scope:

This standard sets performance requirements for commercial entities providing evaluations of installed foam system proportioning accuracy.

Purpose

Water equivalency proportioning and test liquid proportioning are methods of assessing the accuracy of an installed foam proportioning system without having to use the actual foam concentrate. This is intended to mitigate logistical difficulties resulting from the need to dispose of the foam solution produced in traditional proportioning tests. The use of water equivalency proportioning or test liquid proportioning should facilitate initial acceptance and annual testing of foam systems to verify their readiness. Such testing must be conducted with substantial discipline by properly trained personnel to be accurate and representative of the true performance of the proportioner. All such testing requires a baseline acceptance test in which the foam concentrate (or a proxy test liquid) is actually proportioned into water to establish performance of the proportioning system in its installed state. This baseline acceptance is then repeated using water or a test liquid in lieu of the concentrate. Since it can be reasonably assumed that any change in the true proportioning rate would be signaled by a change in the water equivalency proportioning rate or the test liquid proportioning rate, subsequent annual testing can be performed without flowing the concentrate, unless there is a substantial change in the water proportioning rate or test liquid proportioning rate.