Arch FlashBy Brian E. Pitzer, PE

Arc flash accidents are a leading cause of lost production time, and even death, resulting from electrical burns, electrocution, fires, and explosions. Arc flashes can be caused by dust and impurities, corrosion, condensation of vapor and water dripping, accidental touching, dropped tools, improperly designed equipment, or improper work procedures. Some of the hazards resulting from an arc flash are severe burns from heat, molten metal projectiles, blast pressures throwing workers, and hearing loss from sound blast.

As an employer, you are required to provide a safe working environment and the necessary employee training to equip the employees with the knowledge to perform their tasks in as safe a manner as possible. But exactly what is required by code, and what level of protection and training should be implemented in your facility?

The National Electrical Code (NEC) has requirements for warning labels mounted on the electrical equipment, but does not address training involved for employee safety. Article 110.16 requires that all electrical equipment likely to require examination, adjustment, service, or maintenance, while energized, to be field or factory-marked to warn qualified persons of potential electric arc flash hazards. There is an informational note referring to NFPA 70E, however these notes are not part of the NEC, but only recommended practices.

The Occupational Safety and Health Administration (OSHA) does not specifically deal with arc flash hazards; however, it does address safeguards for personnel protection. Part 1910 has a general requirement for the employer to perform a hazard assessment of the workplace to verify the existence of hazards or potential hazards that would require the use of personal protective equipment (PPE). It also covers the requirements for each level of PPE.

The National Fire Protection Association (NFPA) created NFPA 70E to bridge the gap between the NEC and OSHA. NFPA 70E (Standard for Electrical Safety in the Workplace) includes arc flash hazard as a potential danger to workers near and around live exposed electrical parts and provides guidance on implementing appropriate safety procedures and arc flash calculations. However, it is not enforced by either the NEC or OSHA.

This brings us back to our initial question, what is required by code and what level of protection and training should be implemented in your facility? The minimum that is required by the NEC and OSHA is as follows:

  1. Warning labels on electrical equipment. This could be as simple as a label with the words “WARNING ARC FLASH HAZARD” on equipment rated below 1200 amps.
  2. Perform a hazard assessment of the workplace. Again, there is no requirement on how or to what level the assessment should be performed.
  3. Have personal protective equipment available to employees. Depending on how detailed the assessment is, the employee may not know what level of PPE they should be wearing.

Meeting these requirements will provide a safer work environment, however, the potential for injury from arc flash could still be present. This could still lead to loss of production, death, and/or litigation. Also, some insurance companies will require a much higher level of warning labels, hazard assessment, and training for the facility.

This is where NFPA 70E comes in. This standard includes detailed requirements for arc flash hazard assessment, warning labels, PPE levels, training, and regular maintenance and re-assessment. It allows either calculations or computing software to determine the level of arc flash risk. Arc flash warning labels are required to have detailed hazard levels or required PPE. Employees will know exactly what level of PPE they should be wearing from the arc flash labels and required training. NFPA 70E requires all the above information to be revised and updated upon regular maintenance and re-assessment of the existing or revised electrical system in the facility.

Arc flash events in the workplace can be dangerous, very costly and, potentially, deadly. As an employer, you could implement the minimum safety requirements and eliminate a small portion of the potential hazards, or you could apply and enforce the NFPA 70E standard in your facility and help to provide a high level of electrical safety in the workplace, reducing loss of production, death, and litigation due to arc flash events.

Have questions about arc flash or concerns about your facility? Contact Brian E. Pitzer, PE at 717.434.1550 or [email protected].

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One thought on “Electrical Safety in the Workplace

  1. Jason says:

    The head is the most vulnerable part of the body in case of an electiric arc accident and needs maximum protection. A hood with a double layer of 350 gsm 100% cotton flame retardant fabric using a wide viewing face shield with ATPV rating would be very ideal as part of the outfit. Otherwise, these are great tips you have here.

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