How do you hire a backflow tester? Sourcing, pay, screening and red flags

The seat exists because backflow prevention assemblies are not self-certifying: they get field-tested by someone who holds the governing credential — a state licence in Texas, a tester certification under the many jurisdictions that run their own programs — and tested to a procedure (the USC 10th Edition, ASSE, EPA and others are in use) that some jurisdictions prescribe.

A backflow tester runs that testing on the plumbing you install and service, documents the results, and repairs or replaces the assemblies that fail.

That makes the seat unusual in your crew: part revenue (a failed test can turn into a repair or replacement job), part compliance (the results are records your water supplier can ask about), and part liability shield for your customers' potable water.

Write the job spec as a day-one list and a we-train list.

The day-one list:

• Hands-on testing. The ASSE 5110 practical exam puts candidates on four assembly types — RP, DC, PVB and SVB — and your hire should be able to test all four. The eligibility path builds exactly this: documented field experience, a 40-hour course, then written and practical exams.
• The procedure your jurisdiction requires. ASSE tests to multiple field-test procedures — the USC 10th Edition, ASSE, EPA, Illinois, Missouri, one-hose and TREEO procedures among them — and some jurisdictions require a specific one. The hire needs to know which one governs where you work.
• Documentation habits. Ask to see a test report from their last seat — what it contained and how it reached the water supplier.
• Repairs, if the job includes them. ASSE maintains a separate repairer standard (5130) alongside the tester standard, so "test and repair" is a scope decision, not a given.

The we-train list is your operation: routes and customers, your reporting software, the water suppliers you report to and what they require, and how you price a failed test.

Then pick the level, because ASSE's backflow series is a set of five standards, not a single card: 5110 Backflow Prevention Assembly Tester, 5130 Repairer, 5120 Cross-Connection Control Surveyor, 5140 Fire Sprinkler Cross-Connection Control Tester, and 5150 Program Administrator.

Decide which of those the job actually includes before you write the ad — a test-only seat and a test-and-repair-and-survey seat are different hires, at different pay, with different credentials to verify.

Two scope add-ons worth deciding early.

First, in Texas a plumber holding the TSBPE Water Supply Protection Specialist (WSPS) endorsement may perform customer service inspection certifications for public drinking water systems under 30 TAC Chapter 290 — work that pairs naturally with testing and widens what the seat can bill.

Second, decide your lane: hire someone already credentialed, or hire a strong plumber and sponsor them through the credential.

The eligibility rules below show both doors are real — Texas, for example, counts master or journeyman plumbing work among the approved experience for its tester licence.

The job-seeker-side description of the work lives in our guide to what a backflow tester does; this page stays on the hiring decision.

The governing credential is set jurisdiction by jurisdiction, and that is the first thing to nail down before you write the ad — it takes two shapes: an industry certification or a state-issued licence (sometimes both).

The industry shape: ASSE 5110.

The ASSE 5110 Backflow Prevention Assembly Tester certification has a specific eligibility path: at least five years of documented related field experience, a 40-hour training course, a written exam, and a hands-on practical on the four assembly types.

ASSE certifications renew every three years; 5110 recertification requires at least an 8-hour class, a written exam (50 questions today, rising to 100 from January 1, 2027) and a practical exam.

Note the scope of that five-year figure: it is ASSE's own entry requirement, not a universal rule — and many jurisdictions run their own tester certification instead of or alongside it.

The state-licence shape.

State-issued backflow tester credentials exist in Texas (the TCEQ BPAT licence), Arkansas (Assembly Testing Technician), Virginia (backflow prevention device worker), Wisconsin (Cross Connection Control Assembly Tester), Minnesota (the RPZ tester needs ASSE 5110) and Washington (the PL30 plumber specialty requires a DOH Backflow Assembly Tester certificate).

Louisiana and Texas also offer a plumber endorsement route — the Water Supply Protection Specialist — with Louisiana's open to licensed journeyman or master plumbers (or licensed landscape irrigators) who complete a 40-hour tester certification, with ASSE or ABPA tester certifications accepted.

Texas shows what a state-issued seat looks like in full, because the rules are detailed and named: the TCEQ Backflow Prevention Assembly Tester (BPAT) licence is required for anyone who tests or repairs backflow prevention assemblies in Texas.

