What is NSF testing?
A. Note that it is often claimed on a filter brochure: ‘meets NSF standard 58’ (or standard 53 etc). Reading it carefully, if it doesn’t say ‘TESTED and approved to meet standard 58’ then it means that the manufacturer or retailer or their other unrecognized laboratory, is claiming it meets the same standard, but is not actually tested/approved by NSF. The NSF logo (seen in our Sierra and Watermaker product pages) is not allowed to be used unless the product has been tested and approved by them. NSF is the most respected independent body of testing, for public health and safety, in the world. There are various standards of testing done by NSF (National Sanitary Foundation). Only standard 58 is the rigorous test performed on Reverse Osmosis systems, meeting strict guidelines. For example, a carbon filter system can be certified by NSF for the functions achieved by Carbon filters e.g. Standard 42 or 53. It cannot achieve same results in above test standard 58. Bear in mind too, that a un
