Backflow tester license in Arizona: what you actually need

Last updated 2026-08-17

Do you need a license to test backflow devices in Arizona?

Yes, but the word "license" is misleading here. Arizona has no single state-issued backflow tester license managed by one board you can look up. What it has is a system built on ASSE (American Society of Sanitary Engineering) certification standards, primarily ASSE 5110 for potable water systems and ASSE 5115 for reclaimed water systems, enforced at the local water purveyor level ^[1].

The Arizona Department of Environmental Quality (ADEQ) requires that cross-connection control testing be done by a certified tester under its rules ^[2]. That certification has to come from an ASSE-approved testing program. So you are not unlicensed without a state card. You are unqualified to work unless you hold a valid ASSE 5110 or 5115 certificate and the local utility has approved you as a tester.

Most cities and water districts in Arizona, including Phoenix, Tucson, and Mesa, keep their own approved tester lists. Getting on those lists is a separate step after you earn your ASSE certification. Skip it and you cannot legally submit test reports, even with a valid ASSE card in your pocket.

The short answer: yes, you need credentials. They are ASSE-based, locally enforced, and two-layered (ASSE certification plus water purveyor registration). Neither layer is optional if you want to get paid.

What is ASSE 5110 and why does Arizona require it?

ASSE 5110 is the national standard that defines what a backflow prevention assembly tester has to know and prove. It covers the written knowledge exam and the field performance test. ASSE 5115 covers reclaimed water systems, which matter in Arizona given how much the state relies on reclaimed water for irrigation and commercial landscaping ^[3].

ASSE publishes these standards and approves the training programs that certify testers against them. When ADEQ says testers must be certified, it points directly at this framework. Arizona did not invent its own system. It adopted an established national standard and made local water utilities responsible for enforcement.

Confirm the accepted certification standard with each water purveyor, because some accept equivalent programs like AWWA-based training. ASSE 5110 is the most widely recognized credential across Arizona jurisdictions. If you are going to earn one credential and stop, make it ASSE 5110.

How long does getting a backflow tester certification in Arizona take?

From zero to working, most people finish in two to four weeks. The training itself is usually two to three days of classroom and hands-on instruction. The written exam and field performance test often happen at the end of that training period, or within a few days after ^[4].

After you pass, the certifying body issues your ASSE 5110 certificate. That part is typically fast, one to two weeks. Then you register with each water purveyor where you want to test. Purveyor registration timelines vary. Some cities process new tester applications within a week. Others take longer, and a few require you to appear in person or submit notarized paperwork.

Here is a realistic timeline for most Arizona applicants:

Step	Typical time
Find and enroll in ASSE-approved course	1 to 7 days
Complete training and pass exams	2 to 3 days
Receive ASSE certificate	1 to 2 weeks
Register with local water purveyor(s)	1 to 4 weeks
Total, start to first test report	3 to 8 weeks

Nobody should promise you a faster path. Processing times shift, courses fill up, and some utilities are slow. Budget eight weeks and be pleasantly surprised if it takes less.

For the Arizona startup process in more detail, see how to start backflow tester in Arizona.

How much does a backflow tester certification cost in Arizona?

The honest range is $150 to $400 for most applicants. Your total depends on what you already own and which course you pick ^[4].

Breaking it down:

Cost item	Typical range
ASSE 5110 training course (includes exam)	$149, $300
Gauge calibration or equipment rental (if needed for field test)	$0, $75
Water purveyor registration fee	$0, $50 per utility
Certificate renewal (every 3 years, varies by program)	$50, $150

The training course is the biggest variable. In-person courses at trade schools or utility-sponsored programs run $200 to $300 and usually include the field test portion. Online prep courses for the written portion cost less but do not replace the hands-on field exam requirement. ASSEPath sells a one-time $149 ASSE 5110/5115 Tester Kit built to get you through that written exam efficiently if you need to self-study before an in-person field day.

You also need calibrated test equipment to do the field test and to work professionally. If you already own gauges, good. If not, that is a separate cost no course fee covers. Some programs lend equipment for the field test day only.

Confirm current fees with the specific program and with your local water purveyor before budgeting. Fees change, and this article cannot guarantee any current price.

What does the ASSE 5110 exam cover?

The written portion covers the mechanics of backflow prevention, how each device type works, why backpressure and backsiphonage happen, and how to read and interpret test results. You need to know the difference between a reduced pressure zone (RPZ/RP) assembly, a double check valve assembly (DCVA), and a pressure vacuum breaker (PVB), among others ^[1].

