I am working with a facility that utilizes low-expansion foam systems, with foam in bladder tanks. They have a hydrant on the property that flows water and foam when opened. What would be the cause of this? Thank you.
Foam system piping is piped to the underground fire hydrant feed,,,
For some reason??
Maybe it is the only hydrant hooked up to the foam system?
Someone thought it was a good idea?
One possible scenario, does this system have a check valve on the underground line coming in to feed this area protected by foam? We had a situation at a plant several years ago where a dry pipe foam system tripped. Owner shuts off fire pump first, then several minutes later shuts off the system valve. So the system was fully charged, along with the bladder. Foam backed up into the underground.
It would seem that a check valve or back flow preventer is non existent or not functional. And mixed foam is leaking back into water supply.
Retrieving data ...