Eligibility takes a high school diploma or GED, two years of approved experience (master or journeyman plumbing work, water system operation, irrigation and fire sprinklers are the examples TCEQ lists) and a TCEQ-approved 40-hour BPAT course, with one year of the experience substitutable by 32 semester hours or 20 extra training hours.

The application fee is $111; the written exam runs at a TCEQ-approved computer-based testing centre and the practical is given by the training provider.

The licence is valid three years and renews with 24 CE hours, 8 of them hands-on.

One restriction that matters for your bids: a BPAT may work on fire lines only while permanently employed by an Approved Fireline Contractor.

In the jurisdictions our research covered without a state tester licence, the governing requirement may instead be a local tester certification program or a rule that sits with the water supplier or local code.

Our research did not confirm tester rules for every state, so treat the list above as coverage, not completeness.

Verify through the issuer, before the interview.

Ask for the credential number and check it the same way you would verify plumbing license claims — with the issuing body itself: the state agency for a state licence, ASSE for the certification — not a photocopy or a resume line.

Confirm before you post.

These rules are jurisdiction-specific and they change.

Before you write requirements into the posting, confirm with your state licensing board — and with the water suppliers you report to — exactly which credential they accept for the work you bid.

If you are still working out which credential your market requires at all, our guide to what license your hire needs walks that decision for both trades.

The pool is real and it is national: ASSE counts more than 19,000 ASSE-certified backflow professionals working across all 50 states and parts of Canada, trained at more than 100 ASSE-approved schools.

Many testers come out of the plumbing trade — a workforce BLS sizes separately: 330,570 Plumbers, Pipefitters, and Steamfitters (SOC 47-2152) were employed at plumbing, heating and air-conditioning contractors in the May 2025 OEWS release.

The eligibility rules show the connection: Texas counts master or journeyman plumbing work toward its tester licence, and ASSE 5110 asks for five years of related field experience.

So the plumbing-wide channels in our guide to how to find plumbers to hire apply here too, with one specialty lane added.

Among Plumbers, Pipefitters, and Steamfitters (SOC 47-2152) — the combined trade series backflow testing sits inside — building equipment contractors employ by far the most (340,140 jobs), but utility system construction (14,960) and local government excluding schools and hospitals (11,480) are the next-largest industry employers.

That second tier is worth a dedicated search: it is where the trade works beyond the contractor shop floor — utility-line construction and local government.

• Testers at other mechanical and plumbing contractors. The direct lane. They know the paperwork and the pace; expect to compete on pay and on who files cleaner reports.
• Cross-connection control staff at water suppliers and municipalities. Utility-side testers and surveyors bring a different vantage on the same credential. Watch the credential: confirm their certification matches what your jurisdiction requires of a private tester before you assume it transfers.
• Your own journeyman plumbers. The sponsor-from-within lane. Texas counts master or journeyman plumbing work toward its tester-licence experience requirement, and ASSE's 5110 path runs through documented field experience plus the 40-hour course and exams — so a journeyman with the hours may be a course and the exams away from the credential. Budget the course, the exams and their study time as a hiring cost, and put the milestone dates in writing.
• The training network. The USC Foundation runs a Tester Training Course built on lectures and hands-on wet-lab work, and ASSE certifies through its 100-plus approved schools — the places working testers come out of. Instructors and course rosters are a legitimate way to meet testers in or just out of training.

One urgency marker: BLS projects employment for the combined trade to change 6.8% from 2025 to 2035, with about 42,000 openings per year on average — churn across the trade that keeps experienced people, the testers among them, moving between shops.

Post where they look, and see what candidates see on the backflow tester jobs page.

Anchor the offer to the Bureau of Labor Statistics numbers — the May 2025 OEWS release, published May 15, 2026 — and name what each number covers, because OEWS publishes the trade as one combined occupation, SOC 47-2152 Plumbers, Pipefitters, and Steamfitters, with no split for specialties like backflow testing.

The defensible figures:

• At plumbing, heating and air-conditioning contractors (NAICS 238220): median $63,010/year, mean $71,800, with the 10th percentile at $43,720 and the 90th at $107,780 — 330,570 jobs.
• Nationally, all industries: median $30.67/hour ($63,800/year), and the middle 50% earn $24.13–$40.92/hour ($50,190–$85,110/year).

