles or until 10-unit void volumes have passed through the system, whichever is greater. This challenge shall be repeated again after 4-8 h of operation the first day and repeated at the 4th-8th hour of operation daily in each of the 24 h periods, and again during the last 3 on-cycles before each 60-h (± 6 h) stagnation period and the first 3 oncycles after each 60-h stagnation period (see table 6). More than 3 on-cycles of challenge water may be required to meet the sample size requirement in 6.10.6.6.1.2. The general test water specified in 6.10.3.1 adjusted to the appropriate pH shall be used during the other nonchallenge on-off cycle test periods. b) Second week (Day 1) – Immediately after the R. terrigena and virus challenge and sampling following the first 60-h stagnation period at pH 9, the systems shall be challenged as specified in a) for the minimum 3 on-cycle challenge (or for a 10-unit void volume) again using both the R. terrigena and virus challenge water adjusted to pH 6. Thereafter, the systems shall be operated as described in a) challenging at the daily 4-8-h sample points using pH 6 challenge water until the end of the 2nd 60-h stagnation period. c) Third week – Immediately after the minimum 3 on-cycle challenge (or for a 10-unit void volume) following the 2nd 60-h stagnation period at pH 6, the test shall continue as specified in b) but using pH 7.5 challenge water. . d) Fourth week (Day 1), collection of 3rd 60-h stagnation – Fresh pH 7.5 challenge water as used in c) shall be made and used for challenging the systems and collecting the 3rd 60-h stagnation period samples. After collecting the stagnation samples, the systems shall be challenged for a minimum 3 on-cycle challenge (or for a 10-unit void volume) using the test water in 6.10.3.6 to simulate an accidental contamination event. Following this test, the same systems shall be subjected to the 75% flow reduction test as specified in 6.10.6.7. If one or both systems’ flow rate is reduced by ≥ 75% from the clean system flow rate after the simulated accidental contamination test is completed, flush with 4-unit bed volumes using the general test water in 6.10.3.1 and continue according to 6.10.6.7.2. NOTE – If the flow rate of either system is reduced by ≥ 75% from the initial clean system flow rate before the end of the 3-week test, see 6.10.6.8. e) For systems designed for bottled water plants and POE systems, the R. terrigena and virus challenge at pH 9 shall include a pressure pulse sample point and a sample point after maintenance procedures have been followed according to 6.10.6.5.5.2. 6.10.6.6.1.2 Sampling 24 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) Influent and effluent samples shall be collected for R. terrigena and virus surrogates analysis at the 3rd on-cycle or at least until 10-unit void volumes of challenge water have passed through the systems at the start-up of the 3-week test, and: a) after the 4th-8th hour of operation at the beginning of the 1st on-cycle in each 24 h period; b) during the last on-cycle(s) just prior to each 60 h stagnation period; and c) at the beginning of the 1st on-cycle after each 60 h stagnation period; and after the 3rd on-cycle (or at least until 10-unit void volumes of challenge water have passed through the systems) starting a new week at a different pH, and after starting the simulated accidental contamination test, as indicated in table 6. HPC analysis shall be conducted on each influent sample collected just prior to the 60-h stagnation periods and on all 60-h stagnation samples. Effluent sample size shall be at least 5-unit void volumes. Effluent samples taken in a), b) and c) shall include the water first coming from the units after the sampling line has been flushed. Analysis shall be conducted on 1-unit void volume of the 5-unit void volume sample. 6.10.6.6.2 For plumbed-in systems with reservoir (storage tank) 6.10.6.6.2.1 R. terrigena and virus challenge procedure a) First week (Day 2)- At start-up the day after the B. diminuta challenge, the initial inlet dynamic pressure shall be adjusted to 550 ± 20 kPa (80 ± 3 psi) and the systems’ tanks drained (without sampling). For systems without a waste or reject line, depressurize the systems and drain the tanks (without sampling). Adjust the inlet pressure to 550 ± 20 kPa (80 ± 3 psi) and challenge the systems with combined R. terrigena and the virus surrogate challenge water adjusted to pH 9 as specified in 6.10.3.3 and 6.10.3.4, respectively, for the initial full day’s operation. The first tank-full shall be sampled. During the day’s run, the systems shall be operated with a repetitive complete filling and emptying of the tank allowing shut off (if applicable), or operated according to the note in 6.10.6.5.3. An 8-16-h run or at least 2 tank-fillings shall be required. At the end of the day’s operation or at the end of the 2nd tank filling, the systems shall remain pressurized and emptying of the tank shall cease until the beginning of the next day’s run. This all-day challenge shall be repeated at the start-up on the first day of the 2nd and 3rd week after the tank has been emptied and sampled for the 60-h stagnation period. b) At the beginning of the next day’s run (Day 3), one tank volume shall be collected and sampled, and the systems challenged with the general test water specified in 6.10.3.1 adjusted to pH 9 (or the appropriate pH). During the day’s run, the systems shall be operated with a repetitive complete filling and emptying of the tank allowing shut off (if applicable), or operated according to the note in 6.10.6.5.3 until the tank is emptied near the end of the day’s 8-16-h run. After the first tank is emptied and before the last tank (or 2nd tank) filling of the day starts, or near the end of the day’s 8-16-h run, the systems shall be challenged with R. terrigena and virus surrogate challenge water at pH 9 (or the appropriate pH). The tank shall be allowed to fill completely using the challenge water. This last-tank or 2nd tank challenge and filling shall be repeated at the end of each day’s run and at the last-tank or 2nd tank filling period just prior to the 60-h stagnation period. After the 60-h (± 6 h) stagnation period one tank volume shall be collected and sampled for R. terrigena, virus surrogates and HPC, and the second-week test shall begin (see table 7). c) Second week- After completion of a) and b) at pH 9, adjust the pH of the R. terrigena and virus surrogate challenge water to pH 6 and repeat steps a) and b). d) Third week- After completion of c) at pH 6, adjust the pH of the R. terrigena and virus surrogate challenge water to pH 7.5 and repeat steps a) and b). e) Fourth week (Day 1), collection of 3rd 60-h stagnation sample – After the 3rd 60-h 25 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) stagnation period, the tank shall be sampled as specified in 6.10.6.6.2.2. After collecting the stagnation samples, the systems shall be challenged as in a) to simulate an accidental contamination event using the challenge water in 6.10.3.6 until the tank is filled to system shut-off (if applicable). Following this test, the same systems shall be tested as specified in 6.10.6.7. If one or both systems’ flow rate is reduced by ≥ 75% from the initial permeate flow rate after the simulated accidental contamination test is completed, flush with 4-unit bed volumes using the general test water in 6.10.3.1 and continue according to 6.11.6.7.1. NOTE – At least 3 times per week during the test, the permeate flow rate of each system shall be determined according the procedure in 6.10.6.5.3. If the permeate flow rate of either system is reduced by ≥ 75% from the initial clean system flow rate determined in 6.10.6.5.3 before the end of the 3-week test, see 6.10.6.8. If the TDS rejection of either system falls below 75%, the test shall be terminated and recorded as a failure. 6.10.6.6.2.2 Sampling Influent and effluent samples shall be collected for R. terrigena and virus surrogate analysis from the influent during each challenge period and effluent samples from the first full tank after initial start-up and each tank at the beginning of each day’s run and the first tank after the 60-h (± 6 h) stagnation periods and the full tank after the simulated accidental contamination challenge (see table 7). After flushing the sampling line, one tank volume shall be collected in a sterilized or sanitized container. A sample of appropriate volume shall be taken from the full tank volume and analyzed for R. terrigena and virus surrogates. HPC analysis shall be conducted on each influent sample collected just prior to the 60-h stagnation periods and on all 60-h stagnation samples. Representative influent and effluent samples shall also be analyzed for TDS reduction as required in 5.2.3. 