According to the Institute for Loss Prevention and Loss Research (IFS), one third of fires have been caused by electricity or a cable fire for almost 15 years. These fires often occur in private homes, where there is no mandatory regular testing of electrical equipment as there is in the commercial sector. Smouldering fires are particularly treacherous, as they are hidden in the wall, yet give off gases and can turn into an open fire on contact with oxygen and consequently lead to flat fires.
How a cable fire starts
A cable fire occurs when an electrical installation or an electrical conductor heats up excessively, which can lead to a fire or smouldering fire, sometimes also in connection with a power failure. The cause is usually a thermal overload of the conductor, which results in excessive heating.
Causes of cable fires:
- A cable break can be the cause of cable fires, because too high current densities occur in the corresponding area of the cable (cable cross-section too small for the flowing current). As a result, the cable heats up strongly and the insulation is damaged, which leads to short circuits and can end in a cable fire.
- Loose plug and clamp connections can also cause a cable fire, as the contact point here is also very small and can heat up considerably.
- Due to age, cables wear out due to oxidation as well as corrosion, which can also cause cable connections to loosen over time. The high temperatures can burn the processed plastics. This can produce toxic and flammable gases and vapours, which in turn can also cause a fire.
- Power strips are often the cause of cable fires, as they can be overloaded by connecting multiple sockets. Although these do not necessarily end in a fire, they can consistently weaken the power lines and their substance over a longer period of time. For example, high currents lead to increased heat stress, which causes the insulation of the cables to become porous. This increases the risk of a smouldering fire over time, which can remain undetected for a long period of time, especially in walls.
- Poorly processed products that do not comply with current safety standards can also be a risk factor and lead to electronic fires / cable fires.
- Lightning can also cause cable fires.
Preventing cable fires
It is helpful to check the insulation because, for example, kinked or crushed cables heat up at the corresponding points. This causes damage to the sheathing, which can result in short circuits. Furthermore, overloading of the cables should be avoided. This includes, among other things, fully loaded multiple sockets or multiple branched socket strips, electric heaters and, for example, not exceeding the specified power of lamps. Defective contacts and other problems such as loose contacts can lead to overheating and smouldering fires, which is why such contacts should be repaired. A thermographic inspection using a thermal imaging camera can be used to examine electrical equipment and installations and determine their surface temperature.
Air quality monitoring for cable fire prevention
The consequence of a cable fire can be a fatal flat fire that destroys the entire flat or house. Smoke alarms do help at this point and save lives - e.g. if the fire starts at night when everyone is asleep. However, smoke detectors generally only go off when the fire has already started.
It would be better to detect the fire before it breaks out, i.e. during its development. In a developing cable fire, various typical gases are released into the room air. These include - depending on the type of insulation - nitrogen dioxide, particulates and VOCs. If these can be detected, an advance warning would be possible.
The air-Q can detect and recognise even the smallest changes in the air quality of a room. If the levels of the substances mentioned increase for a short time or over a longer period of time, although no other known source is present, then a reaction should be taken as quickly as possible to avoid a possible fire. Thus, the air-Q is not only a very sensitive smoke detector and carbon monoxide detector, but also becomes a fire prevention sensor.