Two cautions before you set the range.

First, what OEWS leaves out: the figures exclude overtime pay, shift differentials and non-production bonuses like sign-on bonuses, while including commissions and production bonuses — so a tester who earns heavy overtime can out-earn the table.

Second, the combined series spans the whole trade, not testers alone — treat it as the floor-and-ceiling context for the trade you are hiring from, and let the credential move you within it.

In Texas the gate is explicit: anyone who tests or repairs backflow prevention assemblies must hold the TCEQ BPAT licence, so the tester credential — not the plumber licence — decides who can bill the testing.

And that credential has its own doors: Texas counts water system operation, irrigation and fire-sprinkler work among the experience that qualifies, alongside plumbing.

State figures for your market are on our backflow tester salary page.

Pay plan.

The plan structures that matter for techs — hourly, flat rate, commission, hybrid — and their trade-offs are covered in our guide to the hvac technician pay plan.

For this seat, one fit is worth naming: testing is unit-shaped work (assemblies per day), so a base-plus structure that pays a defined amount per completed, filed test rewards throughput without abandoning the hourly floor — but define "completed" as filed and accepted, not merely tested, or the plan pays for paperwork you never see.

However you structure it, put the credential premium in the base rather than in a bonus the hire can lose: in Texas, the TCEQ BPAT licence is what makes the testing billable at all.

Screen in a fixed order so every candidate clears the same gates — and weight the order toward what the seat actually does all day: test assemblies to a defined procedure, and produce reports that survive an audit.

• 1. Verify the credential before the interview. Collect the credential number with the application and check it with the issuing body itself — the state agency for a state licence, ASSE for the certification. This is the same discipline as any licence check, and it is the single highest-value screen for this seat.
• 2. Make them test out loud. Ask them to walk you through testing an RP assembly: isolating the fixture, the readings they take, what a failing reading looks like, and what they do next. A competent tester narrates a sequence; a credential borrowed from a resume does not survive this question.
• 3. Ask which procedure they test to. ASSE tests to multiple field-test procedures — USC 10th Edition, ASSE, EPA, Illinois, Missouri, one-hose, TREEO — and some jurisdictions require a specific one. The answer you want names the procedure and where they used it. A candidate who says "there's only one way to do it" either has not worked across jurisdictions or is not listening to the water supplier.
• 4. Probe the assembly types. RP, DC, PVB, SVB: what each is, and where they have tested each. If your work includes fire lines or irrigation, ask about those assemblies specifically rather than assuming general coverage.
• 5. Match scope to the job. If the seat includes repairs, have them walk through a rebuild — what they replace first on a failed check, and how they verify the fix. Testing and repairing are separate ASSE standards (5110 and 5130), so verify whichever the job actually demands instead of assuming the card covers both.
• 6. Interrogate the paperwork. Ask what their test reports contained, how and where they were filed, and what they did when a customer disputed a failure. Then ask about the gauge: how they kept the test kit calibrated. Annual test-gauge calibration is a rule our research could not verify from a primary source — it sits with the local water purveyor or code where it exists — so the answer that matters is whether the candidate asked their purveyor rather than assumed.
• 7. Run the trust screens before the offer. The seat enters customers' buildings and signs compliance documents. Whatever background and reference checks you run on field hires, run them here too — before the offer, not after.

None of these is automatically a no — each is a reason to slow down and verify before you offer.

• A credential that can't be looked up. No number, a number the issuing body does not confirm, or a certificate photo instead of a verifiable record. This seat's entire value is a credential someone else can confirm — stalling here is disqualifying in a way it is not for other seats.
• A lapsed renewal explained away. ASSE certifications renew on a three-year cycle, and state licences (Texas BPAT among them) carry their own renewal hours. "They don't really check" is not an answer — it is a preview of how your reports will be handled.
• One-procedure certainty. A tester trained on one field-test procedure who insists it is universal will file nonconforming reports the day your water supplier asks for a different one. The candidates you want know procedures vary by jurisdiction and can name the one they used.
• Assembly talk that doesn't survive follow-ups. Every assembly is a "check valve," the four types blur together, or fire-line and irrigation assemblies are "about the same." Vocabulary gaps at interview become testing gaps on site.
• Scope claims bigger than the card. "Sure, I rebuild them" offered alongside a tester-standard credential, or repair experience that has never touched the assemblies you actually service. Testing and repairing are separate ASSE standards (5110 and 5130), while the Texas BPAT licence covers both — so verify the scope you are hiring, not the scope they describe.
• Fire-line claims that don't match the rule (Texas). A BPAT may work on fire lines only while permanently employed by an Approved Fireline Contractor — a candidate describing independent fire-line testing work in Texas is either leaving something out or describing someone else's licence.
• Casual paperwork. Late filings, reports "recreated from memory," or pride about never failing an assembly. Failing assemblies exist; a tester who has never filed one is not testing long enough or not telling you what happened next.
• The shortcut instinct, said out loud. Jokes about passing marginal assemblies to save the customer a repair bill. You are hiring the person who tells your customer the truth about their drinking water — and whose name sits under the report the water supplier can ask to see.

