An arc flash event is a dangerous situation occurring when electricity travels through the air to make contact with a conductor or the ground. Arc flashes release exceptionally high heat energy, pressure waves, blinding light, soundwaves, and toxic fumes. According to consulting and research firm CapSchell, Inc., approximately five to ten arc flash events occur in the United States every day.
A number of factors contribute to arc flashes. Dust, dropped tools, corrosion, and other factors can damage electrical equipment, redirecting electrical current away from its intended course. A common cause of arc flashes is human error, often occurring when employees fail to ensure equipment has been properly de-energized.
Because of the violence of arc flash events, employees caught in the blast radius are at risk of severe burns, puncture wounds from flying debris, blast pressure, sound blast, fires, and heat. Serious injury or death are not uncommon results of an arc flash, which can affect any employee in the blast radius.
To protect employees from injury, an arc flash safety checklist is vital. IEEE Standard 1584-2002 offers a detailed guide for performing arc flash hazard calculations. Below are the most important questions to ask about your facility’s arc flash safety procedures:
Are all operators / maintenance staff who work with electric equipment properly educated on arc flash hazards?
- Do all employees working with, on, or near electric equipment have access to appropriate personal protective equipment (PPE) to protect against an arc flash event?
- Do all employees operating or maintaining power systems have access to a current one-line diagram?
- Do written safety procedures and processed for working with energized equipment exist? If so, are employees following them?
- Is electrical equipment properly grounded? Is the ground system tested regularly?
- Is your electrical equipment properly labeled with the PPE you would need to wear and the boundary you would need to setup if opening the equipment live?
- Are your relay / fuse coordination studies less than five years old? Are relays calibrated to the studies’ recommended settings?
If the answer to any of these question is no, your arc flash safety protocols should be reviewed and corrected. Doing so protects your employees from harm while reducing your business’ risk of equipment damage, fires, lawsuits, and fines for non-compliance.