How to Use a Wet Chemical Extinguisher

Wet chemical fire extinguishers are used on deep fat fryer fires and fat fires (Class F), although some can also be used on A class fires (solids).

Only tackle small fires with an extinguisher. If the fire has taken hold do not fight the fire but evacuate immediately and warn others of the fire, then call the fire and rescue service. If you tackle the fire make sure you stay at a safe distance and follow the instructions below.

1. Turn off the heat source if it is safe to do so.
2. Ensure you remain at a safe distance from the fire and remove the safety pin (Fig.3), this will also break the tamper seal.
3. Hold the lance at arm's length, with the nozzle above the fire.
4. Squeeze the lever slowly to begin discharging the extinguisher.
5. Apply the fine spray in slow circular movements, this allows the wet chemical agent to fall gently onto the surface of the fire and helps to prevent hot oils or fats splashing the user or spreading the fire.
6. Discharge the entire contents of the extinguisher to ensure that all of the fire has been extinguished, the wet chemical formula helps to prevent re-ignition. The foam blanket stops supply of oxygen to the fire and cools the hot fats and oils.

Reviewed: 20/12/2019 (doc:20 V2.0). Our articles are reviewed regularly. However, any changes made to standards or legislation following the review date will not have been considered. Please note that we provide abridged, easy-to-understand guidance. To make detailed decisions about your fire safety provisions, you might require further advice or need to consult the full standards and legislation.