The Wrong Extinguisher Can Make a Fire Worse

Most workplaces have fire extinguishers on the wall, and most of them have a tag showing a recent service date. Far fewer have asked whether each extinguisher is the right type for what is actually burning nearby. In a real fire, the wrong one wastes the only seconds that matter — and in some cases makes the fire spread.

Matching the extinguisher to the hazard

• Water works on ordinary combustibles such as paper, wood and textiles. Used on burning oil or fat it can throw burning liquid across a room, and used on live electrical equipment it can conduct.
• Foam suits flammable liquid fires such as fuel and solvent spills, as well as ordinary combustibles.
• Carbon dioxide is the usual choice for electrical equipment and server rooms. It leaves no residue, but it does not cool much, so a fire can reignite, and it displaces oxygen in small enclosed rooms.
• Dry powder covers a wide range, including flammable gas fires, but it obscures vision in enclosed spaces and the residue damages electronics and machinery.
• Wet chemical is designed for cooking oil and fat fires in commercial kitchens, where other types can cause a violent flare-up.

A typical site needs a mix. Kitchens, generator rooms, electrical rooms, fuel stores and offices each call for different choices, and a building that has one type everywhere almost certainly has the wrong type somewhere.

What a monthly check should confirm

A formal service by a competent technician is normally annual. Between services, a simple visual check each month catches most problems:

• The extinguisher is in its marked location, visible, and not blocked by stock or furniture.
• The pressure gauge, where fitted, reads in the green zone.
• The safety pin and tamper seal are intact.
• There is no visible damage, corrosion, or a cracked or blocked hose.
• The instructions face outwards and can be read.

People, not just equipment

An extinguisher is only as useful as the person holding it. Staff need to know which type to pick up, how to use it, and — most importantly — when not to fight a fire at all but to raise the alarm and leave. Short hands-on training does far more than a poster on the wall.