The field performance exam makes you connect your gauges to a backflow assembly, run a test using the correct procedure, and record the results. Graders watch for correct gauge hookup, proper sequence, and accurate reading. You cannot fake mechanical understanding in the field portion.

ASSE publishes the standard itself, which spells out exactly what knowledge and skills get tested. The standard is ASSE 5110-2019 (most recently updated) and it is the document approved programs are required to teach to ^[1].

A good prep resource is the USC Foundation for Cross-Connection Control and Hydraulic Research, which publishes technical manuals used in training programs across the country ^[5].

How do you register with Arizona water purveyors after getting certified?

Each water utility, whether it is the City of Phoenix Water Services, Tucson Water, or a small mutual water company, keeps its own approved tester list. You submit an application to each one, attach a copy of your ASSE 5110 certificate, and in some cases pay a small registration fee or undergo a background check.

The City of Phoenix requires backflow testers to register with its Cross-Connection Control program before submitting reports ^[6]. Tucson Water runs a similar process. If you plan to work across multiple service areas, expect to register with each one separately. No statewide reciprocity system handles this for you.

Keep digital copies of your certificate. You will send it to multiple utilities and need it again at renewal. Most ASSE certificates are valid for three years, after which you renew through continuing education or retesting depending on the certifying program.

Serve commercial customers across a county and you may end up registered with five or six utilities. That is normal. It is also why staying organized with your paperwork matters from day one.

Do you also need a plumbing license in Arizona to test backflow devices?

It depends on what you are doing. Testing a backflow assembly, meaning attaching your gauges and filling out a test report, does not require a plumbing license in most Arizona jurisdictions ^[7]. That is the job of a certified backflow tester, and ASSE 5110 is the qualifying credential.

Repairing or replacing a backflow assembly is different. That work typically requires a licensed plumber or pipefitter under Arizona Revised Statutes Title 32, which governs contractor licensing through the Arizona Registrar of Contractors ^[7]. If your business involves both testing and repair, you may need both the ASSE certification and a plumbing contractor license, or you work under someone who holds one.

If you are just getting started as a tester and plan to test only, not repair, the ASSE 5110 route is the relevant one. Confirm the scope of work you intend to offer with the Arizona Registrar of Contractors or a local attorney before structuring your business. The line between testing and maintenance can blur on older or failing assemblies.

How does Arizona compare to nearby states for backflow tester licensing?

Arizona sits in the middle of the national spectrum. It is less prescriptive than California, which runs a more formal AWWA-based program with local utility enforcement, and less regulated than some eastern states that issue actual state licenses for backflow testers ^[8].

Colorado and Nevada are structured much like Arizona, with ASSE certification driving the qualification and local utilities doing enforcement. New Mexico has a comparable setup.

For comparison:

State	Governing framework	State license card?
Arizona	ASSE 5110, purveyor-enforced	No
California	AWWA + local utility programs	No (local control)
Colorado	ASSE 5110, local enforcement	No
Texas	TCEQ-issued backflow license	Yes
Florida	Local program, ASSE recognized	Varies by county

Texas is the outlier in the West and South: the TCEQ issues a state backflow prevention assembly tester license ^[9]. If you are considering operating across state lines, check each state independently. There is no multistate reciprocity for backflow testers the way there is for some professional licenses.

For neighbors in the region, see backflow tester license in California and backflow tester license in Colorado.

What equipment do you need to work as a backflow tester in Arizona?

You need a calibrated differential pressure gauge kit. Most field testers use a four-valve differential gauge built for backflow testing, sometimes called a backflow test kit or a Watts style gauge after one common brand. The gauge has to be calibrated annually by a certified calibration lab. An uncalibrated gauge is grounds for rejecting your test reports.

You also need the valve keys or wrenches appropriate for the assemblies you test, a clipboard and waterproof report forms (or a tablet with a reporting app), and a way to submit reports to the water utility, usually online or by fax depending on the purveyor.

Gauge kits from reputable manufacturers run $300 to $600 new. Calibration costs $50 to $100 per year. Some testers keep two gauges, one for standard testing and a backup. That is optional but smart on a schedule-heavy route.

Do not buy your gauge before passing the field exam. Borrow or rent for the exam if you can. Buy after you know you passed, so you are not sinking money into equipment before the certification is in hand.

How do you renew your ASSE 5110 certification in Arizona?

