Q&A: North American Code Requirements for Plastic Pipes and Fittings

  • Open How do I know plastic plumbing products are safe for use?

    Most state drinking water regulations and local plumbing codes require PE and PEX tubing and fittings conveying drinking water to meet NSF/ANSI Standard 61 to ensure components will not contribute harmful levels of contaminants to drinking water. All U.S. model plumbing codes and 46 of the 50 U.S. states require PVC drinking water system components to meet the requirements of NSF/ANSI Standard 61.

  • Open What is NSF/ANSI Standard 61?

    NSF/ANSI Standard 61: Drinking Water System Components-Health Effects is the American National Standard for health effects of drinking water system components. It establishes the health effects requirements for the chemical contaminants and impurities that are indirectly imparted to drinking water from products, components and materials used in drinking water systems.

    NSF/ANSI Standard 61 is overseen by the NSF Drinking Water Additives Joint Committee comprised of representation from the regulatory community, the manufacturing industry and user groups. The American National Standards Institute accredits NSF standards development procedures to ensure a balanced committee of stakeholders develops the standards in an open process. The NSF Council of Public Health Consultants, a group of 30 representatives from academia and local, state and federal regulatory agencies, provides technical advice on and oversight of the NSF standards.

    The NSF Health Advisory Board is a standing task group that consists of toxicologists from the U.S. EPA, Health Canada, state and provincial agencies, industry and private consulting firms. This group is responsible for reviewing and approving all allowable contaminant concentrations that are published in NSF/ANSI Standard 61.

  • Open What is NSF/ANSI Standard 14?

    NSF/ANSI Standard 14: Plastic Piping System Components and Related Materials is a consensus standard that enables comprehensive assessment of plumbing system products, materials and ingredients. The assessment is for health effects, quality control, quality assurance, marking, material property requirements, long-term strength evaluation and short-term product performance evaluation to various standards such as ASME, ASTM, ASSE, etc.

    NSF/ANSI 14 is used to evaluate a product for minimum performance requirements. NSF conducts its own testing, review and facility inspections when certifying products. If the product is to be used with potable water, it is also evaluated to NSF/ANSI Standard 61 to meet the NSF/ANSI Standard 14 potable water requirements. NSF/ANSI Standard 14 addresses health and performance, NSF/ANSI Standard 61 only addresses health effect concerns.

  • Open How are plastic pipe, fittings and system components tested?

    First, we perform a formulation review of the material to determine what possible contaminants could leach out into drinking water and what type of chemical extraction testing is necessary. Our policy does not allow lead as an ingredient within plastic pipe formulations.

    We expose products to formulated exposure waters, and then analyze these exposure waters for contaminants. We use three separate formulated waters during product exposure: pH 5.0 and pH 10.0 (with 2 mg/L available chlorine for PE pipe and fittings) for extraction of metallic contaminants, and pH 8.0 for organic-based contaminants.

    PE products are tested at an ambient temperature of 73° F (23° C). PEX tubing samples containing water are heated to 140° F (60° C) for domestic hot water systems or 180° F (82° C) for commercial hot systems.

    Products are conditioned by exposure to the formulated waters (with the addition of 2 mg/L available chlorine for PE products) for 14 days, with water being changed on 10 of those days.  We then analyze the water collected from the final 16-hour exposure period for contaminants.  Any contaminants found must be below EPA or Health Canada levels for regulated contaminants.  For non-regulated contaminants found, NSF/ANSI Standard 61 sets health based pass/fail levels based on review of available toxicity data using the risk assessment procedures in annex A of the standard.

  • Open What types of analyses are performed on PEX tubing?

    Water exposed to PEX tubing and associated fitting systems is tested for the following contaminants as required by NSF/ANSI Standard 61:

    • VOCs (Volatile organic compounds)
    • Semi-volatile compounds (base neutral acid scan by gas chromatography/mass spectroscopy)
    • Phenolics
    • Regulated metals including antimony, arsenic, barium, beryllium, cadmium, chromium, copper, lead, mercury, selenium and thallium
    • Methanol
    • Tertiary butyl alcohol
    • MTBE (methyl tertiary butyl ether)
    • Any other potential contaminant identified during the formulation review

    These test methods are capable of detecting contaminants in water as low as 4 parts per billion (4 ppb) and lower, equivalent to a 0.0000004 percent concentration.

    PEX tubing and various fittings, either plastic or metal, are tested together as systems for performance and health effects in accordance with industry standards to ensure product quality and end-user safety.

    Both the product manufacturer and independent third parties conduct routine quality control and quality assurance evaluations to ensure the product meets ASTM and NSF/ANSI standards. Compliance with ASTM F 876 and F 877 as well as NSF/ANSI Standard 14 ensures the end user of safety and quality.

  • Open What types of analyses are performed on PE pipe and fittings?

    Water exposed to PE pipe or fittings is tested for the following contaminants as required by NSF/ANSI 61:

    • Volatile organic compounds (VOCs)
    • Semi-volatile compounds (base/neutral/acid target and scan by GC/MS)
    • Regulated metals including antimony, arsenic, barium, beryllium, cadmium, chromium, copper, lead, mercury, selenium and thallium
    • Any other potential contaminant identified during the formulation review
  • Open What types of analyses are performed on PVC products?

    Water exposed to PVC products is tested for volatile organic compounds (VOCs), phenolics, residual chloride monomer (RVCM), antimony, arsenic, barium, beryllium, cadmium, chromium, copper, lead, mercury, selenium, tin, thallium, phthalates (for flexible PVCs) and any other potential contaminant identified during the formulation review.

