Backflow Listings

The backflow prevention service sector spans thousands of licensed contractors, certified testers, equipment suppliers, and inspection firms operating under state and local regulatory frameworks across the United States. This directory organizes those professionals and businesses into structured entries designed for service seekers, facility managers, and compliance officers locating qualified providers. The Backflow Directory Purpose and Scope page describes the full selection criteria and geographic coverage that govern what appears here.

How to read an entry

Each listing in this directory presents a standardized record structured around five data fields: business name, primary service category, geographic service area, licensing or certification status, and contact reference. These fields follow a consistent format across all entries so that professionals in different states or service niches can be evaluated against the same structural baseline.

Service categories are drawn from the four primary professional classifications in the backflow prevention sector:

1. Certified Backflow Tester — An individual holding a state-recognized or ASSE-certified credential (most commonly ASSE 5000 Series) authorizing them to test, inspect, and certify backflow prevention assemblies. Licensing authority varies by state; in California, the authority flows through individual water purveyor cross-connection control programs; in Texas, through the Texas Commission on Environmental Quality (TCEQ).
2. Licensed Backflow Installer — A plumber or specialty contractor licensed to install backflow prevention assemblies under applicable state plumbing codes. Installation work typically requires a general plumbing license; dedicated backflow endorsements are required in states including Washington and Oregon.
3. Backflow Repair Technician — A professional authorized to repair, rebuild, or replace internal components of testable assemblies such as reduced pressure zone (RPZ) assemblies and double check valve assemblies (DCVA). Repair authorization is distinct from test-only credentials in most state frameworks.
4. Backflow Prevention Equipment Supplier — A distributor or supplier of ASSE-listed, AWWA-standard, or USC FCCCHR-approved backflow prevention assemblies. Supplier listings do not carry licensing fields but may reference product line certifications.

Entries for certified testers include the certifying body where it was submitted by the listed professional. Entries for licensed contractors reference the state licensing board but do not reproduce license numbers in full — those records are verifiable directly through each state's licensing authority.

What listings include and exclude

Listings in this directory cover businesses and individuals whose primary or declared specialty service includes backflow prevention — testing, installation, repair, or supply. General plumbing contractors who offer backflow services among a broad range of trades are included only when backflow prevention is listed as a declared service category in their business profile.

Included:
- Dedicated backflow testing firms
- Plumbing contractors with active backflow endorsements or certifications
- Cross-connection control specialists serving municipal, commercial, or industrial accounts
- Equipment distributors whose inventory centers on backflow prevention assemblies approved under ASSE 1013, ASSE 1015, ASSE 1020, or equivalent USC FCCCHR listing standards

Excluded:
- Unlicensed or uncertified individuals, regardless of claimed experience
- General contractors with no declared backflow service category
- Manufacturers (as opposed to distributors or suppliers)
- Regulatory agencies, water utilities, and municipal authorities — those entities are referenced in the How to Use This Backflow Resource page, which addresses the distinction between enforcement bodies and service providers

Listings do not constitute endorsements. A business appearing in this directory has met the submission threshold for a recognized license or certification reference — it has not been independently audited.

Verification status

Listings carry one of three verification status designations:

• Submitted — The business submitted a profile with license or certification information. The data has not been independently verified against the issuing authority's public records.
• Cross-Referenced — The license or certification number submitted has been matched against a publicly accessible state licensing database or certifying body registry at the time of record creation.
• Lapsed or Flagged — A previously cross-referenced credential has returned a non-active or expired status in a subsequent check against the source database. These entries remain visible with the flag notation so that service seekers are alerted before contact.

ASSE certification status for individual testers can be independently confirmed through the ASSE International online certification lookup. State contractor license status is verifiable through each state's contractor licensing board — for example, the California Contractors State License Board (CSLB) and the Florida Department of Business and Professional Regulation (DBPR) both maintain searchable public databases.

Businesses are responsible for maintaining the accuracy of their submitted data. A Cross-Referenced status reflects a point-in-time check, not a continuous monitoring relationship.

Coverage gaps

The national scope of this directory does not translate to uniform density across all 50 states. States with mandatory third-party annual testing requirements — including California, New York, and Illinois — generate higher volumes of certified tester listings because regulatory pressure sustains a larger, more formally credentialed professional population. States without statewide mandatory testing programs produce thinner listings, even where individual water utilities or municipalities impose their own requirements.

The following structural gaps affect this directory's completeness:

• Rural and low-density areas across states such as Wyoming, Montana, and North Dakota have limited professional representation. Facilities in those regions may need to engage regional or traveling contractors whose listed service area spans multiple counties or states.
• Municipal utility cross-connection control staff — employees of water authorities who perform backflow testing as part of their utility function — are not listed, because they do not operate as independent service providers.
• States undergoing licensing framework transitions may have entries that reflect superseded credential categories. Oregon's backflow certification framework, for example, has undergone revision through the Oregon State Plumbing Board, and some legacy credential classifications appear in older entries.

Service seekers who do not locate a provider in a specific area are directed to state plumbing boards, the American Backflow Prevention Association (ABPA) chapter directory, or the ASSE International member locator as supplementary search resources. The Backflow Listings index is updated on a rolling basis as new submissions are processed and existing records are reviewed.