What should be monitored during the use of an AFFF extinguisher?

Monitoring the duration of discharge when using an AFFF (Aqueous Film Forming Foam) extinguisher is crucial for effective fire suppression. AFFF extinguishers contain a foam agent that is designed to blanket and smother flammable liquids, and the effectiveness of the foam is often time-sensitive. Ensuring that the extinguisher is discharged for an adequate duration allows the foam to properly form a barrier over the burning surface, preventing re-ignition and effectively controlling the fire.

In the context of firefighting, the discharge time has to be carefully controlled to ensure that the operator can effectively combat the fire without exhausting the extinguisher prematurely. If the discharge is too short, there may not be enough foam applied to achieve effective suppression, leading to a possible resurgence of the fire.

While monitoring the weight, temperature, and foam expansion rate of the extinguisher are important for maintenance and operational readiness, they do not directly impact the immediate action of suppressing a fire during use.