Question

explain the mechanism & working of a fire extinguisher

Answer 1

Dear Student,

A fire extinguisher is an active fire protection device used to extinguish or control small fires, often in emergency situations. It is not intended for use on an out-of-control fire, such as one which has reached the ceiling, endangers the user, or otherwise requires the expertise of a fire brigade.

Most fire extinguishers contain either water, foam, powder, or carbon dioxide. A fire can be extinguished by cooling it, for which we use water, foam, or carbon dioxide. Or it can be extinguished by smothering it, for which we use foam, powder, or carbon dioxide. The fire extinguisher is designed to get these contents spread over the fire as quickly and safely as possible.

WATER

• First the extinguisher is almost filled with water, then compressed nitrogen is pumped in.
• It now contains water under pressure.
• When the safety pin is pulled out, the handles can be squeezed together, and a valve opens just inside the hose.
• Water under pressure is forced through the valve, through the hose, and out.
• Some water extinguishers are 'jet' type where the water comes out as though from a hosepipe, some are 'spray' type, see foam for how spray is made.

Regards