Electrical fires: what causes them and how can we fight them?

Electrical fires are one of the main causes of incidents in industrial warehouses and commercial buildings. These incidents occur due to failures in electrical installations, which are crucial for the operation of the building and its machinery. The rapid and dangerous nature of these fires presents a significant risk to the safety of structures, assets, and people. Therefore, it is essential to understand the causes and appropriate preventive measures to combat and avoid them.

What will you learn in this article?

• How to identify an electrical fire
• The main causes of electrical fires
• How to prevent an electrical fire from starting
• The best systems for preventing and extinguishing a fire

How to Identify an Electrical Fire

Identifying an electrical fire can be complex, as it often starts in hidden areas like walls or ceilings, where electrical cables are installed. Common signs of an electrical fire include:

• Burning smell or melted plastic: This can indicate that the cables are overheating.
• Sparks or visible flames: These are clear signs of a serious electrical failure.
• Electrical supply interruptions: Sudden or unexplained outages may indicate problems in the electrical system.

What Are the Main Causes of Electrical Fires?

The list of causes behind electrical fires is extensive, but some of the most common are:

• Improper use of cables or damage to them: In many buildings, cables are poorly organized and stored (some are stacked on top of each other or trapped under heavy machinery or stored items). This can cause overheating of the current, leading to a fire that affects the space and stored goods.
• Defective connections: A poor connection can create increased resistance, causing components such as switches to overheat (leading to problems due to high temperatures and overheating).
• Lack of maintenance: Dirt can also be a serious issue that causes accidents in many electrical installations. Dust in contact with moisture, for example, can cause short circuits and dangerous flames.

How to Prevent Electrical Fires?

To enhance safety in any building, it is essential to correctly design the electrical installation and invest time and resources in regular maintenance (periodically checking that all elements are in good condition, properly organized, and functioning correctly). This will ensure the installations are in optimal condition and significantly reduce threats.

Temperature Control Systems

Given the rapid nature of electrical fires and the damage they can cause, it is recommended to be as preventive as possible. How? By using temperature monitoring and control systems. These systems are designed to detect hot spots in the electrical installation and act before sparks or flames arise. Thermal cameras or infrared thermography can be used for this purpose.

Fire Detectors

Within any electrical fire protection plan, it is essential to have automatic detection systems that alert staff to any anomalies. Today, there are different types of detectors, but for these types of fires, we recommend high-sensitivity smoke or gas detectors, capable of alerting when the first signs of a fire appear.

Extinguishing Systems

Our fire plan should not only include detection but also systems that can control and extinguish these types of fires to reduce their impact and damage. But which one to use for electrical fires? For these types of fires, it’s best to avoid solutions that use water as an extinguishing agent (since water is electrically conductive, it could cause electrocution).

We recommend, instead, using gas or powder-based extinguishing systems when appropriate. Gaseous agents are non-conductive (avoiding sparks or other igniting phenomena), and they also produce less damage in the affected area (they are clean solutions that do not generate residues, so they don’t damage the tools and resources of an electrical installation).

Fire Sectorization

In addition to detection and extinguishing, it is also essential to have fire-resistant curtains and barriers to control smoke, which help contain the fire in the area where the flames originated and prevent its spread. This will protect the rest of the building, reduce damage to stored goods, and assist workers with evacuation.

With all this in mind, are you thinking about how to improve the safety of your installation against electrical fires? Whatever solution most appeals to you from those mentioned here, it is important to consider that every warehouse or building is unique and needs a personalized fire protection plan tailored to its needs. Therefore, we recommend conducting a preliminary study to understand the characteristics of your project and the risks it faces to create a complete, customized safety plan.

How to Extinguish Electrical Fires

Extinguishing electrical fires requires specific methods that ensure safety and effectiveness. Unlike other types of fires, electrical fires should not be addressed with water due to the risk of electrocution. It is essential to use techniques that cut off the energy source and neutralize the flames safely. Below are the most effective strategies for extinguishing electrical fires:

• Power Cutoff: The first step in addressing an electrical fire is to interrupt the power source. This could involve turning off switches or disconnecting electrical devices to stop the flow of electricity feeding the flames. Doing so reduces the risk of electrocution and limits fire spread. However, this step should only be performed if it is safe to do so, and no electrical equipment or cables should be touched directly during this process.
• Use of Class C Fire Extinguishers: Class C fire extinguishers are the most suitable for electrical fires. They are designed to extinguish fires involving energized electrical equipment. These contain agents such as carbon dioxide (CO2) or dry powder, which suppress flames by displacing oxygen or interrupting the chemical reaction maintaining the fire. These agents are non-conductive, making them safe to use in electrically risky environments.
• Carbon Dioxide (CO2): Carbon dioxide is a colorless gas that puts out fires by displacing oxygen in the air. Its use is effective for electrical fires because it leaves no residue and does not damage electronic equipment. However, it is essential to use it in well-ventilated areas to avoid the accumulation of CO2, which can be harmful to health.
• Dry Powder: Dry powder, typically made from ammonium phosphate, is another effective agent for extinguishing electrical fires. It works by interrupting the chemical reaction of the fire, suffocating the flames, and preventing re-ignition. Like CO2, it is non-conductive and safe to use on energized equipment. However, it may leave residues that require cleaning afterward.

With all this in mind, are you thinking about how to improve the safety of your installation against electrical fires? Whatever solution most appeals to you from those mentioned here, it is important to consider that every warehouse or building is unique and needs a personalized fire protection plan tailored to its needs. Therefore, we recommend conducting a preliminary study to understand the characteristics of your project and the risks it faces to create a complete, customized safety plan.