Engineered Foam Fire Suppression Systems

Foam Fire Suppression Systems

If your business manufactures, stores, or transports flammable
liquids, a foam fire suppression system may be the appropriate fire
suppression system to fit your needs. Foam systems are also used
in the protection of power generation (coal bunkers), tire and rubber
factories, lumber mills, paper warehouses, and have been
recognized as very effective fire suppression agents for subsurface
injection into hydrocarbon fuel storage tanks.

Firefighting foam is made of three ingredients - a foam concentrate,
water, and air. The concentrate is mixed with water (proportioning),
creating a foam solution. That solution is mixed with air (aspirated)
to produce the foam, which is very fluid, readily flowing over liquid
surfaces. The foam itself is a stable mass of small, air-filled
bubbles with a lower density that oil, gasoline, or water.

Balanced pressure proportioning is the most common method used
for foam system applications. The foam concentrate pressure is
balanced with the water pressure at the proportioner inlet allowing
the proper amount of foam concentrate to be metered into the water
stream.

With an aspirating discharge device, foam solution passes through
an orifice, past air inlets, and into an expansion area to produce
expanded foam. In non-aspirating devices, the foam solution
doesn't mix with air until it first passes through the orifice and
discharge outlet.

Firefighting foam agents suppress fire by separating the liquid fuel
from the air (oxygen) it needs to burn. Depending on the type of
foam agent, this is done in one of several ways;

the foam blankets the fuel surface, smothering the fire and
separating the flames from the fuel surface
the foam cools the fuel and adjacent heat and ignition surfaces
the foam suppresses the release of flammable vapors that
can mix with air.