Arc flash incidents can be deadly, so workers must take the appropriate precautions to ensure their safety on the job. Workers must understand arc flash categories so they can avoid electrical injuries that cause severe burns, hospitalization, and even fatalities. We’ll explain arc flash categories and what they mean in hopes of providing information that could save your life or the lives of your crew mates.
What Is an Arc Flash?
An arc flash is a sudden release of electrical energy that occurs from a fault in an electrical system. It could be due to a missing panel cover or screw or bolt inside machinery that wasn’t tight enough. The four arc flash categories relate to the arc thermal protection value (ATPV) and the type of personal protective equipment (PPE) workers should wear.
Category 1 (ATPV of 4 or lower cal/cm2)
This level is for equipment that requires basic PPE: eye protection, hearing protection, gloves, and clothing, such as non-melting, natural fibered, or untreated cotton.
Category 2 (ATPV of 8 or lower cal/cm2)
This level requires greater protection than category 1 due to increased chances of exposure to high currents. Workers can protect themselves by wearing daily PPE, including leather gloves, FR-rated clothing, and safety glasses or goggles. Fire-retardant jumpsuits are great garments because they cover most of the body.
Category 3 (ATPV of 25 or lower cal/cm2)
For this category, all clothing and equipment must meet the requirements of Categories 1 and 2. Furthermore, PPE must include a face shield, arc-rated balaclava, and insulation for added protection.
Category 4 (ATPV of 40 or lower cal/cm2)
Category 4 is the highest and most severe when it comes to arc-flash ratings. PPE for this category includes all clothing and equipment from Categories 1–3. Additionally, workers must wear protective shields, double-layer switching coats or jackets, and hard hats.
Communication Is the Key to a Safe Workplace
Electrical safety is a crucial aspect of any work environment that involves electric systems. It’s important to understand the hazards and know what PPE category to wear in situations where arc flashes may occur. Understanding arc flash categories and what they mean and being prepared in the event of an accident is crucial for preventing injuries and fatalities. If necessary, consult your employer to make sure your team members have all the electrical gear they need.