  • Open How do I know if plastic plumbing products meet this requirement?

    Plastic pipe, fittings and system components meeting the health effects requirements of NSF/ANSI Standard 61 bear either the NSF-61 mark or the NSF-pw (potable water) mark on the print string.  The NSF-pw mark indicates the product meets the health requirements of NSF/ANSI 61 as well as the performance, long-term strength and quality control requirements of NSF/ANSI Standard 14: Plastic Piping Components and Related Materials.

    If a PEX product has only an NSF-rfh mark, this indicates the product has only been evaluated for radiant floor heating applications.

    If a PVC product has only an NSF-dwv or NSF-sewer mark, the product has only been evaluated for drain, waste and vent applications or for sewer applications, respectively.

  • Open What is PEX and how is PEX different from ordinary PE?

    PEX is similar to PE that has undergone some additional physical changes. The “X” in PEX stands for crosslinked. This means that PEX has additional links between the polymer chains, which provide additional performance capabilities that ordinary PE does not have. The crosslinking gives PEX tubing high performance capabilities at high operating pressures and temperatures of 160 psi at 73° F, 100 psi at 180° F and 80 psi at 200° F (as noted for SDR 9 tubing in ASTM F876).

  • Open How long has PEX been around?

    PEX tubing was developed in the 1960s in Europe. PEX has been in use in many European countries for decades. In the 1980s, PEX tubing started being used in the United States. Since then, both market demand for and production of PEX has significantly increased in North America.

  • Open Where can I find NSF listed products?

    NSF certified products can be found in our online listings.

  • Open What ensures the product consistently meets these requirements?

    For products listed for potable water applications, NSF performs at least two unannounced audits of each production facility annually. During the audit, we verify the quality control tests being done by the manufacturer and that there are no modifications to the product formulation and processing. In addition, we collect samples for laboratory retesting of each product family on an annual basis.

  • Open Whom can I contact for questions?

    If you have questions about the testing and certification of any NSF certified product, contact our Consumer Affairs Hotline at 800.673.8010 or our Regulatory Affairs Hotline at 877.867.3435, or email info@nsf.org.

  • Open Who is NSF?

    Founded in 1944, NSF International is committed to protecting and improving human health and the environment on a global scale. NSF International is a global independent organization that provides standards development, product certification, testing, auditing, education and risk management for public health and the environment. Manufacturers, regulators and consumers alike look to NSF International for the development of public health standards and certification that help protect the world’s food, water, health and consumer products.

    In 1990, the U.S. EPA replaced its own drinking water product advisory program with NSF standards, including NSF/ANSI 61, for all materials and products that treat or come in contact with drinking water. Today, most plumbing codes require certification to NSF standards for pipes and plumbing components in commercial and residential buildings.

  • Open What credentials does NSF have?

    NSF is accredited by ANSI, the American National Standards Institute, and SCC, the Standards Council of Canada, for its testing, standards writing and certification programs. NSF has decades of experience and technical expertise in the areas of water and food safety.

  • Open What services does NSF offer to the plumbing industry?

    NSF offers conformity assessment services in the areas of public health and safety to the plumbing industry. We conduct physical performance, product and material testing, long-term strength evaluations, microbiological safety testing, chemical extraction or leaching testing, and toxicological risk assessment, as well as offer production facility inspection services.

  • Open What is the level of NSF product certification recognition?

    NSF testing and certification are recognized by every plumbing code in North America. No certification mark is more widely recognized and accepted in the plumbing industry. NSF certification is considered the benchmark for product safety and performance validation.

  • Open What types of products does NSF test and certify?

    Under NSF/ANSI Standards 14, 24, 50, and 61, and the Mechanical Plumbing Program, NSF provides the plumbing industry testing and product certification services for items such as pipes, fittings, valves, pumps, chemical feeding equipment, water heaters, sinks, showers, toilets, faucets, controllers, filters, materials and ingredients. We conduct testing, listing and certification, as well as enforcement of our trademark.

  • Open How does NSF certify products?

    We evaluate products based on end use and adherence to the requirements of standards. Our evaluations routinely include health safety assessment and performance validation of products and materials. Beyond testing, our staff members conduct assessments of the quality control and quality assurance systems employed by the production facility. We register a list of materials and suppliers to manufacturers to maintain consistency and ensure quality. We also conduct unannounced surveillance inspections at the production site to review materials of use, production process and product quality, and to obtain monitoring (re-testing) samples.

  • Open What is ASTM?

    ASTM is an independent, not-for-profit standards-writing organization in many diverse technical disciplines. ASTM is the forum for a majority of standards in the USA, especially those related to plastic materials and products testing. ASTM writes standards and conducts educational training seminars (specifications, test methods and guides). ASTM does not conduct testing, listing, certifying or enforcement of its standards.

  • Open What is ASTM F 876?

    ASTM F 876-Standard Specification for Crosslinked Polyethylene (PEX) Tubing contains over one dozen performance tests such as burst pressure, sustained pressure, environmental stress cracking, density, dimensions, workmanship, degree of crosslinking and stabilizer functionality. This performance standard is used by the industry as the benchmark for minimum short-term product performance of PEX tubing.

  • Open What is ASTM F 877?

    ASTM F 877-Standard Specification for Crosslinked Polyethylene (PEX) Plastic Hot- and Cold-Water Distribution Systems contains nine performance tests such as burst pressure, sustained pressure, density, dimensions, workmanship, thermocycling, hot and cold bent tube testing and excessive temperature. This performance standard is used by the industry as the benchmark for minimum short-term product performance of PEX tubing and distribution components, like fittings.