6.10.6.6.3 Non-plumbed pour-through-type batch treatment systems Two systems shall be conditioned by completely filling the raw water reservoir with the general test water specified in 6.10.3.1. The challenge water shall be allowed to filter until it reaches its natural level in the raw and treated water reservoirs. The systems shall be operated up to 16 h per 24-h period followed by a minimum 8-h rest period. The systems shall be filled completely each cycle with a measured volume. Treated water shall be discarded as necessary. 6.10.6.6.3.1 R. terrigena and virus challenge procedure a) First week (Day 2) – At the start-up of the 3-week test, the systems shall be challenged with a minimum of 3 batch volumes using the combined R. terrigena and virus surrogate challenge water adjusted to pH 9 as specified in 6.10.3.3 and 6.10.3.4, respectively. This minimum 3 batch volume challenge shall be repeated again after 4-8 h of operation, and repeated daily after 4-8 h of operation in each of the 24-h periods, and again during the last 3 batch volumes of challenge before each minimum 60-h stagnation period and the first 3 batch volume challenge after each 60-h stagnation period (see table 6). More than 3 batch volumes of challenge water may be required to meet the sample size requirement in 6.10.6.6.3.2. The general test water specified in 6.10.3.1 adjusted to the appropriate pH shall be used during the other non-challenge operating periods. b) Second week – After completion of a) at pH 9, adjust the pH of the R. terrigena and virus surrogate challenge water to pH 6 and repeat a). c) Third week – After completion of b) at pH 6, adjust the pH of the R. terrigena and virus surrogate challenge water to pH 7.5 and repeat a). d) Fourth week (Day 1), collection of 3rd 60-h stagnation period – Fresh pH 7.5 challenge water as used in c) shall be made and used for challenging the systems and collecting the 3rd 26 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) 60-h stagnation period samples. After collecting the stagnation samples, the systems shall be challenged with a minimum of 3 batch volumes using the test water in 6.10.3.6 to simulate an accidental contamination event. Following this test, the same systems shall be subjected to the 75% flow reduction test as specified in 6.10.6.7. If one or both systems’ flow rate is reduced by ≥ 75% from the clean system flow rate after the simulated accidental contamination test is completed, flush with 4-unit bed volumes using the general test water in 6.10.3.1 and continue according to 6.11.6.7.2. NOTE – If the flow rate of either system is reduced by ≥ 75% from the initial clean system flow rate before the end of the 3-week test, see 6.10.6.8. Reason: Clarification that 3rd 60-h stagnation must be completed and added the simulated accidental contamination test. 6.10.6.6.3.2 Sampling Representative influent and effluent samples shall be collected for R. terrigena and virus surrogates analysis after at least 3 batch volumes of challenge water have passed through the systems at the start-up of the 3-week test, and after the 4th-8th hour of operation at the beginning of testing and in each 24 h period, and during the last challenge period just prior to each 60-h stagnation period, and at the beginning of the first challenge period after each 60-h stagnation period, and after the simulated accidental contamination test. HPC analysis shall be conducted on each influent sample collected just prior to the 60-h stagnation periods and on all 60-h stagnation samples. Effluent samples shall be collected in the system’s reservoir and shall be one batch volume. Analysis shall be conducted on a sample of appropriate volume from the singlebatch volume sample. 6.10.6.6.4 Bacteriological and virus surrogate analysis shall be conducted according to annex A and B. If the HPC counts rise above those at which R. terrigena can be reliably counted according to annex A, the systems shall be removed from the test apparatus, the test apparatus sanitized and flushed, and the systems reattached to the test apparatus and flushed with a minimum of 10-unit void volumes of low nutrient RO/DI water (≤ 2 μS/cm, < 0.1 mg/L TOC). After flushing the systems, the test shall continue. If the subsequent HPC counts interfere with the R. terrigena enumeration, the test shall be terminated. 6.10.6.7 reduction B. diminuta and virus surrogate reduction test method at 75% flow After the three-week test and the simulated accidental contamination test is completed, the same systems tested in 6.10.6.6 shall be challenged with the combined B. diminuta bacteria challenge water as specified in 6.10.3.2 and the virus surrogate challenge water at pH 9 as specified in 6.10.3.4. Systems described in 5.2.3 shall be exempted from the 75% flow reduction requirement, however shall be challenged with B. diminuta and virus surrogates at pH 9 after the 3-week test and the simulated accidental contamination test. 6.10.6.7.1 For systems tested in 6.10.6.6.1 and 6.10.6.6.3, the 10-12 NTU test dust loading water specified in 6.10.3.5 shall be used according to the applicable operating cycle in 6.10.6.2 or 6.10.6.6.3 until the flow rate is reduced by 75% from the initial clean system flow rate. Systems tested in 6.10.6.6.2 shall be challenged according to the procedure in 6.10.6.5.3 after completion of the three-week test and the simulated accidental contamination test. The systems then shall be flushed with 4-unit bed volumes using the general test water in 6.10.3.1. 6.10.6.7.2 After flushing with the general test water, the systems shall be challenged with the combined B. diminuta bacterial challenge water and virus surrogate challenge water at pH 9 according to the challenge and sampling procedures specified in 6.10.6.5. Batch systems shall be challenged with 3 batch volumes of challenge water prior to sampling. 27 Tracking number 244-3i1r9 ©NSF International 6.10.6.8 Issue 1 Revision 9 (November 2010) Premature clogging If the flow rate of one or both of the systems tested in 6.10.6.6.1, 6.10.6.6.2 or 6.10.6.6.3 is reduced by ≥ 75% from the initial clean system flow rate prior to the completion of the 3-week test, continuance of the test shall be subject to the following: a) If the ≥ 75% flow rate reduction occurs before the end of the second week of the test, the test shall be terminated and recorded as a failure. NOTE – The 2nd week test (at pH 6) shall include the 2nd 60-h stagnation test at the beginning of rd rd the 3 week. The start of the 3 week test is at the beginning of challenging and sampling using the pH 7.5 water. b) If the ≥ 75% flow rate reduction occurs during the third week, the simulated accidental contamination event test shall be conducted during the next scheduled challenge and sample point as specified in 6.10.6.6. The test shall continue as specified in 6.10.6.6 for the remainder of the week and include the 3rd 56-h stagnation period. After collection of the 3rd 60-h stagnation samples, the systems shall be tested as specified in 6.10.6.7 with no additional flow rate reduction. c) If the ≥ 75% flow rate reduction occurs during or after the simulated accidental contamination test (following the collection of the 3rd 60-h stagnation sample), the test shall continue as specified in 6.10.6.6 and 6.10.6.7 with no additional flow rate reduction. [Verification of cyst reduction claim using latex spheres or live oocysts is covered under NSF/ANSI 53] 6.10.6.9 Cyst reduction 6. 10.6.9.1 Influent challenge – cyst The system shall be tested using one of the following challenge waters. – live Cryptosporidium parvum oocyst challenge water (6.10.6.9.1.1); or – polystyrene microsphere challenge water (6.10.6.9.1.2) 6. 10.6.9.1.1 Live Cryptosporidium parvum oocyst challenge water The oocyst challenge water shall contain live Cryptosporidium parvum oocysts as specified in 6.4.2.1 added to the general test water specified in 6.10.3.1 to achieve at least 50,000 (5 x 104) oocysts per liter. 6.10.6.9.1.2 Polystyrene microsphere challenge water The polystyrene microsphere challenge water shall contain 3.00 µm polystyrene microspheres as specified in 6.4.2.2, added to the general test water specified in 6.10.3.1 to achieve at least 50,000 (5 x 104) microspheres per liter. 6. 10.6.9.2 Cycle time 6. 10.6.9.2.1 Cycle time for cyst reduction The systems shall be operated on a 50%-on / 50%- off cycle with a 20-min cycle, for 16 h per 24h period, followed by an 8-h rest under pressure. 28 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) NOTE – If the sample period occurs near the end of the 16 h of operation and the sample collection would extend beyond the 16-h period, the collection of the sample may be delayed until the start of the next 16-h period. 6.10.6.9.2.2 Cycle time for polystyrene microsphere reduction for systems used in bottled water plants The systems shall be tested for up to 16 h per 24-h period under constant flow conditions, followed by an 8-h rest under pressure, except as provided for in 6.10.6.9.6.1. 