Matching Fire Class to Extinguisher
| Class | Fuel | Typical example on a job |
|---|---|---|
| A | Ordinary combustibles | Wood cribbing, pallets, cardboard packaging |
| B | Flammable liquids and gases | Diesel, hydraulic oil, propane |
| C | Energized electrical equipment | Generators, panels, crane electrical systems |
| D | Combustible metals | Magnesium or titanium shavings in a shop |
| K | Cooking oils and fats | Site kitchens and break-room fryers |
The PASS Technique
Once you've decided the fire is small enough to fight and you have a clear exit behind you:
Pull
Pull the pin, breaking the tamper seal.
Aim
Aim low, at the base of the fire, not the flames.
Squeeze
Squeeze the handle steadily to release the agent.
Sweep
Sweep side to side across the base until it's out, then watch for re-ignition.
Course Objectives
Match extinguisher types to fire classes and explain what happens when they're mismatched
Apply the PASS technique on incipient-stage fires
Make the fight-or-evacuate decision quickly and correctly
Inspect extinguishers and spot units that won't work when needed
OSHA Training Expectations
Where an employer provides portable extinguishers for employee use, 29 CFR 1910.157 requires an educational program on extinguisher use and the hazards of incipient-stage firefighting — at initial employment and at least annually. It also calls for monthly visual inspections and annual maintenance checks. In construction, 1926.150 sets fire protection rules, including extinguisher placement.
The inspection lesson turns the monthly check into a habit anyone can do: the unit is in its assigned spot and unobstructed, the gauge needle sits in the green, the pin and tamper seal are intact, the hose and nozzle are clear, and the tag shows a current annual service. Anything off gets reported and swapped before the next shift.
Online training covers the knowledge part well. Some employers also run a live-fire or simulator session so workers feel the discharge and range of a real unit; that hands-on piece is up to your employer.
Mobile cranes and boom trucks commonly carry an extinguisher in or near the cab, so operators should know which class it is rated for before they need it. Operators preparing for certification can review equipment requirements in our crane exam prep courses.
Recommended For
- Crane and equipment operators
- Welders and hot work fire watches
- Fuel truck drivers
- Shop and yard workers
- Building and facility staff
- Facility managers
Fight or flee is a real decision
The course teaches when not to fight: a fire that's spreading, smoke filling the area, the wrong extinguisher, or no clear exit. Evacuating and sounding the alarm is always a correct choice.