What is an Arc Flash?
As defined by OSHA an Arc Flash is “a phenomenon where a flashover of electric current leaves its intended path and travels through the air from one conductor to another, or to the ground. The results are often violent and when a human is in close proximity to the arc flash, serious injury and even death can occur”.
Simply put, and Arc Flash is a powerful electrical explosion with potentially deadly consequences. Arc Flashes can produces temperatures in excess of 35,000º Fahrenheit, almost four times the temperature of the surface of the sun.
The ramifications from an Arc Flash are numerous, here is some of the data illustrating the severity of Arc Flash incidents:
- Over 2,000 workers annually are treated for Arc Flash injuries;
- Arc Flash incidents cost companies millions in medical bills, downtime, and litigation;
- 80% of electrical injuries are caused by Arc Flash events versus electrocutions;
- Arc Flash explosions can vaporize copper conductors and will expand them to 67,000 times their original volume when the solid copper vaporizes.
What Causes an Arc Flash?
Some arcs are caused by human error including dropped tools, accidental contact with electrical systems, and improper work procedures. Another common cause of an arc is insulation failure. Build-up of dust, contamination, and corrosion on insulating surfaces can provide a path for current flow. Sparks created during racking of breakers, replacement of fuses, and closing into faulted lines can also produce an arc. Birds, rodents, and other animals can inadvertently bridge the space between conductors or cause leads to slap together, creating an arcing fault.
What are the Requirements for Arc Flash Assessments?
OSHA requires that employers identify electrical hazards (including Arc Flash) and protect their workers for these hazards. However, OSHA does not stipulate how to meet this mandate. This is where The National Fire Protection Association (NFPA) steps in to provide the guidance on HOW to keep workers safe, with their code NFPA 70E.
Below we list an overview of the codes that impact Arc Flash for employers:
OSHA Standard 29-CFR, Part 1910, Subpart S – Addresses the need for employers “Standards for Work Practices” and references NFPA 70E. This standard also discusses Personal Protective Equipment (PPE) that must be worn around electrical hazards, and the requirements of employers to assess work place hazards, such as Arc Flashes.
NFPA 70E – This codes outlines how the Arc Flash Assessment should be performed, including how to determine if the arch flash hazard exist, what are the arc flash boundaries, what is the appropriate PPE to don given the boundaries, methods to protect workers in the event of an Arc Flash incident, and how to properly label Arc Flash hazards to alert workers of the hazards and proper boundaries.
How Hughes will Help you with Arc Flash Compliance
- Data Collection: We go each location in your facility that could provide a thermal energy incident and collect data to allow us to develop your customized plan.
- Incident Energy Calculations: Incident Energy tells you the levels or risk in your electrical panels (NFPA 70E requirement)
- Coordination Study & Mitigation: Reduce risk by lowering the incident energy and Hazard Risk Category. This lowers the PPE requirements.
- Arc Flash Field Labeling: In Compliance with OSHA and NFPA 70E, Field Labels will be installed that include incident energy calculations.
- Arc Flash & Electrical Safety Training: Learn how to work safely in your facility’s electrical environment.
Contact Hughes Environmental Today to receive a quote on an Arc Flash Assessment