6.10.6.9.3 Method – plumbed-in systems without reservoirs 6.10.6.9.3.1 Cyst reduction Two systems shall be conditioned in accordance with the manufacturer's instructions, using the general test water specified in 6.10.3.1. The systems shall be tested at the maximum flow rate as determined according to 6.10.5.4. The pressure shall not be readjusted although the system may experience some change in dynamic pressure. The cycle time in 6.10.6.9.2.1 shall be used. 6.10.6.9.3.1.1 procedure Polystyrene microsphere and Cryptosporidium parvum oocyst challenge The polystyrene microsphere and Cryptosporidium parvum oocyst challenge procedure shall be performed as follows: a) The challenge test water, specified in 6.10.6.9.1.1 or 6.10.6.9.1.2, shall be used until the end of the 8th cycle. b) The challenge test water shall be stopped and the test dust loading water, specified in 6.10.3.5, shall be used until the flow rate is reduced by 25%. c) The test dust loading water shall be stopped and the general test water without challenge, specified in 6.10.3.1, shall be used for 2 cycles. d) The general test water shall be stopped and the challenge test water, specified in 6.10.6.9.1.1 or 6.10.6.9.1.2, shall be used for 4 cycles. e) The challenge test water shall be stopped and the test dust loading water shall be used until the flow rate is reduced by 50% from the original flow rate. Steps c) and d) shall then be repeated. f) The challenge test water shall be stopped and the test dust loading water shall be used until the flow rate is reduced by 75% from the original flow rate. Steps c) and d) shall then be repeated. 6.10.6.9.3.2 Polystyrene microsphere reduction for systems used in bottled water plants Two systems shall be conditioned in accordance with the manufacturer’s instructions, using the general test water specified in 6.10.3.1. The systems shall be tested using the polystyrene microsphere challenge water specified in 6.10.6.9.1.2 at the rated service flow specified by the manufacturer using a dynamic test manifold inlet pressure of up to 620 kPa (90 psi) and the cycle time specified in 6.10.6.9.2.2. The manufacturer’s rated service flow ± 10% shall be maintained throughout the test using a control valve located downstream of the unit. 6.10.6.9.3.2.1 Challenge water introduction for systems used in bottled water plants 29 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) The polystyrene microsphere challenge water as specified in 6.10.6.9.1.2 shall be introduced until the collection of the start-up sample is completed. The polystyrene microsphere challenge shall be stopped. The test dust loading water as specified in 6.10.3.5 shall be introduced until the 25% pressure drop point is reached. The test dust loading water shall be terminated, and general test water specified in 6.10.3.1 shall be introduced for 10 min. The polystyrene microsphere challenge water shall be introduced for 20 min. At the end of the 20-min period, a pressure pulse shall be administered to the system, which shall be collected in the effluent sample. After sampling, the polystyrene microsphere challenge shall be terminated, and the test dust loading water shall be introduced until the next sampling point where the procedure shall be repeated. 6.10.6.9.4 Method – plumbed-in systems with reservoirs The method specified in 6.10.6.9.3 shall be followed except that where the design of the system does not lend itself to the operating cycle in 6.10.6.9.3, such as an extended recovery time, the operating cycle shall be a repetitive complete filling and emptying of the reservoir. This cycle may be continued for 24 h per day. 6.10.6.9.5 Method – batch treatment systems 6.10.6.9.5.1 Cyst reduction test method Two systems shall be conditioned by completely filling the raw water reservoir with the general test water specified in 6.10.3.1. The challenge water shall be allowed to filter until it reaches its natural level in the raw and treated water reservoirs. A filling cycle shall be established based on the time required for one half of the water to filter through the initial cycle. The filling schedules shall be maintained up to 16 h per 24-h period followed by a minimum 8-h rest period. The systems shall be filled completely each cycle with a measured volume. Treated water shall be discarded as necessary. NOTE – If the sample period occurs near the end of the 16 h of operation and the sample collection would extend beyond the 16-h period, the collection of the sample may be delayed until the start of the next 16-h period. 6.10.6.9.5.2 Polystyrene microsphere and Cryptosporidium parvum oocyst challenge procedure The polystyrene microsphere and Cryptosporidium parvum oocyst challenge procedure shall be performed as follows: a) The challenge test water, specified in 6.10.6.9.1.1 or 6.10.6.9.1.2, shall be used until the end of the 8th cycle. b) The test dust loading water, specified in 6.10.3.5, shall be used until the time required to complete 1 cycle has increased by 133% of the original cycle time. c) The general test water without challenge, specified in 6.10.3.1, shall be used for 2 cycles. d) The challenge test water, specified in 6.10.6.9.1.1 or 6.10.6.9.1.2, shall be used for 4 cycles. e) The test dust loading water shall be used until the time required for 1 filling cycle has increased by 200% from the original cycle time. Steps c) and d) shall then be repeated. f) The test dust loading water shall then be used until the time required for 1 filling cycle has increased by 400% from the original cycle time. Steps c) and d) shall then be repeated. 30 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) 6.10.6.9.6 Sampling 6.10.6.9.6.1 Plumbed-in systems without reservoir and plumbed-in systems with reservoir 6.10.6.9.6.1.1 Sampling points for polystyrene microsphere and Cryptosporidium parvum oocyst challenges The influent and effluent samples shall be collected and measured at the 8th cycle, 25%, 50%, and 75% flow reduction points. Samples for the 25%, 50%, and 75% flow reduction points shall be collected at the beginning of the 4th cycle after the introduction of the challenge test water when the effluent from the previous cycle has been flushed from the sample apparatus. The samples shall be collected at the beginning of the flow to the test unit to include any particles that may be released from the sudden increase in flow to the test unit. 6.1.6.9.6.1.2 Sampling points for polystyrene microsphere challenge for systems used in bottled water plants The influent and effluent samples shall be collected and measured at the start of the test and at 25%, 50%, 75%, 100% and 150% ± 10% of the manufacturer’s recommended maximum pressure drop at the rated service flow. Immediately prior to collection of the effluent samples, a pressure pulse shall be administered to the systems under test by causing a rapid interruption and resumption of flow typical of a fast-acting valve located downstream of the unit. For filtration elements that have maintenance procedures, which include re-use, backwashing, cleaning, sterilization, etc., the manufacturer’s maintenance procedures shall be followed, the filtration elements(s) returned to service, and the test repeated. In addition to the collection of the influent and effluent samples specified, a sample of effluent shall be collected immediately upon resumption of flow to the systems under test. 6.10.6.9.6.2 Batch treatment systems 6.10.6.9.6.2.1 procedure Polystyrene microsphere and Cryptosporidium parvum oocyst sampling Representative influent and effluent samples shall be collected: – at the beginning of the “on” portion of the 8th cycle; and – at the beginning of the “on” portion of the 4th batch of challenge test water introduced when the original filling time of the system has increased by 133%, 200%, and 400%. During the challenge period, the treated water reservoir shall be removed and the sample collected in a separate sterile sample vessel to ensure the sample is not contaminated from prior challenge periods. 