Arc flashes are one of the most dangerous electrical hazards in the workplace. The damage to human health can be severe and permanent, from hearing loss to skin burns, and the sudden occurrence of an arc flash may even result in death. Employers will need to assess their facility for arc flash hazards and implement safety measures accordingly.
In addition to engineering and administrative controls, it is important to keep workers safe with personal protective equipment (PPE). Although PPE is considered the last line of defense, arc flashes occur unexpectedly and the consequences of a worker lacking PPE can be serious. When it comes to stocking your workplace with arc flash PPE, you will want to conduct an arc flash hazard analysis to get the right information (such as arc rating) for choosing garments and personal equipment. It should be noted that OSHA requires employers to provide PPE at no charge to employees.
When it comes to arc flash, the PPE used is based on the arc flash rating. Arc flash ratings constitute PPE categories, with Category 1 being the least harmful and Category 4 posing the highest risk and requires the most protective gear. Whatever the PPE category is, arc flash PPE will always include the following:
- Eye Protection: Arc flashes produce extremely bright flashes that can cause permanent damage to a worker’s sight or eyes. Therefore, eye protection is essential. Safety goggles are used for the first and second category, while safety goggles are required for Category 3 and 4.
- Hearing Protection: The sound of an arc flash explosion can be deafening with the potential to exceed 160 dB (for reference, a jet plane take off registers at 120 dB). Ear plugs are required by NFPA to be worn in all arc flash zones.
- Shirts/Pants: Any exposed skin must be covered. The heat and light emitted by an arc flash can destroy and skin and tissue. It can be extremely painful and may cause long-term chronic pain and scarring. No matter the category of PPE, all garments must be arc-rated, and arc-rated shirts and pants are required for all four categories. However, Category 2 calls for an arc-rated jacket, and both Category 3 and 4 include arc-rated suit jackets and pants.
- Foot/Hand Protection: Leather footwear (typically boots) is the standard for arc flash protection because of their nonconductive properties. The same goes for safety gloves, as leather gloves are used. When reaching the more dangerous levels however, arc-rated gloves are required.
- Head Protection: Head protection is used in addition to hearing and eye protection. Depending on the category, approved and required protection includes hard hats and arc-rated flash suit hoods.
- Face Protection: Included in exposed skin that must be covered is the face. If an arc-rated flash hood or other protection does not already include face protection, workers are required to wear an arc-rated face shield or an arc-rated balaclava.