Water Handling Equipment Guide - National Wildfire Coordinating ...

FOAM GENERATING EQUIPMENT
Foam Proportioners
4. Foam Accessories
b. Portable foam concentrate meter
a. Foam pickup tube
Figure 7—Portable foam concentrate meter.
Figure 6 —Foam pickup tube.
When a foam proportional system intake to the
water stream is on the suction side of the pump, the
pump will lose prime when the foam concentrate is
exhausted or the foam concentrate pickup line
comes out of the supply container. A pickup tube
attachment is available to prevent this. This
attachment has a check valve that is seated when
the foam concentrate is exhausted, preventing the
pump from sucking air and losing prime. This
pickup tube is available commercially and will work
on the suction-side proportioning system and also
on the around-the-pump proportioning system
where this is a frequent occurrence.
The Institute of Geological and Nuclear Sciences
of New Zealand has developed and made
available a direct reading portable foam
concentrate percent meter that can be used to test
a proportioner system in the field. This meter
works by reading the conductivity of the water the
foam solution is being made with. This direct
reading foam concentrate percent meter is called a
Digifoam, and is available commercially.
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