6.10.6.10 Sampling for active agents Sampling for an active agent or additive shall be performed using the performance test procedure that is likely to result in the highest potential extraction of the active agent or additive. Determination of the appropriate test procedure shall consider the following: – the chemical composition of the challenge water used in the performance test; and – the duration of rest periods prior to the specified sampling points in the performance test; and – the type or composition of the active or functional media; and 31 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) – system capacity or expected life; and – if the system is constructed with separate removable components or is a singular integral unit utilizing multiple technologies, testing according to 6.5 may be appropriate NOTE – The performance test used to evaluate extraction of an active agent or additive may be a test other than that performed to verify other performance claim(s) made by the manufacturer. Some examples are provided in the following table: Type of active agent copper/zinc media silver Recommended test protocol for active agent evaluation chlorine reduction per NSF/ ANSI 42 or 3-week test 3-week test Collection of product water samples for the analysis of active agents or their degradation products, employed in the treatment of drinking water, shall be in accordance with the sampling schedule(s) for the verification of specific reduction claims or as otherwise specified in this Standard or other appropriate NSF/ANSI DWTU Standards. At least one sample shall be collected immediately after a rest period of at least 8-h duration. 6.10.7 ACCEPTANCE CRITERIA 6.10.7.1 Bacteria and virus reduction claims To qualify as a supplemental microbiological water treatment device for bacteria and virus reduction, two production systems of a type shall meet or exceed all the reduction requirements defined below. 6.10.7.1.1 B. diminuta reduction tested in accordance with 6.10.6.5 and 6.10.6.7: The total counts on the influent samples (No) and the total counts on the effluent samples (Ns) for each system shall demonstrate a reduction equal to or greater than 6 log (99.9999%). The log reduction, LR, is calculated from the equation: LR = Log10 No/Ns 6.10.7.1.2 For the longer-term test conducted in accordance with 6.10.6.6, the influent/effluent sample point pairs’ reduction requirement for R. terrigena shall meet all of the reduction requirements defined below: • The geometric mean of all the bacteria reduction sample point pairs shall be equal to or greater than 6 log reduction (99.9999%) with allowance for measurement variability of not more than 10% of the sample point pairs having less than 6 log reduction; and • neither system shall have sequential sample points demonstrating less than 6 log reduction; and • neither system shall have the sample points from the simulated accidental contamination test, the 3rd 60- h stagnation sample on the last day of the test or from the 75% flow reduction test demonstrating less than 6 log reduction. 32 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) Example- Bacteria reduction for a 3 week test conducted in accordance with 6.10.6.6.1: The long term test for R. terrigena provides 6 sample point pairs for each system the first week and 8 per week the following two weeks, plus one pair each from the 3rd 60-h stagnation, the simulated accidental contamination test, and one pair from the 75% flow reduction test for B. diminuta. If the test lasts 3 weeks the total number of sample point pairs per system is: 6 + (8 x 2) + 1 + 1 + 1 = 25 Number of sample pairs for the completed test: 25 per system x 2 systems = 50 sample pairs Maximum number of allowable sample pairs where log reduction is insufficient: 10% of 50 = 5 Exception: If the geometric mean of all sample point reductions meets or exceeds 6 log (99.9999%), and if there are ≤ 5 sample point pairs demonstrating less than 6 log reduction, the systems shall pass the 3-week test, as long as none were sequential and none were from the simulated accidental challenge test or from the last 60 h stagnation period or from the 75% flow reduction test. 6.10.7.1.3 For the virus reduction test conducted in accordance with 6.10.6.6, the influent/effluent sample point pairs’ reduction requirement for both fr and MS-2 shall meet all of the reduction requirements defined below: • The geometric mean of all the virus reduction sample point pairs shall be equal to or greater than 4 log reduction (99.99%) with allowance for measurement variability of not more than 10% of the sample point pairs having less than 4 log reduction; and • neither system shall have sequential sample points demonstrating less than 4 log reduction • neither system shall have the sample points from the simulated accidental contamination test, the 3rd 60-h stagnation sample on the last day of the test or from the 75% flow reduction test demonstrating less than 4 log reduction Example- Virus reduction for a 3-week test conducted in accordance with 6.10.6.6.1: The virus reduction test provides also for 25 sample point pairs for each system, including the 3rd 60-h stagnation, the simulated accidental contamination test and 75% flow reduction test. For each system there is also a sample point pair for each virus surrogate (fr and MS-2). Therefore, the total sample point pairs is 50 for each system. Number of sample point pairs for the completed 3-week test: 50 per system x 2 systems = 100 Maximum number of allowable sample pairs where log reduction is insufficient: 10% of 100 = 10 Exception: If the geometric mean of all sample point reductions meets or exceeds 4 log (99.99%), and if there are ≤ 10 sample point pairs demonstrating less than 4 log reduction, the systems shall pass the virus test, as long as none were sequential and none were from the simulated 33 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) accidental contamination test, or from the last 60-h stagnation period or from the 75% flow reduction test. 6.10.7.2 Cyst reduction claims To qualify for the cyst reduction claim two production systems of a type when tested in accordance with 6.10.6.9, or 6.10.6.5, 6.10.6.6 and 6.10.6.7 shall meet one of the following requirements for: • • • 6.11 live Cryptosporidium parvum oocysts reduction (see 6.4.2.1); polystyrene microspheres reduction (see 6.4.2.2); or R. terrigena, B. diminuta and virus reduction (see 6.4.1 and 6.4.2.3 2). End-of-life indicator device verification test 6.11.1 Apparatus The apparatus described in 6.11.1 shall be used. 6.11.2 Test methods End-of-life indicators (ELI’s) that are used in non-batch systems shall be evaluated by 6.11.2.1, 6.11.2.2 or 6.11.2.3. ELI’s that are utilized in a batch system shall be evaluated by 6.11.2.4. NOTE: ELI’s may be evaluated during the 3-week test using the test water in 6.10.3.1 and the challenge water in 6.10.3 if the testing requirements for the applicable test method, 6.11.2.1, 6.11.2.2 or 6.11.2.3, are met during the 3-week test. 6.11.2.1 Volume capacity Challenge flow test method a) The test systems shall be conditioned following the manufacturer’s instructions. b) The systems shall be tested with general test water as specified in 6.10.3.1. c) Two systems shall be installed on the test rig in accordance with the manufacturer’s instructions, with a calibrated flow meter in line. Faucet mounted systems shall be installed downstream of the solenoid valve. d) The flow rate shall be measured at the beginning of the test according to 6.10.5.4. The flow rate shall be monitored continuously for those systems using flow reduction as an endof-life indicator. e) The test systems shall be operated at the maximum flow rate attainable according to 6.11.5.4 and be operated according to the on-off cycle according to 6.10.6.3. f) Both devices’ ELI’s The volume required to reach the activation point shall be recorded for each ELI and each ELI shall meet the activation requirements of 5.2.1. If the warning device uses a gradual change in state, the volume where the transition began and where it completed shall be recorded. 6.11.2.2 Alternative volume capacity flow test method for high capacity systems a) For systems with a claimed capacity greater than that attainable during the 3- week test period, a flow test method according to 6.11.2.1 shall be used but with a 50%-on / 50%-off cycle, 20 min cycle length. 34 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) b) The systems shall be operated at the highest attainable flow rate using the general test water as specified in 6.10.3.1. c) The test systems shall be run up to 16 h per 24-h period until the warning device activates. d) The volume required to reach the activation point shall be recorded for each ELI and each ELI shall meet the activation requirements in 5.2.1. If the warning device uses a gradual change in state, the volume where the transition began and where it completed shall be recorded. Reason: Renamed title to reflect the actual test being conducted; added language to be consistent with NSF/ANSI Standard 53. 