Fire Prevention

Are You Ready For A Fire?

Fire is one of the most common disasters. Fire causes more deaths than any other type of disaster. But fire doesn’t have to be deadly if you have early warning from a smoke detector and everyone in your family knows how to escape calmly.

How A Fire Starts

Fire is a chemical reaction involving rapid oxidation or burning of a fuel. It needs three elements to occur:

fuelFUEL – Fuel can be any combustible material – solid, liquid or gas. Most solids and liquids become a vapor or gas before they will burn.

oxyOXYGEN – The air we breathe is about 21 percent oxygen. fire only needs an atmosphere with at least 16 percent oxygen.

heatHEAT – Heat is the energy necessary to increase the temperature of the fuel to a point where sufficient vapors are given off for ignition to occur.

chemCHEMICAL REACTION – A chain reaction can occur when the three elements of fire are present in the proper conditions and proportions. Fire occurs when this rapid oxidation, or burning takes place.Take any one of these factors away, and the fire cannot occur or will be extinguished if it was already burning.

 

How Fires are Classified

aCLASS A Ordinary combustibles or fibrous material, such as wood, paper, cloth, rubber and some plastics.

bCLASS B Flammable or combustible liquids such as gasoline, kerosene, paint, paint thinners and propane. 

cCLASS C Flammable or combustible liquids such as gasoline, kerosene, paint, paint thinners and propane. 

d

CLASS D Certain combustible metals, such as magnesium, titanium, potassium and sodium. These metals burn at high temperatures and give off sufficient oxygen to support combustion. They may react violently with water or other chemicals, and must be handled with care.

 

How to Prevent Fires

imgaClass A — Ordinary combustibles:

  • Keep storage and working areas free of trash Place oily rags in covered containers.

imgbClass B — Flammable liquids or gases:

  • Keep flammable liquids stored in tightly closed, self-closing, spill-proof containers. Pour from storage drums only what you’ll need.
  • Don’t refuel gasoline-powered equipment in a confined space, especially in the presence of an open flame such as a furnace or water heater. 
  • Don’t refuel gasoline-powered equipment while it’s hot.
  • Store flammable liquids away from spark-producing sources.
    Use flammable liquids only in well-ventilated areas.

imgcClass C — Electrical equipment:

  • Utility lights should always have some type of wire guard over them. Heat from an uncovered light bulb can easily ignite ordinary
    combustibles.
  • Look for old wiring, worn insulation and broken electrical fittings. Report any hazardous condition to your supervisor.
    Prevent motors from overheating by keeping them clean and in good working order. A spark from a rough-running motor can ignite
    the oil and dust in it.
  • Don’t misuse fuses. Never install a fuse rated higher than specified for the circuit.
    Investigate any appliance or electrical equipment that smells strange. Unusual odors can be the first sign of fire.
    Don’t overload wall outlets. Two outlets should have no more than two plugs.

imgdClass D — Flammable metals:

  • White phosphorus is air-reactive and will burn/explode on contact with room air. It must be kept in a sealed container with a non-reactive solution to prevent contact with air. All of these metals are not uncommon in labs on the OU campus, but are generally only found in small quantities and accidental fires/reactions can be controlled or avoided completely through knowledge of the properties of the metals and using good judgement and common sense.
  • If you are planning a research project using a large amount of flammable metals you should consider purchasing a five or ten pound container of Class-D extinguishing agent as a precaution.
  • Flammable metals such as magnesium and titanium generally take a very hot heat source to ignite; however, once ignited are difficult to extinguish as the buring reaction produces sufficient oxygen to support combusion, even under water.
  • In some cases, covering the burning metal with sand can help contain the heat and sparks from the reaction. Class D exinguishing agents are available (generally as a dry powder in a bucket or box) which can be quite effective, but these agents are rare on the campus.
  • Pure metals such as potassium and sodium react violently (even explosively) with water and some other chemicals, and must be handled with care. Generally these metals are stored in sealed containers in a non-reactive liquid to prevent decay (surface oxidation) from contact with moisture in the air.
  • White phosphorus is air-reactive and will burn/explode on contact with room air. It must be kept in a sealed container with a non-reactive solution to prevent contact with air. All of these metals are not uncommon in labs on the OU campus, but are generally only found in small quantities and accidental fires/reactions can be controlled or avoided completely through knowledge of the properties of the metals and using good judgement and common sense.

 

When not to fight a Fire

Never fight a fire:

  • If the fire is spreading beyond the spot where it started
  • If you can’t fight the fire with your back to an escape exit
  • If the fire can block your only escape
  • If you don’t have adequate fire-fighting equipment

In any of these situations

DON’T FIGHT THE FIRE YOURSELF.
CALL FOR HELP.