In case you don’t know the term, an arc flash is an electrical arc, occurring between two electrical devices, that is sustained by nothing but air. When an arc flash occurs, there is a burst of light, the temperature at the center of the event soars to nearly 35,000 °F, and the arc itself can grow to gigantic proportions in just milliseconds.
As bad as an arc flash is, an arc blast is even worse. Here, along with the flash, the devices where the event occurred blow up, throwing molten metal and shrapnel in all directions at the speed of a rifle bullet.
Both events are extremely dangerous and destructive. Typically, the potential for these to occur—and the hazard they pose if they do—are mitigated through arc flash hazard analysis. This article answers some of the basic questions often asked regarding arc flash hazard analysis.
Q: What does arc flash hazard analysis involve?
A: Good arc flash hazard analysis involves collecting the electrical system’s equipment data, performing three types of studies—short circuit, protective device coordination, and arc flash analysis—and issuing a final study report that contains recommendations for mitigating potential arc flash hazards within the system.
Other related services include:
- Preparing equipment safety labels
- Producing an updated single-line diagram of the electrical system
- Recommending the proper PPE (personal protective equipment)
- Conducting NFPA 70E electrical safety training
Q: It sounds like a big hassle. Why should I bother with arc flash hazard analysis?
A: To protect the lives and health of the personnel who work near your electrical distribution equipment. Every year, more than 2,000 people are admitted to hospital burn units for thermal burns from arcing accidents. Such accidents also result in over one job-related fatality per day, on average. Most victims were unprepared for the hazards they faced.
Arc flash hazard analysis won’t eliminate the possibility of arcing accidents occurring, but it can mitigate the danger and equip your personnel with the resources they need to work safely on or around your electrical system equipment.
Q: Arc flash hazard analysis sounds expensive. How do I justify the cost?
A: By comparing this cost to that of an arc flash accident. Statistics show an arc flash accident can cost a company $1 million or more in lost production, equipment replacement and repair, lawsuits, increased insurance premiums, and regulatory fines. Then, there is the emotional cost of the damage to the company’s reputation as a result of all the bad publicity.
Because it is a labor-intensive process that requires specific technical expertise, arc flash hazard analysis does cost money. But arc flash hazard analysis is also an inexpensive form of risk management that helps protect against the high costs often associated with arc flash accidents.
Q: Our equipment has been installed according to the National Electrical Code. Doesn’t that mean it is safe to work around?
A: The standards in the NEC apply to equipment operating in its normal working condition. Electrical maintenance technicians work on equipment in its abnormal condition: when it is damaged or needing maintenance. It is during these times when arcing accidents are most likely to occur.
The potential for these accidents to occur and their severity are why OSHA asked the National Fire Protection Association (NFPA) to address the safety of workers exposed to electrical hazards. NFPA 70E Standard for Electrical Safety in the Workplace mandates that arc flash hazard analysis be performed before workers unknowingly expose themselves to potentially lethal electrical hazards.
Q: Arc flash hazard analysis isn’t required by law, is it?
A: It’s true that OSHA’s regulations do not require a company to have a formal arc flash hazard analysis program. NFPA 70E is a consensus standard, not the law. But it is also true that OSHA can and does levy fines against companies that ignore NFPA 70E safety standards.
OSHA requires employers to provide workplaces “free from recognized hazards that are causing or likely to cause death or serious physical harm” to employees (OSHA General Duty clause). Specifically, 29 CFR §1910.333 of OSHA’s General Industry Standards mandates “Safety-related work practices shall be employed to prevent electric shock or other injuries resulting from either direct or indirect electrical contacts, when work is performed on or near equipment or circuits.”
The OSHA standard also mandates installing equipment safety labels on electrical equipment to identify the hazard levels electrical personnel face when working on or around these devices.
Think of it this way: OSHA’s requirements are the law; NFPA 70E is the industry standard, the rulebook OSHA uses to determine if a company is within the law.
Hopefully, this brief Q&A session has answered your most basic questions about arc flash hazard analysis and its importance to electrical safety. For more on the benefits of arc flash hazard analysis for your organization, please contact Dan Steiner.