6.11.2.3 Test method for eEnd-of-life indication utilizing a timer (clock) mechanism a) For systems that utilize a timer mechanism to warn the user that the maximum life or time of use has expired do not claim a volume capacity but limit use based only on time of use, the manufacturer shall provide verification that the timer shall activate within –20% to +10% of the claimed maximum time of system use. The verification shall include data from testing at least 2 different timer mechanisms or shall present statistical information from other testing that demonstrates accuracy within the -20% to +10% activation range. b) Batteries shall have at least one year shelf life and, For battery powered timers, a “Use before (date – month/year)” shall be displayed on or with the battery. The battery, after beginning timer operation, shall last at least twice as long as the claimed maximum time of system use. Verification of the battery’s useful life or shelf life shall be provided by the battery manufacturer. Verification of the 200% time of use battery operating life, while connected to the timer, shall be provided by the system manufacturer for at least 2 different systems, along with information on the batteries’ “Use before (date)” at the beginning of the test. c) All battery-powered ELI’s shall provide a means to warn the user when the battery needs replacement. Examples are a flashing light and/or audible sound that can be readily noticed by the user. d) For timer mechanisms powered by other means (solar or other light source, AC/DC, etc.), the system manufacturer shall provide verification of the timer operation in accordance with the requirements in 6.11.2.3 a). Reason: Renamed title to reflect the actual test being conducted; provided more specific requirements for timer verification and power sources. 6.11.2.4 Batch test method a) The systems shall be conditioned following the manufacturer’s instructions. b) Two systems shall be operated according to the manufacturer’s instructions until the ELI is activated using general test water as specified in 6.10.3.1. c) The volume required to reach the activation point shall be recorded and shall meet the activation requirements in 5.2.1. If the warning device uses a gradual change in state, the volume where the transition began and where it completed shall be recorded. 35 Tracking number 244-3i1r9 ©NSF International 7 Issue 1 Revision 9 (November 2010) Instruction and information This standard covers bacteria, and virus and cyst reduction testing and allows a cyst reduction claim in accordance with 6.4.2.2. Systems tested under this standard shall not make claims for the reduction of R. terrigena, B. diminuta, fr coliphage and MS-2 coliphage. 7.1 Installation, operation, and maintenance instructions 7.1.1 Information setting forth complete, detailed instructions for installation, operation, and maintenance shall be provided with each system. Specific instructions shall include: – complete name, address, and telephone number of manufacturer; – model number and trade designation; – flushing and conditioning procedures; – rated service flow in L/min or L/day (gpm or gpd); – maximum working pressure in kPa (psig); – maximum operating temperature in degrees C (degrees F); – detailed installation instructions including an explanation or schematic diagram of proper connections to the plumbing system; – operation and maintenance requirements (including user responsibility, parts, and service); – sources of supply for replaceable components; – statement noting the need for the system and installation to comply with state and local laws and regulations; – statement noting that the timely maintenance of replacement elements is required to maintain proper product performance; – statement noting that the system is to be supplied only with cold water; - statement of intended use: “WARNING: This system is for use on water supplies that have been treated to public water system standards or otherwise are determined to be microbiologically safe as demonstrated by routine testing. This system has been tested to demonstrate protection against intermittent accidental microbiological contamination of otherwise safe drinking water.” This statement shall be made in the same font and size as the microbiological claim and this statement and the claim shall be simultaneously visible to the reader. - statement for non-integral, multiple component systems (treatment train): WARNING: This system may not perform as claimed unless all functioinal components are installed in their proper sequence in accordance with the installation and maintenance instructions. – statement for claims: “This system has been tested according to NSF/ANSI 244-3 for reduction/inactivation of pathogenic (disease-causing) [cysts; or bacteria, viruses and cysts]. The concentration of the indicated bacteria and viruses or cysts in water entering the system 36 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) was reduced to meet the reduction criteria, as specified in NSF/ANSI 244-3. The bacteria and virus reduction indicates verification of cyst reduction”; - systems making a separate claim for cyst reduction shall have the following statement: “This system has NOT been evaluated for the reduction of bacteria and viruses” This statement shall be made in the same font and size as the microbiological claim and this statement and the claim shall be simultaneously visible to the reader. – statement noting “Do not use with water that is microbiologically unsafe or of unknown quality. This system is not intended for use during a boil water advisory. Stop using this filter system when a boil water advisory is issued. After a boil water advisory has been discontinued and prior to reuse, sanitize and service the system as directed in the owner’s manual” – statement noting “This system not intended to control all heterotrophic plate count (HPC) bacteria.” – statement noting “For use on private wells: WARNING: Do not use on private well water until the water has been tested by a certified drinking water laboratory to determine microbial safety in accordance with regulatory standards. Before using this device on a private well, it is the responsibility of the user to have the well tested by a certified drinking water laboratory to determine microbiological safety in accordance with applicable regulatory standards. For continuous use of this device on a private well, it is the responsibility of the user to obtain frequent microbiological testing (recommended twice per year, minimum) of the well water entering the system by a certified drinking water laboratory to monitor continued compliance with the applicable regulatory standards. If the well source becomes microbiologically contaminated as indicated by testing, discontinue use of this device until sufficient well treatment and testing indicates that the water again meets the applicable regulatory standards. Following exposure of the device to microbiologically contaminated water and prior to its reuse, conduct the proper sanitization and servicing as directed in the owners manual.” This statement shall be made in the same font and size as the microbiological claim and this statement and the claim shall be simultaneously visible to the reader. 7.1.2 Where applicable and appropriate, the following information shall also be included: – model number of replacement components; – rated capacity/rated service life in liters (gallons); NOTE – Each unique model designation shall not claim a capacity or service life greater than the least reduction capacity or service life that has been verified through testing to NSF/ANSI 244-3 or other appropriate NSF/ANSI DWTU standard. – minimum working pressure in kPa (psig); – minimum operating temperature in degrees C (degrees F); – electrical requirements; – explicit instructions explaining proper sanitization and cleaning procedures during routine servicing and after a boil water advisory has been discontinued or after the system has been exposed to microbiologically unsafe water; 37 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) – explicit instructions explaining how the end-of-life indicator functions with a statement notifying the user that the device may provide less than the indicated life in terms of gallons or time of use (months or weeks) depending on the particulate content of their water; and – 7.2 diagram showing proper air gap installation to waste connections. Data plate 7.2.1 A permanent plate or label shall be affixed in a readily accessible location on each system, and shall contain, at a minimum, the following information: – model number; – manufacturer name and contact information – statement noting “Do not use with water that is microbiologically unsafe or of unknown quality.” – systems making a separate claim for cyst reduction shall have the following statement: “This system has NOT been evaluated for the reduction of bacteria and viruses. 