ASSE 5110 certification renews on a three-year cycle. Renewal requirements vary by which approved program originally certified you, but generally involve either completing a set number of continuing education hours related to backflow prevention or passing a reexamination ^[1].

Some programs accept proof of ongoing work (a log of tests submitted to utilities) as partial credit toward renewal. Others require a formal refresher course. Confirm the renewal path with your certifying organization rather than the utility that approved you, because the utility cannot renew your ASSE certificate. Only the certifying body can.

Let it lapse and you will likely have to restart the full certification process. Utilities drop you from their approved tester lists the moment your certificate expires. Set a calendar reminder 90 days before your ASSE certificate expiration date. That gives you enough runway to find a renewal course without scrambling.

Renewal usually costs $50 to $150 depending on the program, less than initial certification in most cases.

Where to find ASSE-approved backflow tester training programs in Arizona

ASSE International keeps a directory of approved training programs on its website ^[1]. You can filter by state and standard (5110 or 5115) to find courses offered in Arizona. Programs appear periodically at community colleges, trade schools, and through water utility continuing education departments.

The Arizona Water Association (AWA) sometimes lists or sponsors relevant training for its member utilities ^[10]. Local chapters of PHCC (Plumbing-Heating-Cooling Contractors) and UA (United Association of Plumbers and Pipefitters) occasionally run ASSE-approved courses for their members, which may be open to non-members for a fee.

For anyone doing self-study before the formal in-person field exam, the ASSEPath ASSE 5110/5115 Tester Kit at $149 is built for this prep stage. It covers the written exam content so you are ready when the formal training day starts, not reading the material cold.

Pair that prep with the USC Cross-Connection Control Manual, the standard technical reference used in most training programs ^[5], and you arrive on exam day in genuinely strong shape. The field test is where people fail, not the written exam. Spend time on hands-on practice before your exam date if you can find a working assembly to observe or touch.

If you are exploring similar paths in neighboring states, see backflow tester license in Arkansas or how to start backflow tester in California.

Frequently asked questions

Do you need a license for backflow tester in Arizona?

Not a state-issued license in the traditional sense. Arizona requires ASSE 5110 certification for potable water backflow testing and ASSE 5115 for reclaimed water. These certifications come from ASSE-approved programs, and then each local water utility keeps its own approved tester list you must register with separately. Both steps are required before you can legally submit test reports.

How much does backflow tester certification cost in Arizona?

Plan for $150 to $400 total. The ASSE 5110 training course, which includes the written and field exams, typically runs $149 to $300 depending on the program. Water purveyor registration fees add $0 to $50 per utility. Equipment calibration and any gauge rental for the field test may add another $50 to $75. Renewal every three years costs $50 to $150. Confirm current fees with your chosen program.

How long does it take to get a backflow tester certification in Arizona?

Most people go from zero to working in three to eight weeks. Training takes two to three days. Receiving your ASSE certificate after passing takes one to two weeks. Registering with each water purveyor takes one to four weeks depending on the utility. Budget eight weeks and treat anything faster as a bonus. Purveyor processing times are the biggest variable you cannot control.

Does Arizona have a statewide backflow tester registry?

No. Arizona does not maintain a single statewide list of approved backflow testers. Enforcement happens at the water utility level, meaning you register separately with each purveyor whose service area you work in. Cities like Phoenix and Tucson maintain their own lists. There is no central ADEQ or state board registry to check or join.

Do I need a plumbing license to test backflow assemblies in Arizona?

For testing only, generally no. ASSE 5110 certification is the relevant credential for attaching gauges and submitting test reports. Repairing or replacing a backflow assembly is different and typically requires a licensed contractor under Arizona Revised Statutes Title 32. If your work crosses into repair or installation, confirm the licensing requirement with the Arizona Registrar of Contractors before you start.

How often do I need to renew my ASSE 5110 certification?

ASSE 5110 certification renews on a three-year cycle. Renewal involves either continuing education hours related to backflow prevention or a reexamination, depending on which approved program certified you. Let it lapse and utilities will remove you from their approved lists, and you may have to re-certify from scratch. Set a reminder 90 days before your expiration date to find a renewal course in time.

Can I test backflow devices in Arizona with a certification from another state?

There is no formal reciprocity for backflow tester credentials between Arizona and other states. But because ASSE 5110 is a national standard, a valid ASSE 5110 certificate issued by an approved program in another state is generally accepted by Arizona water purveyors. You still register with each local utility. Confirm acceptance directly with each purveyor before assuming your out-of-state certificate transfers.

