Fire safety guidance
Fire is potentially the most serious hazard that the University faces. The magnitude and rate of damage to life and property far outweighs any other hazard. It is thus appropriate that the University provides significant resources to reduce the risk of a fire occurring and, if it does occur, to mitigate its damaging effects.
A major factor in the management of fire risk is to ensure that University members work in such a manner as to prevent a fire and to respond correctly if it occurs.
Poor housekeeping, carelessness and neglect will both increase the possibility of a fire occurring and allow a fire to spread more rapidly.
Because fire is a relatively infrequent occurrence, these objectives can be achieved only by motivating staff to be concerned about fire and by thorough training in the actions they must take in the event of fire.
Employees must be made aware that safety is a prime University objective and that unceasing efforts are made to improve safety standards. Staff should also be encouraged to report fire safety problems and to suggest remedial actions.
In this guidance:
Fire is a spectacular example of a fast chemical reaction (oxidation) between a combustible substance and oxygen accompanied by the evolution of heat. The control of fire provided man with his first means of advancement. It broadened his food choice by enabling him to cook, it widened his living range by providing him with an external source of heat, it improved his tools by permitting him to extract and work with metals and it lengthened his day by giving him a source of light. Primitive man used fire and worshipped it but he also went in fear and dread of its destructive nature.
Only three things are needed to start a fire; fuel, oxygen and heat. Removal of any one of these will cause the fire to go out. This fact is used as a basis in the design of fire extinguishers.
Almost all organic materials whether in the solid, liquid or gaseous form are potential fuels. Examples include paper, wood, plastics, natural and man-made fibres, petrol, oil, coal and living tissue. Most inorganic materials are not flammable (eg common salt) although exceptions are hydrogen, sulphur, phosphorus, magnesium and aluminium.
The main source of oxygen in a fire is air (21% oxygen). Other sources are oxidising agents (egs hydrogen peroxide, sodium chlorate and nitric acid) and combustible substances containing oxygen (eg ammonium nitrate).
Heat energy from an external source such as a burning match, a fire, a hot bearing, friction, sparks or a lamp bulb provides means of ignition, as does electrical energy (electrical discharge or static) and spontaneous combustion.
Fire prevention is the concept of preventing outbreaks of fire, of reducing the risk of fire spreading and of avoiding danger to persons and property.
Fire precautions are the measures taken to provide fire protection in buildings, etc, to minimise the risk to the occupants, contents and structure from an outbreak of fire.
Fire protection is the use of design features, systems or equipment in buildings and other structures to reduce the danger to persons, property by detecting, extinguishing or containing fires.
Classification of fires
There are FOUR main classes of fires, these are:
Class 'A' fires
Fires involving solid materials, usually of an organic nature, in which combustion normally takes place with the formation of glowing embers, e.g. wood, cloth, paper.
Cooling by water is the most effective way of reducing the temperature of these burning materials.
- Class ‘A’ materials are generally present in all premises.
Class 'B' fires
Fires involving liquids or liquefiable solids, oils, petrol, greases and fats, where the blanketing or smothering effects of agents which exclude oxygen are most effective.
Class 'C' fires
Fires involving gases.
Class 'D' fires
Fires involving metals.
Fires involving electrical equipment
There is no classification for “Electrical Fires”, as these are normally fires in materials or equipment where electrical voltages are present. Such fires will fall within the categories above.
- Smoke inhalation: The commonest cause of death from fire. Modern plastics, including upholstery foams, burn fiercely with the production of cyanide and halogenated hydrocarbon classes of vapour, which are extremely toxic. Even exposure to concentrations insufficient to cause death can result in lung damage or other prolonged illness. In addition, the smoke is narcotic, and can result in disorientation to an extent which makes successful escape from danger less likely.
- Heat: The heat given off by flame can be intense, especially in a confined space, and can give rise to serious burning of exposed flesh. It can also cause panic and disorientation. However, the smoke and gases from even a small fire can reach in excess of 1000°C, and if inhaled can destroy lung tissue, rendering death inevitable.
- Burning: Direct contact with flame will lead to progressively greater degrees of burning dependent upon the temperature of the flame, duration of contact etc. Similarly, contact with hot fluids such as melted plastic, hot oil etc. will cause severe burning. Generally, third degree burning over more than 60% of the surface of the body is likely to prove fatal as a result of fluid loss and the resultant shock.
Damage to property
- Primary damage: The burning effect of the fire will self-evidently cause damage to combustible and distortable materials. However, this may be limited by fire-fighting activities to a particular area, and even within that area, much may be recoverable - for example, stacked books and files may be superficially damaged but may have much or all of their important internal material preserved by the insulating effect of their covers. Papers and valuables in specially-constructed safes are also often preserved virtually undamaged.
- Secondary damage: More extensive damage is often done by smoke and by the runoff of water from the fire-fighting process. Modern, professional fire-fighting aims to minimise the latter, but smoke damage can destroy more property than the fire itself.
- Waterborne: Fires involving chemicals and fluids can often be a source of waterborne pollution. Primary chemicals and combustion products can become dissolved in the fire-fighting water and run off into the drainage systems. Burning fluids, their containment destroyed, can also enter the drainage system. From here the pollution can escape to water-courses or into the sewerage systems.
- Airborne: Smoke-borne pollutants can affect a wide area. Toxic vapours released as a result of fire damage can also affect wide areas, sometimes necessitating the implementation of emergency Civil Defence-type procedures (e.g. the Flixborough fire).