A new American National Standards Institute (ANSI) standard for shower filters has been announced, and the ANSI-accredited Water Quality Association Gold Seal program will provide product testing to that standard.
NSF/ANSI 177: Shower Filtration Systems - Aesthetic Effects is a consensus standard for shower filters designed to demonstrate both performance and the safety of shower filtration products. Free available chlorine, which is used to sanitize or disinfect a public or private water supply, can cause unpleasant chlorine odors in shower water and, sometimes, chlorine-related hair or skin irritations. Using the new standard, shower filtration product providers now can certify that their devices designed to reduce the amount of free available chlorine do what they claim safely.