What is a Backflow Preventer Device? 

• A backflow preventer is a device that prevents contaminated water from flowing back into the clean water supply. They come in various forms, from simple air gaps to more complex mechanical assemblies. Backflow prevention is crucial for protecting public water systems from contamination.

Why are backflow preventers important?

• Protecting public water supply:Backflow can introduce contaminants like pesticides, fertilizers, or other hazardous substances into the clean water supply, posing a risk to public health. 
• Regulatory compliance:Many jurisdictions have regulations requiring backflow prevention devices for certain types of installations, like fire protection systems, irrigation systems, and certain commercial or industrial facilities. 
• Preventing contamination:Backflow can occur due to pressure changes in the water system, such as during a water outage or when a sprinkler system is running. 

• Preventing contamination:Backflow can occur due to pressure changes in the water system, such as during a water outage or when a sprinkler system is running. 

What are the different types of backflow preventers?

• Air Gaps:The simplest and most effective method, involving a physical separation between the water outlet and the receiving vessel. 
• Double Check Valve Assemblies (DCVA):These are used in lower-risk situations and ensure water only flows in one direction. 
• Reduced Pressure Principle Assemblies (RPPA):Provide the highest level of protection and are commonly used in fire protection systems and other high-hazard applications. 
• Atmospheric Vacuum Breakers:Designed for non-potable systems and must be installed above the usage point. 
• Pressure Vacuum Breakers:Can be used under continuous pressure and are suitable for multi-zone lawn sprinkler systems.

What is backpressure?

• Backpressure backflow is the reversal of normal flow in a system due to an increase in the downstream pressure above that of the supply pressure.

What factors can cause a backpressure backflow condition? 

• Backpressure backflow is created whenever the downstream pressure exceeds the supply pressure which is possible in installations such as heating systems, elevated tanks, and pressure producing systems. An example would be a hot water space-heating boiler operating under 15-20 lbs. pressure coincidental with a reduction of the city water supply below such pressure (or higher in most commercial boilers). As water tends to flow in the direction of least resistance, a backpressure backflow condition would be created and the contaminated boiler water would flow into the potable water supply.

How often should backflow preventers be tested?

• Annual testing:Backflow prevention devices typically require annual testing by a certified backflow assembly tester to ensure they are functioning properly. 
• After repairs or maintenance:Any repairs or maintenance on a backflow preventer should be followed by a retest by a certified tester. 

What happens if a backflow preventer fails a test?

• Repairs or replacements:A failed test usually indicates that the backflow preventer needs to be repaired or replaced. 
• Follow-up testing:After repairs, the backflow preventer must be retested by a certified tester to ensure it is functioning properly.