What is Backflow?
Backflow is when water flows in the opposite direction of where it should be going. Backflow happens in a fire sprinkler system when water from the sprinkler line flows back toward the municipal water source.
Why are Backflow Preventers Needed?
The job of a backflow preventer is to stop water from flowing back through a sprinkler line and into the city’s water source. Backflow preventers keep dirty water from getting into water supplies. The water in fire sprinkler pipes has been sitting there for a long time, and it could be harmful to drink.
Types of Backflow Preventers
For fire protection systems, there are two common types of backflow preventers:
- Double Check Valve Assembly:- This type of backflow preventer is used in traditional, low-risk fire protection applications.
- RPZ Valve Assembly:- The RPZ backflow preventer is used in situations with a high risk, like when there are chemicals around.
Inspections and Testing for Backflow Preventers
Backflow prevention devices need to be tested and inspected to make sure your fire protection system works well. A certified backflow tester should do the testing of the backflow preventer. The testing must be written down and follow NFPA and local rules. Backflow prevention devices should be checked visually once a week or once a month for signs of damage. There are two common kinds of tests that are done on backflow preventers:
- Forward Flow Test:- According to NFPA 25, forward flow tests are done once a year at the system’s designated flow rate, including hose demand, when hydrants or indoor hose stations are located downstream of the backflow preventer. If a way to test isn’t set up for maximum demand, the test must be done at the highest flow rate possible. This test sees if the system can get enough water in the event of a fire.
- Backflow Performance Test:- This test checks how well your backflow prevention devices work to make sure that the water supply is safe from contamination from other sources. This test is done after the forward flow test, based on what the authority in charge says needs to be done.
Check your local or state laws to find out how often and what kinds of backflow prevention testing are needed in your area and for your type of fire protection system.