Protection against electrical fire risks

Electrical fires are a significant concern globally, with a substantial portion of building fires originating from electrical sources. In Europe alone, nearly 5000 fire-related casualties occur in domestic buildings each year.

Understanding the root causes and implementing effective mitigation measures is crucial to reducing the risk and impact of these fires.

Frequency and impact of fires of electrical origin

35% of fires in the world start in buildings, according to the International Association of Fire and Rescue Services (CTIF).

In Europe nearly 5000 fire-related casualties occur in domestic buildings, every year, according to Fire Safe Europe (www.firesafeeurope.eu).

Electricity is a very regularly identified cause of domestic fires. Organizations such as the European Fire Academy (EFA), and property and insurance companies that track building damages, declare that 25% of building fires are from electrical source.

Depending on the country and the investigation methods, but also depending on the means of identification, the proportions of electrical fires are:

• 25 % in France (www.promotelec.com)
• 33 % in Germany (www.ifs-kiel.de)
• 40 % in Norway (www.sintef.no)
• 56% of industrial disasters in India are due to electrical faults (www.thehindu.com)

In short, fires in buildings often have dramatic consequences, and electricity is one very frequent cause for these fires. It is therefore essential to analyze the root causes of electrical fires, and to set-up mitigation measures to reduce the risk of occurrence and/or to minimize the consequences.

Origin of electrical fires

If an electrical installation complies with requirements, including the IEC standards, and uses compliant equipment, the risks of electrical fires due to overcurrents, overvoltages and overheating of electrical appliances are reduced below an acceptable level.

However, electrical installations compliance depend on the quality of the job done (assemblies design and manufacturing, on-site work, connections ...), and can also deteriorate over time, often due to environmental factors such as heat and humidity. In addition, damage can occur during use or as a result of chemical reactions (corrosion).

Fig. F73 below illustrates possible locations and causes (other than overcurrents and overvoltages) of electrical fire risks, including for installations compliant to standards.

Fig. F73 – Possible locations and causes (other than overcurrents and overvoltages) of electrical fires in the electrical installation

Solutions to mitigate the risk of electrical fires

The IEC 60364 standard series covers different risks which may be at the origin of an electrical fire, in particular:

• Overcurrent, in IEC 60364-4-43. Refer to Chapter G - Sizing and protection of conductors
• Overvoltage, in IEC 60364-4-44. Refer to chapter J - Overvoltage protection

In addition, the IEC 60364‑4‑42 standard covers the protective measures against «thermal effect», including fire and burns, in case of:

• Insulation failure
• Electric arcs in final circuit conductors and connections (AFDD)
• Assembly internal arc fault (also called arc flash)

Furthermore, you will find examples of state-of-the-art solutions which go beyond the IEC 60364 standard, for additional protection against eletrical fire risks:

• Earth current monitoring and alarming
• Continous monitoring of power connections temperature, inside switchboards, for early detection of abnormal heat rise (faulty power connections are one of the leading causes of fires in low-voltage equipment)
• etc ...

Related technical guides

Electrical Fire Prevention

Do you know how to mitigate the risk of fire in commercial and industrial buildings?
This guide considers the risk of fire caused by electrical currents that fall below overcurrent protection thresholds. It focuses on the latest solutions to help mitigate such hazards in both new and existing installations in commercial buildings.

Download the guide (.pdf)