Fire; the Sources of Ignition

For a fire to break out, a combination of three factors are required: sources of ignition, fuel and oxygen. When these occur together, in close proximity, the risk of fire increases dramatically.

Sources of fuel tend to be substances like wood, paper, powder, foam, waste, chemicals or furniture. Sources of oxygen can include items such as tanks of compressed oxygen, yet the air we breathe is also a source that can be involved in igniting or fuelling a fire.

Ignition can come from a number of sources, and understanding the processes involved is absolutely crucial in fire prevention and safety. A source of ignition can be described as, “any object, process or event capable of igniting or transmitting a medium to prompt combustion”. Within this definition, a source of ignition could include open flames, hot surfaces, friction, sparks and static electricity.

But what does this mean in real life? How do you know what might be at risk of igniting a fire?

Hot surfaces

Any equipment that heats up, whether deliberately or as a by-product of the energy used, can be a potential source of ignition. Heaters are an obvious risk in these circumstances. Their surfaces can become hot, and they are blowing or transmitting heated air around a room. Gas and oil heaters also contain a source of fuel directly within them, potentially increasing the risk they pose.

Boilers and cooking equipment are also common tools that are well known to heat up on the surface, as well as inside. But lights and many other kinds of electrical equipment are prone to getting warm on the surface, and should be taken into account when a risk assessment is being carried out.

Sparks

Electrical equipment can be a hazard in more than one way: it can produce not only heat but also sparks that could ignite a fire. Items grinding together, and electrical switches can also be responsible for sparks in a workplace.

Open flames

Cooking equipment, welding gear, or boilers with pilot lights can be sources of open flames. And as well as the risks posed by this kind of equipment, individuals should also be aware that carrying a cigarette lighter or box of matches in their pocket could ignite a fire, if the environmental circumstances are right. For employees working specifically in high-risk areas, it can be wise to publish guidelines about what can be carried on the person.

Areas provided for employees or members of the public to smoke, such as smoking shelters, should always be located a long way from potential sources of fuel. Open flames, burning paper and tobacco embers pose a considerable danger, especially if there is no easy way for people to extinguish their cigarettes. If smoking areas are kept at a distance from buildings and other potential sources of fuel, they can usually be maintained relatively safely.

To maximise safety and minimise the risk of a fire, all sources of ignition should be identified and accounted for when a fire risk assessment is being carried out, and employees should be trained in the risks and hazards they face in their day-to-day work. Electrical equipment should undergo regular safety checks to reduce the risk of sparks and malfunction, and committing to keeping sources of ignition separate from sources of fuel and oxygen will produce long-term safety benefits for any work premises.