Portable convection and fan heaters are something commonly found in offices and workplaces during the winter months. Because of the large spaces to heat users simply turn the thermostat up to the maximum which can leave the heater running for periods of several hours. Many of the heaters available to buy are rated at 3000 watts which equates to 13 amps and is the same rating as a standard plug.
Normally when used in the home the thermostat will turn the heater off when the desired room temperature is reached and then back on again when the temperature falls. This on and off pattern effectively allows the plug and flex of the heater to cool in between periods of use. When used to heat large spaces the thermostat is commonly turned up to the maximum and consequently the heater may be running at maximum power for several hours at a time. This high current draw can cause plugs and fuses to get very hot which can lead to them melting.
The photos below are a good example of this type of damage and show some of the items that we found recently when carrying out PAT Testing in Basingstoke.
The above photos show considerable melting and heat damage and serve as a good example of why PAT Testing is an effective way of reducing the risks of fire in the workplace.
If you use portable electric heaters in your workplace we would advise the following simple safety precautions:
Use smaller less powerful heaters rated at around 2000W. These will draw less current and be more comfortably within tolerance of a 13 amp plug.
Set the thermostat to a lower setting so that the heater is not running continuously.
Unplug and check the plug for signs of overheating every day.
Unplug at night or when the building is going to be unoccupied.