7.2.2 Where applicable and appropriate, the following information shall also be included. If the physical size of the component does not permit affixing the following information, the information shall be prominently displayed in the literature accompanying the system and a statement shall be included on the data plate referring the user to the literature. – functional description of system (e.g., microbial inactivation); – maximum operating temperature in degrees C (degrees F); – maximum working pressure in kPa (psig); – statement of intended use: “WARNING: This system is for use on water supplies that have been treated to public water system standards or otherwise are determined to be microbiologically safe as demonstrated by routine testing. This system has been tested to demonstrate protection against intermittent accidental microbiological contamination of otherwise safe drinking water.” This statement shall be made in the same font and size as the microbiological claim and this statement and the claim shall be simultaneously visible to the reader. – statement for claims: “This system has been tested according to NSF/ANSI 244-3 for reduction/inactivation of pathogenic (disease-causing) [cysts; or bacteria, viruses and cysts]. The concentration of the indicated bacteria and viruses or cysts in water entering the system was reduced to meet the reduction criteria, as specified in NSF/ANSI 244-3. The bacteria and virus reduction indicates verification of cyst reduction”; 7.3 – model number of replacement components; – electrical requirements; – recommended frequency of replacement of critical pretreatment or accessory components. Replacement components 38 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) 7.3.1 The packaging of components, specifically for replacement purposes, shall be labeled with the following information: – model number or name of component; – model number of system(s) in which the component is to be used; and – name and address of manufacturer; – statement noting “Do not use with water that is microbiologically unsafe or of unknown quality.” – systems making a separate claim for cyst reduction shall have the following statement: “This system has NOT been evaluated for the reduction of bacteria and viruses.” – for components claiming a finite shelf life, a statement noting ‘DO NOT USE AFTER (date)’, or notification or method of informing the user that the device or component may not function as claimed after a certain time or date. 7.3.2 – Where applicable, the following information shall also be stated: rated capacity/rated service life in liters (gallons); NOTE – Each unique model designation shall not claim a capacity or service life greater than the least reduction capacity or service life that has been verified through testing to NSF/ANSI 244-3 or other appropriate NSF/ANSI DWTU standard. – operating or exchange steps; – statement noting that the system(s) conform(s) to NSF/ANSI 244-3 for the specific performance claims as verified and substantiated by test data; – functional description of system (e.g., microbial inactivation); – maximum operating temperature in degrees C (degrees F); – maximum working pressure in kPa (psig); – statement of intended use: “WARNING: This system is for use on water supplies that have been treated to public water system standards or otherwise are determined to be microbiologically safe as demonstrated by routine testing. This system has been tested to demonstrate protection against intermittent accidental microbiological contamination of otherwise safe drinking water.” This statement shall be made in the same font and size as the microbiological claim and this statement and the claim shall be simultaneously visible to the reader. – statement for claims: “This system has been tested according to NSF/ANSI 244-3 for reduction/inactivation of pathogenic (disease-causing) [cysts; or bacteria, viruses and cysts]. The concentration of the indicated bacteria and viruses or cysts in water entering the system was reduced to meet the reduction criteria, as specified in NSF/ANSI 244-3. The bacteria and virus reduction indicates verification of cyst reduction”; – model number of replacement components; – electrical requirements; 39 Tracking number 244-3i1r9 ©NSF International – Issue 1 Revision 9 (November 2010) recommended frequency of replacement of critical pretreatment or accessory components – for systems claiming a finite shelf life, a statement noting ‘DO NOT USE AFTER (date)’, or notification or method of informing the user that the device or component may not function as claimed after a certain time or date. 7.4 Performance data sheet 7.4.1 A performance data sheet shall be available to potential buyers for each system and shall include the following information: – complete name, address, and telephone number of manufacturer; – model number and trade designation; – statement of intended use: “WARNING: This system is for use on water supplies that have been treated to public water system standards or otherwise are determined to be microbiologically safe as demonstrated by routine testing. This system has been tested to demonstrate protection against intermittent accidental microbiological contamination of otherwise safe drinking water.” This statement shall be made in the same font and size as the microbiological claim and this statement and the claim shall be simultaneously visible to the reader. – statement for claims: “This system has been tested according to NSF/ANSI 244-3 for reduction/inactivation of pathogenic (disease-causing) [or cysts; or bacteria, viruses and cysts]. The concentration of the indicated bacteria and viruses or cysts in water entering the system was reduced to meet the reduction criteria, as specified in NSF/ANSI 244-3. The bacteria and virus reduction indicates verification of cyst reduction”; NOTE 1 – In addition to this statement, advertising materials may show the average percent reduction determined during verification. NOTE 2 – Average concentrations shall be the arithmetic or geometric mean (as required by the specific test method) of all reported influent challenge or product water concentrations (the detection limit value shall be used for any nondetectable concentrations). The specified percent reduction shall not be greater than the reduction calculated using the mean values of the influent challenge and the product water concentrations respectively. – systems making a separate claim for cyst reduction shall have the following statement: “This system has NOT been evaluated for the reduction of bacteria and viruses”. This statement shall be made in the same font and size as the microbiological claim and this statement and the claim shall be simultaneously visible to the reader. – Statement noting “Do not use with water that is microbiologically unsafe or of unknown quality. This system is not intended for use during a boil water advisory. Stop using this filter system when a boil water advisory is issued. After a boil water advisory has been discontinued and prior to reuse, sanitize and service the system as directed in the owner’s manual” – statement noting “For use on private wells: WARNING: Do not use on private well water until the water has been tested by a certified drinking water laboratory to determine microbial safety in accordance with regulatory standards. Before using this device on a private well, it is the responsibility of the user to have the well tested by a certified drinking water laboratory to determine microbiological safety in accordance with applicable regulatory standards. For continuous use of this device on a private well, it is the 40 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) responsibility of the user to obtain frequent microbiological testing (recommended twice per year, minimum) of the well water entering the system by a certified drinking water laboratory to monitor continued compliance with the applicable regulatory standards. If the well source becomes microbiologically contaminated as indicated by testing, discontinue use of this device until sufficient well treatment and testing indicates that the water again meets the applicable regulatory standards. Following exposure of the device to microbiologically contaminated water and prior to its reuse, conduct the proper sanitization and servicing as directed in the owners manual.” This statement shall be made in the same font and size as the microbiological claim and this statement and the claim shall be simultaneously visible to the reader. – rated service flow rate in L/min or L/day (gpm or gpd); – rated capacity/rated service life in liters (gallons); NOTE – Each unique model designation shall not claim a capacity or service life greater than the least reduction capacity or service life that has been verified through testing to ANSI/NSF 244-3 or other appropriate NSF/ANSI DWTU standard. – maximum working pressure in kPa (psig); – maximum operating temperature in degrees C (degrees F); – general installation conditions and needs; – – general operation and maintenance requirements including, but not limited to: – suggested frequency of component change or service to system; – user responsibility; and – parts and service availability. manufacturer's limited warranty; and – statement that while testing was performed under standard laboratory conditions, actual performance may vary. 7.4.2 Where applicable and appropriate, the following information shall also be included: – model number of replacement component; – electrical requirements; – pressure drop of new system in kPa (psig) at rated flow (point-of-entry systems only); – minimum working pressure in kPa (psig); – minimum operating temperature in degrees C (degrees F); and – explanation of how the end-of-life indicator functions with a statement notifying the user that the device may provide less than the indicated life in terms of gallons or time of use (months or weeks) depending on the particulate content of their water. 