Backflow tester certification is earned through documented field experience, a 40-hour training course, and written and practical exams.
The best-known credential is the ASSE 5110 Backflow Prevention Assembly Tester, but the credential that counts is the one your jurisdiction accepts — an ASSE certification, a state licence such as Texas's TCEQ BPAT, or a water purveyor's own program.
This guide covers eligibility, the certifying bodies, the exams, and renewal.
What a certified backflow tester does
A certified backflow tester is the plumbing professional who field-tests backflow prevention assemblies — the testable valves that keep water from flowing backward into a building's drinking supply.
Certification is the credential behind the title: it says you have been trained on, and examined over, the assemblies the job covers.
The ASSE 5110 practical exam alone covers four assembly types, abbreviated RP, DC, PVB and SVB.
The tests follow published field-test procedures.
ASSE tests to several of them — the USC 10th Edition, ASSE, EPA, Illinois, Missouri, one-hose and TREEO procedures are on the list — and some jurisdictions require a specific one.
The tester records the readings and reports the pass or fail to the program that requires the test: the local water purveyor or code authority.
That is the credential in one paragraph.
What the work looks like day to day, who hires testers and what the role pays belong to the role itself — see our backflow tester career and pay guide for that picture.
Who can get certified: licence and experience prerequisites
There is no single national entry rule.
The gate depends on which credential your jurisdiction accepts, and the routes differ from there.
The national reference route is a certification rather than a licence.
ASSE 5110 eligibility requires at least five years of documented, related field experience, a 40-hour training course, a written exam and a hands-on practical exam — and that five-year rule is ASSE's, not a universal one.
Where the testing credential rides on the plumber licence, you start as a licensed plumber.
Louisiana's Water Supply Protection Specialist (backflow) endorsement is available to licensed journeyman or master plumbers — or licensed landscape irrigators — who complete a 40-hour tester certification.
Washington's Backflow PL30 certificate is a plumber specialty that requires a Department of Health Backflow Assembly Tester certificate.
Minnesota's backflow (RPZ) tester credential requires current ASSE 5110 certification.
Where a state issues a standalone tester licence, a plumbing licence is not the ticket.
Texas requires its TCEQ Backflow Prevention Assembly Tester (BPAT) licence of anyone who tests or repairs backflow prevention assemblies, and its entry rules read differently: a high school diploma or GED, two years of approved experience — master or journeyman plumbing work, water system operation, irrigation and fire sprinklers are among the examples TCEQ lists — and a TCEQ-approved 40-hour course, with one of the two years substitutable by 32 semester hours of college credit or 20 extra training hours.
The licence carries scope limits too: a Texas BPAT may work on fire lines only if permanently employed by an Approved Fireline Contractor.
Which credential counts is decided locally — verify before you enroll
Who certifies backflow testers
The tester certifications a program may accept come from several kinds of bodies.
ASSE is the national reference.
Its Series 5000 professional-qualification standards cover the cross-connection field: 5110 Backflow Prevention Assembly Tester, 5120 Cross-Connection Control Surveyor/Specialist, 5130 Backflow Prevention Assembly Repairer, 5140 Fire Protection System and 5150 Backflow Prevention Program Administrator.
Testing is the assembly-level field credential in that line-up.
It is also a large one: ASSE counts more than 19,000 certified backflow professionals across the U.S. and parts of Canada, trained at more than 100 ASSE-approved schools.
The USC Foundation for Cross-Connection Control and Hydraulic Research (FCCCHR) is the other national institution in the field.
It publishes the Tenth Edition of its manual — the source of the "USC 10th Edition" field-test procedure ASSE testers can be examined on — and runs a Tester Training Course that combines lectures with hands-on wet-lab exercises.
ABPA is another body whose tester certifications count: the State Plumbing Board of Louisiana says it currently accepts all testing certifications issued by ASSE or ABPA.
States and local programs certify directly, too.
Texas requires its own TCEQ BPAT licence, and state-issued backflow tester credentials were also found in Arkansas, Virginia, Wisconsin, Minnesota and Washington.
Beyond those, many jurisdictions run their own tester certification entirely — ASSE is one accepted option among them, not the only route.
The course, the written exam and the practical exam
The ASSE route's coursework is a 40-hour training course, taught at ASSE-approved schools — more than 100 of them operate across the country.
The USC FCCCHR Tester Training Course covers the field differently: lectures paired with hands-on wet-lab exercises.
Two exams follow.
ASSE 5110 candidates sit a written exam and a hands-on practical exam, and the practical covers the four assembly types: RP, DC, PVB and SVB.
State routes structure it their own way.
For the Texas BPAT, the written exam is taken at a TCEQ-approved computer-based testing centre, the practical is given by the training provider, and the application fee is $111.
One gap to be honest about: our research did not confirm what courses cost.
Course and exam fees are set by the approved schools and training providers, so ask them — and your water purveyor — for current prices before you enroll.
Registering with your water purveyor
The certificate alone rarely puts you to work.
Backflow testing exists because water suppliers must protect the public grid, and the program that requires each test — the local water purveyor or code authority — also decides who may submit results and under which credential.
Some programs keep their own tester lists.
North Dakota's State Plumbing Board publishes a list of certified backflow assembly testers, and St. Louis County issues backflow (BFD) tester certificates through its own plumbing licensing office.
Others name the credentials they accept: Minnesota's backflow (RPZ) tester credential requires current ASSE 5110 certification, and Louisiana's plumbing board accepts tester certifications issued by ASSE or ABPA.
Texas goes furthest — its BPAT licence is required of anyone who tests or repairs backflow prevention assemblies in the state.
The purveyor's program sets the calendar too.
Annual testing is a common local rule, but it is not a federal one — our research did not confirm it from a primary source, so treat your water purveyor or local code as the authority on when each assembly must be tested.
If you plan to test in a new jurisdiction, make that program your first call: ask which certification it accepts, how it wants testers registered, and how results are filed.
Recertification: keeping your certification current
ASSE certifications must be renewed every three years, and recertifying up to six months early loses no time on the cycle.
Recertification is a real exam event, not a formality: ASSE 5110 testers need at least an 8-hour class, a 50-question written exam — rising to 100 questions from January 1, 2027 — and a hands-on practical exam.
State credentials run their own clocks.
Texas BPAT licences are valid three years and need 24 hours of continuing education to renew, 8 of them hands-on practical training.
Where your credential is a purveyor or utility program, its own renewal rules govern — read them when you register.
Once the credential is current, the backflow tester jobs on HVACHires are where it goes to work.
Career information, not legal advice — certification, licensing and testing requirements are set by your state program, licensing board or local water purveyor. Confirm the current rules with the authority in your jurisdiction before you act on them.