Becoming a certified backflow tester in Louisiana
LDH: plumbers licensed by the State Plumbing Board of Louisiana with a WSPS endorsement on their license are certified to install, repair and test backflow preventers. The State Plumbing Board keeps that roster.
Getting certified in Louisiana
LDH's General Tester Information form asks for the certifying body, certificate number, issue date and expiration date, and is sent with a copy of the certificate to LDH Office of Public Health Engineering Services (form updated June 30, 2026). The LDH list shows bodies such as ASSE International.
Sources: For plumbers, the WSPS endorsement is the certification; General testers register with LDH by sending a copy of their certificate
Who may test in Louisiana
LAC 51:XII.346.B: backflow preventers may be tested by a plumber licensed by the State Plumbing Board of Louisiana who holds its water supply protection specialist (WSPS) endorsement.
LAC 51:XII.346.B: testers meeting ASSE 5110, or holding a testing certificate from a national backflow certification body approved by the state health officer, may test. LDH lists these as Approved General Testers. Licensed landscape irrigation contractors with a special WSPS endorsement may test irrigation backflow preventers.
Sources: Licensed plumbers with a water supply protection specialist endorsement may test; Testers holding a recognized national certificate may also test
Common questions
Who certifies backflow testers in Louisiana?
Licensed plumbers test with a water supply protection specialist (WSPS) endorsement from the State Plumbing Board of Louisiana; other testers hold a national certification such as ASSE 5110 and register with the Louisiana Department of Health.