41 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) Table 1 – Extraction testing parameters Maximum contaminant Parameter concentration (MCC) mg/L aluminum ― antimony 0.006 arsenic 0.010 barium 2.0 beryllium 0.004 cadmium 0.005 chromium 0.1 copper 1.3 lead 0.015 manganese ― mercury 0.002 nickel ― selenium 0.05 thallium 0.002 volatile organic compounds (includes)6 total ― benzene 0.005 carbon disulfide ― carbon tetrachloride 0.005 1,2-dichloroethane 0.005 1,1-dichloroethylene 0.007 dichloromethane 0.005 1,2-dichloropropane 0.005 ethylbenzene 0.7 styrene 0.1 tetrachloroethylene 0.005 toluene 1.0 total trihalomethanes 0.080 bromodichloromethane ― bromoform ― chlorodibromomethane ― Maximum drinking water level (MDWL) mg/L Advisory concentration mg/L USEPA method(s) 0.5 ― ― ― ― ― ― ― ― 0.3 ― 0.1 ― 0.05 – 0.21 ― ― 0.052 detected3 detected3 ― 0.052, 4 0.0052, 3, 4, 5 0.051 detected3 0.052 ― detected3 200.7, 200.8 200.8, 200.9 200.8, 200.9 200.7, 200.8 200.7, 200.8, 200.9 200.8, 200.9 200.7, 200.8, 200.9 200.7, 200.8 200.8, 200.9 200.7, 200.8 200.8, 245.1 200.7, 200.8 200.8, 200.9 200.8, 200.9 ― ― 0.05 ― ― ― ― ― ― ― ― ― ― ― ― ― 0.0102 detected3, 5 ― detected3 detected5 ― detected5 detected5 0.0052 0.0052 detected5 0.0052 ― 0.0052, 5 0.0052, 5 0.0052, 5 502.2 502.2 GC/PID 502.2 502.2 502.2 502.2 502.2 502.2 502.2 502.2 502.2 502.2 502.2 502.2 502.2 42 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) Table 1 – Extraction testing parameters Parameter chloroform 1,1,1-trichloroethane 1,1,2-trichloroethane trichloroethylene vinyl chloride o-,m-,p-xylene Maximum contaminant concentration (MCC) mg/L ― 0.2 0.005 0.005 0.002 10 Maximum drinking water level (MDWL) mg/L Advisory concentration mg/L USEPA method(s) ― ― ― ― ― ― 0.0052, 5 0.0052 ― ― detected2, 5 0.0052 502.2 502.2 502.2 502.2 502.2 502.2 1 Based on the final USEPA Secondary Maximum Contaminant Level published in 56FR3573. For aluminum, the high level of 0.2 mg/L is shown to allow for products such as activated aluminum media. 2 Contaminant potentially contributed by other sources in the distribution and plumbing system. 3 Contaminant should not be intentionally present in drinking water treatment unit systems. 4 Subpopulations exist that are sensitive to exposure to this contaminant. 5 Contaminant has a Maximum Contaminant Level Goal (MCLG) of zero. 6 The referenced method includes approximately 60 chemicals. Testing for the chemicals as specifically listed is required. Others, if detected, shall be treated as having a 0.005 mg/L advisory concentration. An advisory concentration of 0.010 mg/L applies to total organic compounds. – concluded – 43 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) Table 2 – Formulation dependent extraction testing parameters Parameter Maximum contaminant concentration (MCC) mg/L ― ― 10.0 1.0 10.0 ― ― ― ― ― ― ― 0.4 Maximum drinking water level (MDWL) mg/L ― ― ― ― ― ― ― ― 0.07 0.050 3.0 1 ― ― 0.006 ― ― ― ― 0.05 ― 0.05 ― 0.05 ― 0.0102 ― 0.0102 0.0102 0.0102 0.0102 ― ― ― ― ― ― ― ― ― ― ― ― 0.05 ― ― ― ― ― ― ― ― ― ― ― 0.0012 0.0022 0.0012 detected2 detected2 detected2 detected2 detected2 detected2 detected2 detected2 detected2 tin zinc nitrate (as N) nitrite (as N) nitrate plus nitrite (as N) sulfate sulfite acrylonitrile 1,4-dioxane dimethylformamide melamine formaldehyde di-2-ethylhexyl adipate phthalate scan (includes): butyl benzyl phthalate di(2-ethylhexyl) phthalate di-n-butyl phthalate di-n-octyl phthalate diethyl phthalate dimethyl phthalate polynuclear aromatics (includes): naphthalene acenaphthylene acenaphthene fluorene phenanthrene anthracene fluoranthene pyrene benzo(a)anthracene chrysene benzo(b)fluoranthene benzo(k)fluoranthene 44 Advisory concentration mg/L 0.05 5.01 1.02, 3 0.12, 3 1.02, 3 402 0.52 0.0052 0.0052 0.030 0.3 0.12, 3 ― USEPA method(s) 200.8, 200.9 200.7, 200.8 300 300 ― 300 377.1 524.2 524.2 HPLC/UV ― 525.2 6254 550.1 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) Table 2 – Formulation dependent extraction testing parameters Parameter benzo(a)pyrene dibenzo(a,h)anthra-cene benzo(g,h,i)perylene indeno(1,2,3-cd)pyrene nitrosamines (includes): n-nitroso-di-n-butyl amine n-nitrosodimethyl-amine n-nitrosodiphenyl-amine n-nitroso-di-npropylamine acetone cyclohexanone methyl ethyl ketone methanol tetrahydrofuran Maximum contaminant concentration (MCC) mg/L 0.0002 ― ― ― Maximum drinking water level (MDWL) mg/L ― ― ― ― ― ― ― ― ― ― ― ― ― 0.00006 0.000007 0.07 0.0005 1 0.05 1 4 1 Advisory concentration mg/L USEPA method(s) ― detected2 detected2 detected2 550.1 1 Based on the final USEPA Secondary Maximum Contaminant Level published in 56 FR 3573. 2 Contaminant potentially contributed by other sources in the distribution and plumbing system. 3 Advisory concentration set at 10% of the MDWL value 4 Gas chromatography with mass spectrometry 5 Gas chromatography with detection by flame ionization or photoionization detected2 detected2 detected2 detected2 0.12, 3 0.0052, 3 0.12, 3 0.42, 3 0.12, 3 6254 GC/FID or PID5 GC/FID or PID5 502.2 GC/FID5 GC/FID or PID5 NOTE – Formulation-dependent extraction testing parameters not listed in this table shall have a corresponding MDWL established in accordance with the procedures in NSF/ANSI 61, annex A. – concluded – 45 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) Table 3 – Materials listed in U.S. Code of Federal Regulations, Title 21, not requiring formulation review Sections 172.880 178.3700 172.888 178.3720 172.878 172.884 172.886 178.3710 173.25 173.65 178.3620 Part 184 solvents Material petrolatum synthetic petroleum wax white mineral oil odorless white petroleum hydrocarbons petroleum wax Ion exchange resins – provided that the sub-section stating the composition of the resin is specified. divinyl benzene copolymer mineral oil Direct food substances affirmed as generally recognized as safe – when used in accordance with any conditions of use specified for the substance. Solvents which may be considered for solvent bonding without review are limited to acetone, methyl ethyl ketone, cyclohexanone, and tetrahydrofuran. Mixtures such as solvent cements shall be evaluated against NSF/ANSI 61 or shall be subject to formulation review. NOTE – Solvent bonding is not recommended, as solvents soak into synthetic materials and leach back out into water at relatively high levels for long periods of time. In addition, solvents can contaminate the work area and can be adsorbed by carbon in the work area. Solvents which have been reprocessed or recycled shall not be used. 46 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) Table 4 – Non-specific extraction testing parameters Advisory concentration (mg/L) USEPA method(s) phenolics 0.05 420.4 total organic carbon (TOC) 1.0 415.2 Advisory concentration (mg/L) USEPA method(s) Additional testing1 50 160.1 no follow-up recommended 351.2 analysis for specific compound(s) in material formulations, ammonium analysis, Base/Neutral scan by GC/MS2 (for non-polar compounds), LC/MS3 (for target polar compounds) Required parameter Formulation dependent parameter total dissolved solids (TDS) total kjeldahl nitrogen (TKN) 0.5 Additional testing1 analysis for specific phenolic compound(s) in material formulations, Base/Neutral/Acid scan by GC/MS2 analysis for specific compound(s) in material formulations, Base/Neutral/Acid scan by GC/MS2 (for non-polar compounds), LC/MS3 (for target polar compounds) 1 The additional testing required may include one or more of the analyses. 