The Shocking Truth: Safely Navigating the Arc Flash Hazard
Arc flashes are responsible for 400 deaths per year on average, and they’re more common than you think. Even though they’re not 100% preventable, there are ways to avoid and protect against them.
Arc Flash is an explosion caused by energized electrical equipment. An arc flash occurs when an electrical current leaves its path and connects with the air, ground, or another phase in an electrical system. Arc flashes are extremely hazardous and can result in serious injury or even death. They have been known to reach temperatures as high as 35,000° Fahrenheit, which is 4 times hotter than the sun!
In buildings such as hospitals where the system is powering critical medical equipment and cannot be shut down, performing maintenance while the system is energized is unavoidable. In that case, arc-rated Personal Protective Equipment (PPE) must be worn. An Arc Flash Study can be performed to calculate the incident energy at every point on the equipment. This will determine the level of PPE that should be worn.
There are 4 different categories to classify the different levels of arc flash hazards and their required PPE. Category 1 and 2 typically only require one layer of PPE, such as arc-rated long-sleeve shirts and pants, face shield and mask, hard hat, and jacket. Category 3 and 4 are more hazardous and require additional arc-rated protection such as an arc-flash suit jacket and hood.
The only way to prevent an Arc Flash entirely is to avoid performing maintenance on energized equipment. In the case maintenance is required, it is important that the correct PPE is worn to avoid fatal injuries.
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