***Update: This standard has been revised. The current edition is NSF/ANSI 53-2017: Drinking Water Treatment Units -Health Effects. You can read more about its changes in our post NSF/ANSI 53-2019: Drinking Water Treatment Units – Health Effects.
Of the many processes utilized throughout the delivery of clean water, the actual purification of that water is surely one of the most important activities. However, water treatment must carefully be conducted to prevent the contamination of water from the very materials that seek to deem it safe. The treatment of water for the reduction of health-related contaminants is addressed in NSF/ANSI 53-2016 – Drinking water treatment units – Health effects.
NSF/ANSI 53-2016 is purposed with establishing minimum guidelines for materials, design and construction, and performance of point-of-use and point-of-entry drinking water treatment systems that are designed to reduce specific health-related contaminants in public or private water supplies. These systems can be used to treat all or part of the water at the inlet to a residential facility or a bottled water production facility. The contaminants may be microbiological, chemical, or particulate in nature.
The NSF/ANSI 53-2016 standard addresses the materials in contact with drinking water and those in contact with the user’s mouth, as well as testing for the structural performance of the systems. In addition, the standard details testing procedures for evaluating the system’s ability to reduce an assortment of contaminants, including radon, asbestos, Cryptosporidium oocysts, and inorganic volatile chemicals. Furthermore, the standard lists numerous other contaminants in its tables. This testing is to be carried out with test water.
NSF/ANSI 53-2016 revises the 2015 version of the standard. The new edition possesses the following changes:
- Added language to state that systems be conditioned using the test water with the specified contaminant for chemical reduction claims.
- CAS numbers were added to Table 4.1 (previously Table 1) of the materials evaluation criteria.
- Sampling point instructions for squeeze bottles in Annex E were clarified.
- Tables have been changed to reflect the appropriate section in which each is located.
NSF/ANSI 53-2016 was written and published by NSF International, an ANSI-accredited standards developing organization. NSF International standards provide basic criteria to promote sanitation and protection of the public health, and, as with NSF/ANSI 53-2016, they do not include provisions for mechanical and electrical safety, as those subjects are a part of governmental requirements or are addressed by other organizations.
Furthermore, just as the health effects of drinking water treatment units are underlying considerations for the protection of public health, the health effects of other aspects of drinking water must be monitored. NSF has published several standards for the health effects (and other interests) of drinking water systems, including:
NSF/ANSI 42-2017 – Drinking water treatment units – Aesthetic effects
NSF/ANSI 60-2016 – Drinking water treatment chemicals – Health effects – with Addendum
NSF/ANSI 61-2017 – Drinking water system components – Health effects
(Please refer to our past post on Drinking Water System Components Health Effects if you’d like to learn more about this standard.)