Arc Flash and Arc Blast Hazards: What they are and how to prevent them

When it comes to electrical safety, two terms often arise: Arc Flash and Arc Blast. Both occurrences pose serious risks to personnel working with or near electrical equipment.

With the first ever national Arc Flash Awareness Day coming up (organised by ProGARM), we want to explore the meaning of Arc Flash and Arc Blast, the potential dangers they pose, and essential measures to prevent them and to maintain a safe working environment to make sure that everyone gets to go home safe at the end of the day.

Arc Flash vs. Arc Blast

An Arc Flash is a sudden and intense release of energy caused by an electrical fault or short circuit. This release results in an arc fault, characterised by a rapid, luminous discharge of electrical energy. Arc flashes can reach temperatures hotter than the surface of the sun, causing severe burns, fires, and damage to equipment.

An arc blast is the explosive release of energy that accompanies an arc flash. It occurs when the intense heat from the arc flash vapourises surrounding materials, creating a pressure wave that can propel debris and cause significant damage to equipment and personnel. Arc blasts pose additional risks, including concussions, hearing damage, and blunt force trauma.

Understanding the Risks

Both Arc Flash and Arc Blast can cause severe damage to personnel and even result in fatalities.

Although there is no data on the number of injuries caused specifically by Arc Flash or Blast in the UK, HSE reports around 1000 electrical accidents happening every year with 30 resulting in death. ProGARM’s own research* revealed that 57% of electrical workers had first-hand experience of an Arc Flash incident, having experienced or seen someone else suffer a strike during their career. This suggests the frequency of Arc Flash incidents is far higher than officially reported electrical incident statistics might suggest.

This is why understanding the potential risks associated with Arc Flash and Blast is the first step to creating a safer working environment.

Some of the primary risks include:

  • Thermal Burns: The high temperatures generated by an arc flash can cause severe burns to anyone in close proximity, leading to serious physical injuries.
  • Impact Injuries: The powerful arc blast can propel debris and shrapnel at high speeds, causing severe lacerations, fractures, and penetrating injuries.
  • Pressure Wave Injuries: The sudden release of energy creates a pressure wave that can throw individuals off balance, cause concussions, or even collapse structures.
  • Hearing Loss: The loud noise accompanying an arc blast can cause permanent hearing damage to those nearby.

Prevention and Safety Measures

Preventing accidents involving Arc Flash and Blast is a combination of careful planning, training, and adherence to safety standards. Here are some essential measures to minimise the risks:

Conducting a Risk Assessment: There is a legal requirement under the Management of Health and Safety at Work Regulations to identify potential Arc Flash hazards by performing a thorough evaluation of electrical systems, equipment, and work practices.

Implementing Safety Procedures: Develop and enforce strict safety procedures, including lockout/tagout, or other isolation protocols to ensure electrical equipment is safely de-energised before any maintenance or repair work.

Personal Protective Equipment (PPE): Provide appropriate PPE to employees working with or around electrical systems. This includes flame-resistant clothing, face shields, safety glasses, gloves, and hearing protection. We recommend that you check out ProGARM for a wide range of Arc Flash and Flame Resistant protective garments

Equipment Maintenance: Regularly inspect and maintain electrical equipment to ensure it is in good working condition. Properly trained personnel should handle repairs or replacements.

Training and Education: Conduct thorough training programmes for employees to educate them about Arc Flash hazards, safe work practices, and emergency response procedures. Regular refresher courses are crucial to keeping knowledge up to date. Most of our courses include modules on the topic of Arc Flash and Blast.

Warning Signage: Clearly label electrical equipment with warning signs indicating potential arc flash hazards. These signs should indicate the required PPE precautions and approach distances.

Electrical System Design: Work with qualified electrical engineers to design and install electrical systems that minimise Arc Flash risks. Consider implementing advanced protection mechanisms, such as arc-resistant switchgear, to reduce the potential impact of an Arc Flash, or maintenance settings on electrical protection schemes to clear faults more quickly in the event of a fault developing.

Emergency Preparedness: Develop and practice emergency response plans that address Arc Blast incidents. Ensure employees know how to evacuate the area and how to administer first aid if injuries occur.

Arc Flash Awareness Day 2024

Arc Flash Awareness Day is a focal point for everyone involved with work where arc flash is a risk. The day has been created to drive awareness of the risks of arc flash incidents, and to share best practice on how to avoid and mitigate those risks so that organisations can create safer work environments and protect their employees from harm.

To learn more, join ProGARM on 7th of June 2024 for a series of webinars for Arc Flash Awareness Day 2024.