# Backflow assembly identifier

Answer from visible features without operating valves. This suggests a possible RP, DC, PVB or SVB type. Confirm the nameplate with a tester. It cannot approve an installation.

Use the tool on the [web page](https://backflowtesters.fyi/tools/backflow-assembly-identifier). It works without JavaScript.

## How to use it

1. Choose which design can you clearly see?.
2. Choose for a double-check body: is there a relief valve between the checks?.
3. Choose for an air-inlet device: which test fittings are present?.
4. Read the result.

## How it works

Features follow the RP, DC, PVB and SVB definitions in the California handbook. PVB uses a loaded air inlet with test cocks; SVB has a test cock and bleed or vent port. RP has a differential pressure relief valve between independently acting checks. DC has independently acting checks without that relief arrangement. California State Water Resources Control Board, Cross-Connection Control Policy Handbook, April 2026, fetched 2026-11-10: https://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/docs/2026/cross-connection-control-policy-handbook-apr-2026.pdf

A possible match is not a definitive identification. Covers and orientation can hide components. Unknown or contradictory answers return no identification. Do not open test cocks, move shutoffs or enter a vault to answer.

PVB and SVB are limited to backsiphonage in the cited definitions. This tool does not select protection, assess hazards, determine approval or replace field testing.

> Identification aid only. Confirm the nameplate with a qualified tester and the utility. Do not operate equipment or change protection based on this result.

## Questions

### Can this tell me which assembly to install?

No. Ask your utility and a qualified designer or installer to assess the hazard and approved protection.

### What if my record says DCDA or RPDA?

These detector variants are outside this tool. Give the full model and bypass details to a tester.