Short guides written by our testers, covering the questions we hear most on the phone.
All guides
What to Do When You Get a Backflow Test Notice
A step-by-step guide to the annual notice from your water district: what it means, deadlines, and how to get compliant fast.
Read guideWhat Is a Backflow Preventer?
How backflow happens, how the main assembly types stop it, and why California requires annual testing.
Read guideRP vs. Double Check vs. PVB: Which One Do You Need?
Side-by-side comparison of the common assembly types, the hazards each is approved for, and installation rules.
Read guideMore quick answers are on our FAQ page.