How often should backflow be tested? The water supplier or local program sets that interval. The 2003 EPA manual says local rules may change its guideline procedure, so there is no single nationwide interval in the passages reviewed.
What to do instead of guessing
Check the water supplier, local program, or property requirements for the interval, then use a record tool to keep the test report details in one place. Backflow Record helps store the information you enter as a report record, and you can also review assembly record, backflow assembly test, and FAQ for related guidance.
Why pages disagree
Pages can disagree because local municipal, county, and state requirements may amend or replace the EPA guideline procedure. The EPA also defines a cross connection as an actual or potential connection between a drinking water system and another supply or source that could contaminate it, and it defines backflow as flow into potable water pipes from a source other than the intended source. That is why one general answer may not fit every program, so start with your local instruction set and then review the broader guides if you need context.
A report in Backflow Record is a record you fill in. It is not a substitute for a licensed tester or for the form your water supplier requires. It does not report an inspection result, and it does not mean a plumbing rule was met.