The 30/60/90 structure and the pre-start paperwork carry over from our guide to onboarding new technicians — what changes is what each milestone checks, because this seat's risk sits in credentials and reports from day one.

Before day 1 — credential and registration.

Verify the credential at the issuing body one more time and record the expiry in your credential tracker.

Then ask each water supplier you report to what they require from a new tester on your account — where the supplier keeps its own tester requirements, it would rather answer the question than reject your first report.

If the hire is a sponsored plumber working toward the credential, map the milestones now: course dates, exam dates, the application window (Texas publishes its eligibility rules and fees openly — use them as the checklist shape) and who pays for which step.

Week 1 — kit, routes, and the purveyor map.

Assign and inventory the test kit, and set its calibration schedule against whatever your water suppliers require rather than a guess.

Ride along to your most-reported accounts and hand over the purveyor map: which supplier, what they require, and by when.

Weeks 2–4 — paired tests, then solo with review.

Pair them on live tests, then let them run solo while you review every report for the first few weeks — readings, assembly details, filing.

This is also when you set the rule that a completed test means filed and accepted, in writing.

Months 2–3 — full territory and a real checkpoint.

Hand over the full testing route, then hold a 90-day review: reports filed on time, failures documented and converted to repair work, zero rejected filings.

Agree on the next credential or endorsement milestone while you are there — this seat has a built-in growth path, which is also your retention lever below.

Retention math is simple for this seat: the credential that makes a tester valuable to you takes documented experience, a 40-hour course and exams to earn — and it travels with them to other employers in your market where it is accepted.

What keeps them:

• Pay for the credential, visibly. The renewal cycle is real work — ASSE recertification adds an 8-hour class, a written exam and a practical every three years (with the written growing from 50 to 100 questions from January 1, 2027), and a state licence like the Texas BPAT renews on 24 CE hours, 8 of them hands-on. Fund the class, the exam and the paid time, and say so in the offer letter. A tester who pays their own renewal is interviewing for your competitor's next job posting.
• A scope ladder. ASSE's backflow series covers five standards — tester (5110), repairer (5130), surveyor (5120), fire sprinkler tester (5140) and program administrator (5150) — a built-in career path inside one specialty. Name the next credential and what earns it: the standard names describe the scope, and — as when you hired — verify whichever the job actually demands rather than assuming the current card covers it.
• A written pay path. The BLS spread at plumbing and HVAC contractors runs from $43,720 at the 10th percentile to $107,780 at the 90th. Wherever the hire sits today, write down the next step and what earns it — a number they have to guess at is a number they will take somewhere else.
• Keep the seat billable. Testing alone can leave calendar gaps; the strongest version of this seat bundles testing with the repair work failed tests surface — and, in Texas, the customer service inspection certifications a WSPS-endorsed plumber may perform. Let the tester own the follow-up on their own failed tests where their scope covers it, and the seat pays for itself in front of you.

Hiring one role well is easier when the rest of the operation is set up for it — our guide to retaining technicians covers keeping a full crew, and our guide to hiring HVAC and plumbing techs covers the cross-role work: job descriptions, pay plans, verification and onboarding that apply to both trades.

This page is employer career and business information, not legal advice. Backflow tester credentials and renewals are set by state agencies (such as the TCEQ in Texas), industry bodies like ASSE and, where local rules apply, your water supplier or local code — confirm the requirements that apply to your company with each issuing body, and consult an employment attorney on pay and employment questions.