NSF/ANSI Standard 61:Drinking Water System Components - Health Effectshas been updated to further protect the public from exposure to lead. The changes include a reduction in the standard’s total allowable concentration (TAC) of lead, from15 ug/L to 5 ug/L. The implementation date to meet the new requirements is July 1, 2012.
The changes have also been adopted by the NSF Drinking Water Additives Joint Committee. This committee has a balance of 1/3 public health regulatory members, 1/3 product manufacturer members and 1/3 product user representatives.
NSF/ANSI Standard 61NSF/ANSI Standard 61 contains criteria for testing and evaluating products that come in contact with drinking water to ensure they do not leach contaminants into the water that would be a health concern. The standard requires a full formulation disclosure of all chemical ingredients in each water contact material and testing for any chemical contaminant that could leach from each material into drinking water. This includes both metals and organic compounds.
Most U.S. states and many Canadian provinces require products used in municipal water distribution systems and building plumbing systems to comply with the requirements of NSF/ANSI Standard 61. Contaminants include those regulated by the United States Environmental Protection Agency (USEPA) and Health Canada, as well as any other non-regulated compounds that may be of concern. Products covered under NSF/ANSI Standard 61 include the following:
- Pipes and Related Products (including pipe, hose,
- Protective and Barrier Materials (including
- Joining and Sealing Materials (including gaskets, adhesives,
- Process Media (including carbon, sand, zeolite, ion exchange media);
- Mechanical Devices (including water meters, in-line valves, filters,
- Mechanical Plumbing Devices (faucets, drinking fountains, and
- Potable Water Materials (non-metallic materials)
Evaluation RequirementsNSF/ANSI Standard 61 requires all metallic products and components to be evaluated for the leaching of lead, as well as other metal contaminants. Metallic pipe, fittings, valves, and other mechanical devices are all tested with two specially formulated waters. One is pH 5 and another pH 10.
The pH 5 test water is especially aggressive for copper, chromium, nickel, and antimony. The pH 10 test water is especially aggressive for lead, arsenic, barium, beryllium, boron, cadmium, mercury, selenium, and thallium. Products are exposed to these test waters for 16 days where the device is filled with fresh test water each day. On the 17th day, water is held in the device for 16 hours. The resulting contaminant concentrations are analyzed and mathematically normalized to reflect the concentrations expected from actual product when it is installed in the field. These normalized concentrations are then compared to the pass/fail results of NSF/ANSI Standard 61, which is 15 ppb for lead.
This pass/fail criteria of 15 ppb is scheduled to be reduced to 5 ppb. In addition to reducing the standard’s TAC of lead from 15 ug/L to 5 ug/L, there will be a reduction of the single product allowable concentration (SPAC) for lead from 1.5 ug/L to 0.5 ug/L.
Faucets, drinking fountains, and endpoint devices that dispense drinking water are tested and evaluated in a different manner. NSF/ANSI Standard 61 requires that these products be tested over a 19-day time period using specially formulated pH 8 test water. Samples for lead are taken at nine sample days throughout the 19-day test. Other metal contaminants are measured on the last day of the test. A minimum of three devices must be tested for lead, and a statistical calculation is made based on the geometric mean of the lead leach concentrations, the standard deviation of the concentrations and a probability factor, which is based on the number of products tested.
A statistical Q value is derived from this calculation to represent the lead dose of the product. Currently, an endpoint device must have a Q value less than or equal to 11 ug of lead to meet the requirements of the standard. This Q statistic criterion will be reduced from 11 to 5 for all section 9 devices components, and from 11 to 3 for supply stops, flexible plumbing connectors and miscellaneous components.
ImplementationAs previously noted, the standard changes have an implementation date of July 1, 2012, in order to provide manufacturers a reasonable amount of time to re-engineer products to meet the new requirements, to have them tested, and to make them available in the marketplace. However, manufacturers and certifiers are strongly encouraged to pursue compliance with the new requirements prior to July 1, 2012. These revisions are summarized in Annex F of the current version of the standard.
California and VermontOn January 1, 2010, the California bill AB 1953 from the 2006 legislative session that became law will go into effect. This law limits the weighted average lead content of products to not be more than 0.25% for pipes and pipe fittings, plumbing fittings, and fixtures sold in California intended to dispense water for human consumption. A similar bill from Vermont, S152, which also requires that all plumbing products comply with the 0.25% lead requirement, was recently signed into law.
Last fall, a proposal was submitted to the NSF Drinking Water Additives Joint Committee that NSF/ANSI Standard 61 be amended to allow manufacturers the option of being certified to the requirements of AB 1953. The proposal was referred to the Lead Task Group, resulting in the development of Annex G, including the evaluation methodology and calculation for compliance. Currently, Annex G is undergoing the approval process and can be found on NSF’s new standard workspace.
Through the work of the Lead Task Group, the creation of a standardized method of evaluation has been introduced to the California Building Standards Commission and the Department of Toxic Substances Control to facilitate recognition of the standard and the need for harmonization of evaluation methodologies. A full understanding of the requirements of AB 1953 will be possible once a regulatory mechanism is in place.
Coatings and lead surface treatments are not taken into account when calculating the average weight lead content in the current version of Annex G. Inclusion of these technologies will likely require a substantial effort to develop methods that evaluate their durability and long-term effects.
On the horizon, two additional proposed bills in California may become law. California bill SB 1395 proposes that lead plumbing monitoring and compliance testing be performed by the California Department of Toxic Substance Control as part of the department’s ongoing program to reduce toxic substances from the environment. The department would annually select no more than 75 drinking water faucets or other drinking water plumbing fittings and fixtures for testing and evaluation.
The other California bill, SB 1334, would require that products be certified for compliance with these provisions by an independent third-party certifier, such as NSF Intl. In addition, the bill would require that certification include testing of materials in accordance with the protocols used by the California Department of Toxic Substances Control (DTSC).
There is little more than a year left before the laws in California and Vermont become mandatory. This leaves little time for manufacturers to redesign their product lines. There are concerns that the low lead brass replacement alloys (copper, selenium, antimony and bismuth) may extract other metals at a higher rate than lead, and that certain water quality conditions will influence corrosion or metal leaching. There are also concerns that the low-leaded brass materials may not perform as long as other brass materials, or there may be field performance, corrosion, installation or maintenance issues. Also, will there be an adequate supply of bismuth and selenium available for future demand, and how will the availability impact the cost?
For more information on all of the new lead requirements in plumbing products, visit the Plumbing System Components section of the NSF Web sitehere.