NSF International has announced that NSF/ANSI Standard 61, drinking water system components – health effects, has been expanded to allow additional types of stainless steel as acceptable materials for products used in drinking water applications. NSF/ANSI Standard 61 is the American National Standard that ensures products that come into contact with drinking water do not contribute levels of contaminants that could cause adverse human health effects such as cancer, liver and kidney damage, nervous system disorders, damage to the immune system and birth defects. The NSF/ANSI Standard verifies that stainless steels are highly resistant to leaching of contaminates into portable water. Duplex stainless steel grades 2205, 2304, 2101 and 2003, have been incorporated into the standard. These are in addition to types 304, 304L, 316 and 316L, which have previously been accepted under NSF/ANSI Standard 61. To verify the acceptability of stainless steel, NSF tested randomly selected samples from stainless steel manufacturers. The samples underwent an aggressive three-week exposure period according to the requirements of NSF/ANSI Standard 61. Collected water samples were analysed for a wide range of contaminants including lead, arsenic and chromium.