2 Gas chromatography with mass spectroscopy (GC/MS) 3 Liquid chromatography with mass spectroscopy (LC/MS) 47 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) Table 5 – Structural integrity testing requirements Complete systems Complete systems with pressure vessels having a diameter < 203 mm (8 in) Complete systems with pressure vessels having a diameter of > 203 mm (8 in) Complete systems designed for open discharge2 Complete portable systems pressurized by user3 Components Metallic pressure vessels having a diameter < 203 mm (8 in)4 Metallic pressure vessels having a diameter of ∃ 203 mm (8 in)4 Nonmetallic pressure vessels having a diameter < 203 mm (8 in) Nonmetallic pressure vessels having a diameter of > 203 mm (8 in) Disposable metallic pressure vessels and components Disposable nonmetallic pressure vessels and components Valves and controls5 1 Hydrostatic pressure test1 3 x maximum working pressure or 2,070 kPa (300 psig) 1.5 x maximum maximum working pressure or 1,040 kPa (150 psig) 1.5 x maximum working pressure or 1,040 kPa (150 psig) Burst pressure test1 Cyclic pressure test1 none 100,000 cycles at 0 to 1,040 kPa (0 to 150 psig) or maximum working pressure none 100,000 cycles at 0 to 1,040 kPa (0 to 150 psig) or maximum working pressure none 10,000 cycles at 0 to 345 kPa (0 to 50 psig) none none Burst pressure test Cyclic pressure test 1.5 x maximum working pressure Hydrostatic pressure test 3 x maximum working pressure or 2,070 kPa (300 psig) 1.5 x maximum working pressure or 1,040 kPa (150 psig) 3 x maximum working pressure or 2,070 kPa (300 psig) 1.5 x maximum working pressure or 1,040 kPa (150 psig) 3 x maximum working pressure or 2,070 kPa (300 psig) 3 x maximum working pressure or 2,070 kPa(300 psig) none none 4 x maximum working pressure or 2,760 kPa (400 psig) 4 x maximum working pressure or 2,760 kPa (400 psig) none 4 x maximum working pressure or 2,760 kPa (400 psig) none none 100,000 cycles at 0 to 1,040 kPa (0 to 150 psig) or maximum working pressure 100,000 cycles at 0 to 1,040 kPa (0 to 150 psig) or maximum working pressure 100,000 cycles at 0 to 1,040 kPa(0 to 150 psig) or maximum working pressure 100,000 cycles at 0 to 1,040 kPa (0 to 150 psig) or maximum working pressure 10,000 cycles at 0 to 1,040 kPa (0 to 150 psig) or maximum working pressure 10,000 cycles at 0 to 1,040 kPa (0 to 150 psig) or maximum working pressure 100,000 cycles at 0 to 1,040 kPa (0 to 150 psig) or maximum working pressure When a choice is given in the table, testing shall be done at the greater pressure. 2 Components downstream of the system on/off valve that are not subject to pressure under the off mode, and that either contain no media subject to plugging or are not designed to contain media shall be exempt from the hydrostatic pressure test, but shall be watertight in normal use. Components that are downstream of the system on/off valve but upstream of media subject to clogging shall meet the requirements of this section. 3 Portable systems designed to utilize only atmospheric pressure or gravity flow shall be exempt from the hydrostatic pressure test, but shall be watertight in normal use. 4 Metallic pressure vessels require measurement of circumference and head deflection. The pressure vessel circumference shall not exhibit a permanent increase of more than 0.2% when measured at the midsection and at 30 cm (12 in) intervals. The top and bottom head deflection of the pressure vessel shall not exhibit a permanent deflection exceeding 0.5% of the vessel diameter. 5 Subject to line pressure and tested as separate components. 48 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) Pump Counter Low level alarm Solenoid valves Close up of cyclic controllers Cycle timer Basic hydrostatic and cyclic testing Pressure gauge Pressure relief Low level alarm Sump Solenoid valve Air cushion tank Test unit Drain Figure 1 – Structural testing apparatus 49 Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) Any suitable pressure or delivery system Pressure regulator Water supply Tank fill valve Pressure gauge Mechanical filter Influent sampling point Back flow preventer Mixer Water meters Pressure gauges Test units Pump Diaphragm pressure tank Cycling solenoid A Tank Drain line Valves NOTE 1 – Faucets shall be used in testing all systems located under or over the sink. NOTE 2 – Faucet-attached systems and portable systems shall be placed after solenoid valves B and C. NOTE 3 – Solenoid valves shall be controlled by appropriate timer(s). Product water sampling points NOTE 4 – Pressure gauges shall be located directly ahead of test units. NOTE 5 – Diameter of plumbing and equipment after test units shall not be less than the diameter at the connection to the tested unit. Figure 2 - Example 50test apparatus Cycling solenoid B Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) Table 6 Bacteria and virus surrogate reduction test Systems designed for bottled water plants, POE systems, plumbed-in systems without reservoirs and faucet mount systems and Nonplumbed pour-through-type batch treatment systems Sampling Influent* Test PointDay/Cycle/Week Week 1, Day 1 B. diminuta R. terrigena, fr, MSDay 2- initial 4-8 h Day 3- 4-8 h Day 4- 4-8 h Test Water B. dim R. ter* B. diminuta bacteria challenge test water pH 7.5 - 6.10.3.2 X HPC Effluent virus B. dim X R. ter X HPC virus X R. terrigena and virus surrogate challenge water specified in 6.10.3.3 and 6.10.3.4 at pH 9 X X X X X X X X " X X X X X X X X X X X X X X X X X X Day 54-8 h Before 60-h stagnation " Week 2, Day 1 After 60-h stagnation " X R. terrigena and virus surrogate challenge water specified in 6.10.3.3 and 6.10.3.4 at pH 6 X X X X X X X X Day 2- 4-8 h Day 3- 4-8 h Day 4- 4-8 h " X X X X X X X X X X X X Day 54-8 h Before 60-h stagnation " X X X X X X X X Week 3, Day 1 After 60-h stagnation " X X X R. terrigena and virus surrogate challenge water specified in 6.10.3.3 and 6.10.3.4 at pH 7.5 X X X X X X X X “ X X X X X X X X X X X X X X X X X X X X X X X X X X X Day 1Initial 4-8h Day 1Initial 4-8h Day 2- 4-8 h Day 3- 4-8 h Day 4- 4-8 h Day 54-8 h Before 60-h stagnation Week 4, Day 1 After 60-h stagnation High TOC, turb., TDS **B. diminuta, fr, MS-2 After 3 week test and 75% flow reductionsample per 6.10.6.7 " X X R. ter & virus, 6.10.3.6, pH 9 B. diminuta and virus surrogate challenge water specified in 6.10.3.2 and 6.10.3.4 at pH 9 X X X X X X X X X X X X *NOTE- For batch challenges, each tank shall be sampled for R. terrigena as specified in 6.10.3.3. **- Upon completion of the 3-week test, the systems shall be subjected to the 75% flow reduction test as specified in 6.10.6.7. 51 X Tracking number 244-3i1r9 ©NSF International Issue 1 Revision 9 (November 2010) Table 7 Bacteria and virus surrogate reduction test Plumbed-in systems with reservoir (storage tank) Sampling Test PointDay/Cycle/Week Test Water B. dim B. diminuta bacteria challenge Week 1, Day 1 - B. water specified in 6.10.3.2 pH 7.5 diminuta- 1st 4 h, disconnect After 4h reconnect permeate line, permeate line use General Test Water, 6.10.3.1 Day 2 – drain tank – no sample Begin R. terrigena & virus R. terrigena and virus surrogate all-day challenge challenge water specified in st 1 tank sampling 6.10.3.3 and 6.10.3.4 at pH 9 nd 2 tank or at 8-16 h Day 3- 1st tank draw, start General Test Water at pH 9 Day 3- 2 tank or last tank of 8-16-h run General Test Water specified in 6.10.3.1 at pH 9 R. terrigena and virus surrogate challenge water specified in 6.10.3.3 and 6.10.3.4 at pH 9 Day 4- 1st tank draw, start General Test Water at pH 9 General Test Water specified in 6.10.3.1 at pH 9 nd Day 4- 2 tank or last tank of 8-16-h run R. terrigena and virus surrogate challenge water specified in 6.10.3.3 and 6.10.3.4 at pH 9 Day 5- 1st tank draw, start General Test Water at pH 9 General Test Water specified in 6.10.3.1 at pH 9 nd Day 5- 2 tank or last tank before 60-h stagnation period R. terrigena and virus surrogate challenge water specified in 6.10.3.3 and 6.10.3.4 at pH 9 Week 2, Day 1 - Drain tank after 60-h stagnation period Day 1- all-day challenge, st 1 tank draw after starting R. ter. & virus pH 6 Run 8-16 h “ nd Day 2- 1st tank draw, start General Test Water at pH 6 nd Day 2- 2 tank or last tank of 8-16-h run Day 3-5- repeat Day 2 At end of Day 5 start 60-h stagnation period Week 3- repeat Week 2 but use pH 7.5 test water Week 4, Day 1 After 60-h stagnation High TOC, turb., TDS, pH 9 ***B. diminuta and virus after 3 week test per 6.10.6.7 at pH 9 Effluent# Influent* R. ter* X HPC virus B. dim X X X X R. ter X X X X Gen. Test Water in 6.10.3.1, pH 6 R. ter. & virus challenge water per 6.10.3.3 & 6.10.3.4 at pH 6 R. ter. & virus challenge water per 6.10.3.3 & 6.10.3.4 at pH 7.5 “ R. ter. & virus, 6.10.3.6, pH 9 B. diminuta and virus surrogate challenge water specified in 6.10.3.2 and 6.10.3.4 at pH 9 X X X X X X X X X X X X X X X X per sampling scheme in Week 2** X X X X X X X General Test Water specified in 6.10.3.1 at pH 6 R. terrigena and virus surrogate challenge water specified in 6.10.3.3 and 6.10.3.4 at pH 6 X X X R. terrigena and virus surrogate challenge water specified in 6.10.3.3 and 6.10.3.4 at pH 6 X X X X virus X X X HPC X X X X X X X X X X X X X X X X X X per sampling scheme in Week 2** X X X X X X X X *NOTE- For batch challenges, each feed tank shall be sampled for R terrigena as specified in 6.10.3.3. **- continue weekly testing pattern with the same daily and 60-h challenge and sample points. ***Upon completion, the systems shall # be subjected to the B. diminuta and virus surrogate test as specified in 6.10.6.7. Analyze samples for TDS as required in 5.2.3. 52