Fire Prevention and Life Safety
Fire chemistry and classes
Fire needs fuel, heat, oxygen, and the uninhibited chemical chain reaction. Classes: A - ordinary combustibles such as wood, paper, and cloth; B - flammable liquids and gases; C - energized electrical equipment; D - combustible metals; K - cooking oils and fats. Matching agent to class matters: water on a Class B fire spreads it, and water on a Class C fire creates shock risk. Class K requires a wet chemical agent.
Extinguishers
Use PASS: Pull the pin, Aim at the base of the fire, Squeeze the handle, Sweep side to side. Fight only a small, incipient fire, with the correct extinguisher, your back to an exit, and a clear escape route. If the fire is larger than you or smoke is building, evacuate and close doors behind you.
Life safety systems
Know what is monitored: smoke and heat detection, pull stations, sprinkler and standpipe systems, fire doors, exit signage, emergency lighting. Fire doors must never be propped; exits and egress paths must stay clear; extinguishers must be visible, charged, and inspected. Report damaged or blocked life-safety equipment immediately.
Traps
Elevators during a fire, re-entering before the fire department releases the building, assuming a silent alarm is a false alarm, and treating sprinkler discharge as the only sign of fire.
Rule of thumb
Sound the alarm, evacuate, call the fire department - and only then, if trained, if the fire is small, and if you have an exit, attempt extinguishment. Life safety outranks property every time.