Watts Industries manufactures a complete line of potable water piping for residential and commercial use. All Watts WaterPEX tubing is manufactured in accordance with American Society for Testing and Materials (ASTM) F-876 and F-877 to SDR-9 dimensional standards. It’s listed by the National Sanitation Foundation to NSF Standards 14 and 61 for use in potable water systems. WaterPEX is listed by NSF to be in compliance with the Uniform Plumbing Code. All WaterPEX is labeled B137.5 which indicates that it is compliant to the CSA Standards B137.5.