Fire hazards A fire hazard situation is created when there are risks of harm and damage to people and property respectively, due to fire. There are many ways through which fire hazards can cause fires to start. However, the general principle for a fire to start is, when there is a combination of the following three sources: ignition source, fuel and oxygen.
Sources of ignition include any source of heat that can get hot enough to ignite materials. Some examples are: * Hot surfaces * Naked flames and hot gases * Mechanically created sparks in grinding or frictional processes for example. *Poor electrical installations; damaged cables * Electromagnetic fields from high frequency installations. * Ionizing radiation * Chemical reactions whereby heat is developed.
* Chemical substances * Lighting equipment (Henkel, 2001) Anything that burns easily can be seen as a source of fuel. In an educational institution, some sources of fuel may include the following: * Flammable gases and liquefied petroleum gas * Flammables liquids, solvents and chemicals * Paper and books * Teaching materials * Waste products and litter * Cleaning agents * Carpet tiles. (HM Government, 2006) The major source of oxygen is air.Air is present in an enclosed building and can be introduced or extracted to and from the building through the use of extraction systems.
Additional oxygen can be provided by oxidizing chemicals and from gas cylinders used to store oxygen. Below is a list of some other common fire hazards. (HM Government, 2006) * Electrical hazards * Broken sockets and switches * Faulty plugs * Overloaded sockets and circuits * Problems with lighting fixtures * Inadequate insulation of cables * Housekeeping hazards * Trash and scraps * Sawdust * Obstructed emergency exits * Friction hazards * Damaged machine parts * Insufficient lubricantWrong adjustment for moving parts of machine * Process or operation-related hazards * Work operations involving the use of open flame and which create spark, for example: welding. * Ignition of combustibles due to molten metal.
* Operations involving the evolution of flammable vapors. * Storage hazards * Insufficient ventilation in chemical store rooms for example. * Failure to store incompatibles separately in different storage cabinets. * storage of flammables near to heat. Smoking hazards * Not taking into account "No Smoking" signs.
* Smoking in chemical store rooms or near to flammables * Throwing cigarettes or matches everywhere Henkel, 2001) 2. 3 Classes of fire When fghting fires, it is necessary to choose the right type of fire extinguisher. The choice of the fire extinguisher is based on the class of fire which depends upon the material being burnt in the fire. Table 1 gives a summary of the classes of fire and the type of burning material or fuel source.