What type of gauge do I need to work as a backflow tester in Arizona?

You need a calibrated differential pressure gauge kit designed for backflow testing, often called a four-valve gauge or differential gauge. It must be calibrated by a certified lab at least annually. Uncalibrated gauges invalidate your test reports. New kits cost $300 to $600. Calibration costs $50 to $100 per year. Borrow or rent for your field exam before committing to a purchase.

Where can I find ASSE-approved backflow tester courses in Arizona?

ASSE International's website lists approved training programs filterable by state and standard (5110 or 5115). The Arizona Water Association and local PHCC or UA chapters occasionally host courses. Community colleges in metro Phoenix and Tucson periodically offer backflow certification programs. Search the ASSE program directory directly at asse-plumbing.org for the most current Arizona offerings.

Is ASSE 5115 required in Arizona for reclaimed water systems?

Yes. To test backflow assemblies on reclaimed water systems in Arizona, you need ASSE 5115 certification in addition to or instead of ASSE 5110, depending on the scope of work. Arizona relies heavily on reclaimed water for irrigation and commercial use. Check with each water purveyor about their specific requirements for reclaimed water testing, since rules vary by utility.

How many water purveyors do I need to register with in Arizona?

As many as you want to work in. Each utility, whether a city, water district, or private water company, keeps its own approved tester list. If you plan to serve clients across multiple service areas, you register with each one separately. Working metro Phoenix and Tucson alone could mean registering with several distinct purveyors. There is no way around it: each registration is its own paperwork process.

What happens if I submit a backflow test report without being on the utility's approved tester list?

The utility rejects the report. The property owner stays out of compliance and may face fines or water service issues. Your reputation with that utility takes a hit, and getting approved later may be harder. Always confirm your approved status with the specific purveyor before accepting a testing job in their service area, even if you are certified elsewhere.

Is there a background check or insurance requirement to become an approved backflow tester in Arizona?

Requirements vary by utility. Some water purveyors require proof of general liability insurance before adding you to their approved list. A few require background checks. There is no statewide standard on this. Ask each utility for their full application requirements before submitting. Being unprepared for an insurance requirement is a common delay that can add weeks to your approval timeline.

Can a plumbing apprentice or unlicensed helper assist with backflow testing in Arizona?

The certified tester must perform and sign off on the test. An uncertified helper can assist with logistics like carrying equipment, but they cannot operate the test gauges or complete the test record. Submitting a test report signed by a certified tester who was not actually present is a serious compliance violation. Keep your name on tests you personally perform.

Sources

1. ASSE International, Professional Qualifications Standard 5000 series (Backflow Prevention Assembly Tester): ASSE 5110 defines the written and field performance requirements for backflow prevention assembly tester certification; ASSE 5115 covers reclaimed water systems
2. Arizona Administrative Code, Title 18, Chapter 5 (Department of Environmental Quality, Safe Drinking Water): ADEQ requires that backflow prevention assembly testing be performed by a certified tester under Arizona cross-connection control regulations
3. Arizona Department of Water Resources, Reclaimed Water Use: Arizona relies substantially on reclaimed water for irrigation and commercial use, making ASSE 5115 reclaimed water tester certification relevant in the state
4. USC Foundation for Cross-Connection Control and Hydraulic Research: Training for ASSE 5110 typically takes two to three days of classroom and hands-on instruction; total cost for certification ranges from approximately $150 to $400
5. USC Foundation for Cross-Connection Control and Hydraulic Research, Manual of Cross-Connection Control: The USC FCCCHR publishes technical manuals widely used as reference material in ASSE 5110 backflow tester training programs
6. City of Phoenix Water Services Department: The City of Phoenix requires backflow testers to be registered with its Cross-Connection Control program before submitting test reports
7. Arizona Revised Statutes Title 32, Contractors (Arizona Registrar of Contractors): Repair or replacement of backflow assemblies in Arizona requires licensing under ARS Title 32 governing contractor licensing; testing-only work does not require a plumbing contractor license
8. Texas Commission on Environmental Quality, Occupational Licensing: Texas (TCEQ) issues a formal statewide backflow prevention assembly tester license, unlike Arizona which relies on ASSE certification and local utility enforcement
9. Arizona Water Association, Education and Training: The Arizona Water Association periodically lists or sponsors backflow-related training opportunities for water utility professionals in Arizona