Hazardous energy sources: risks and safety measures

• Posted on 10 December 2024
• 0

In the workplace, hazardous energy sources such as electricity, pressurised fluids, potential energy, thermal energy and hazardous chemicals can pose significant risks. When these energy sources are unexpectedly released, they can cause serious injuries or even death. Therefore, it is crucial to carefully manage these energy sources and implement safety measures, both during work processes and maintenance activities.

What are hazardous energy sources?

Hazardous energy includes any energy source that poses a risk of injury or death to workers. Some sources, such as electricity, are easily recognizable, while others are less obvious and often overlooked. Therefore, it is crucial to identify and isolate all forms of hazardous energy to prevent accidents.

Primary energy vs residual energy

Controlling hazardous energy requires a good understanding of both primary and residual energy. Primary energy refers to the active source of energy needed to operate machinery or equipment, such as electricity, fuel, compressed air or hydraulic fluids. This energy is used directly to initiate a process.

Residual energy is the energy left behind in systems after the primary energy source is switched off. This could, for example, be the pressure in a hydraulic system or the electrical voltage in a circuit. It is crucial to safely isolate or discharge this residual energy because, even after shutdown, it can still be dangerous. Both energy sources must be carefully managed to avoid accidents during maintenance work.

Different hazardous energy sources

1. Electricity is one of the most common and dangerous sources of energy in the workplace. It can cause damage by powering moving machine parts or live electrical circuits. Exposure to voltages above 50 volts can lead to electrocution or serious burns.

2. Pressurised fluids Fluids and gases under high pressure, such as in pneumatic and hydraulic systems, pose a significant risk to workers. These substances are often transported to machines through pipes. Unexpected release of these pressurised substances can lead to explosions or serious injuries due to mechanical hazards or direct contact with the substances, which are often dangerously hot or chemically aggressive.

3. Potential energy is the energy that an object possesses because of its position or condition. An example is an object located at a height, such as a lifting device or machine part. If this object suddenly falls or starts moving, the stored energy can be released and cause serious injuries.

4. Thermal energy is another workplace risk, especially when materials such as hot oils, steam or gases come close to workers. Temperature rises above 50°C can cause burns, while freezing hazards arise when working with liquefied gases such as nitrogen. Proper cooling or safe disposal of these materials is essential to prevent injury.

5. Hazardous chemicals Chemicals, such as petrol, diesel, gas or acid batteries, are also a hazardous source of energy. These substances can be explosive, flammable or toxic. In many cases, these substances are handled or stored in machinery, which can lead to leaks or dangerous reactions if safeguards are not working properly. Handling hazardous chemicals requires strict safety protocols to prevent uncontrolled reactions or harmful exposure.

Case studies: Workplace hazards

Figures from the Labour Inspectorate show that between 50 and 70 people die from workplace accidents every year, with construction, industry and transport being the most dangerous sectors. These accidents are often caused by careless handling of machinery, dangerous substances or lack of safety measures. Moreover, many long-term illnesses, such as diseases caused by exposure to hazardous substances, are not always directly linked to working conditions but contribute to an increased risk of premature death.

An example of an incident is a hydraulic system accident where residual energy was not properly isolated. This led to a sudden pressure discharge that seriously injured a worker. Another common incident involves an electrical leak in a machine. In this, a worker accidentally touched an uninsulated cable, resulting in a fatal electrocution.

The importance of Lockout-Tagout (LOTO)

One of the most important procedures to prevent accidents involving hazardous energy sources is the Lockout-Tagout (LOTO) procedure. This involves disconnecting and isolating a machine's primary energy source before any maintenance work is carried out. This includes switching off machines, locking switches and placing warning labels to ensure the machine is not accidentally switched back on. The final step is also to test (tryout) whether the shutdown is actually complete. It is also very important that residual energy, such as hydraulic pressure or electrical voltage, is discharged or blocked.

Conclusion

The management of hazardous energy sources is crucial to ensure safety in the workplace. Workers should be aware of the different types of energy sources that may be present in their work environment and the risks they pose. By following strict safety measures, such as isolating energy sources and implementing the Lockout-Tagout procedure, common accidents can be prevented. Safety awareness and training contribute greatly to this.

Want to know more about the potential hazards of energy sources in your workplace? Then contact our specialists. They are ready to help you further!