Arc Flash 101: Causes, Preventions, & OSHA Standards

As defined by the Electrical Safety Forum, arc flashes are dangerous electrical events that occur when an electric current jumps across the gap between two conductors, creating an electrical arc. Arc flashes can reach temperatures up to 35,000°F and, contrary to popular belief, are not rare incidents. In fact, over 30,000 arc flash accidents occur annually, resulting in more than 400 fatalities a year in the U.S. alone.

Causes

The easiest way to prevent these accidents from occurring is to be aware of their causes.

  • Most commonly, arc flashes are a result of human error. Accidentally touching a live conductor, dropping a tool onto exposed electrical parts, and overloading (due to improperly installed and maintained machinery) are the top causes of arc flashes.

  • However, other environmental factors such as dust, moisture, and corrosion can increase the risk of an explosion.

  • Accidents can also occur due to aging electrical equipment like switches, circuit breakers, and transformers, which can deteriorate over time.

Preventions

Although some causes of arc flashes are out of human control, there are many measures that can be taken to prevent accidents from occurring such as, for example, conducting a hazard analysis.

  • Before starting work on electrical equipment, take a look at the environment and identify potential hazards.

  • While working with electrical equipment, be sure to always wear proper personal protective equipment (PPE). This includes flame-resistant clothing, insulating gloves, eye and ear protection, and more.

  • Never skip steps, and always follow proper Lockout/Tagout procedures, which are used to de-energize and secure machinery, helping prevent the unexpected startup or release of stored energy.

  • Also, regularly maintaining and testing electrical equipment prior to use can help identify potential risks before they can lead to accidents.

OSHA Standards & Electrical Safety

Occupational Health and Safety Administration (OSHA) adopted the 1968 edition of the National Electrical Code (NEC) and, later, the 1971 edition. However, the NEC was not sufficient for workplace safety, and OSHA endorsed an NFPA proposal to develop an electrical safety standard compatible with the OSHA requirements; this became the NFPA 70E. NFPA became the basis for OSHA’s General Industry Electrical Safety Standards which included general performance criteria. The current edition of NFPA 70E is used by OSHA to flesh out OSHA’s general performance requirements by establishing standard industry practices

OSHA Standards are what must be done, and NFPA 70E covers how.

  • The general Duty Clause – requires workplaces to be free from recognized hazards

  • Employees are required to comply with rules pursuant to the act

  • The specific Duty Clause- requires the employer to comply with OSHA standards

Understanding and abiding by electrical safety can be the difference between life and death. Following proper electrical safety standards helps reduce shock and arc flash exposure, prevents injury and fatalities, and lowers liability and insurance costs.

Accidents happen but most can be prevented with proper knowledge and training. Is your workplace prepared to protect employees from accidents? Contact us at info@pearsonsafety.com to find out how you can ensure your company is compliant and employees are safe from electrical hazards.

Eric Hughes