Workplace safety is a critical concern for anyone working around electrical equipment, and choosing the right protective gear can mean the difference between life and death. Can flame-resistant clothing protect against arc flash hazards?
Yes, properly rated flame-resistant (FR) clothing can protect against arc flash hazards when selected according to NFPA 70E standards and matched to the work environment’s specific arc flash hazard rating (measured in cal/cm²).
However, it’s important to continue reading because not all flame-resistant clothing protects against arc flash incidents. The specific rating of the FR clothing must match the potential arc flash exposure level, and workers need to understand the crucial differences between standard FR gear and arc-rated (AR) clothing.
What’s The Difference Between FR Clothing And Arc-Rated Clothing?
While all arc-rated (AR) is flame resistant clothing (FR), not all is arc-rated. FR clothing is designed to resist ignition and self-extinguish when exposed to fire. Still, it may not protect against the intense thermal energy released during an arc flash incident.
Arc-rated clothing undergoes additional testing specifically for arc flash protection. It’s tested to determine how much incident energy (measured in calories per square centimeter) it can block before the wearer receives second-degree burns. This rating is marked on AR garments, making it easier for workers to select appropriate protection for their hazard level.
How Do I Choose The Right Arc Rating For My Work Environment?
Selecting the proper AR clothing starts with a thorough arc flash hazard analysis of your workplace. This assessment determines the potential incident energy at various points in your electrical system, measured in cal/cm². Once you know these values, you can select AR clothing with ratings that exceed the potential exposure level.
For example, if your hazard analysis indicates a potential exposure of 8 cal/cm², you must wear AR clothing rated for at least 8 cal/cm². It’s common practice to add a margin of safety by selecting gear rated slightly higher than the calculated hazard.
What Happens If My FR Clothing Rating Is Too Low For An Arc Flash?
Wearing inadequately rated protective clothing during an arc flash incident can have severe consequences. If the incident energy exceeds the clothing’s protection rating, the intense heat can cause the garment to break open, allowing direct exposure to the arc flash energy.
This scenario can result in severe burns, as temperatures during an arc flash can reach up to 35,000°F. Additionally, under-rated clothing may ignite or melt, potentially causing even more severe injuries than if lighter-weight protective clothing had been worn. This underscores the importance of proper hazard assessment and matching AR clothing ratings to specific workplace hazards.
What Other PPE Is Needed Besides Arc-Rated Clothing?
Arc-rated clothing alone isn’t sufficient protection against arc flash hazards. A complete PPE ensemble typically includes AR face shields, hard hats, safety glasses, ear protection, and AR gloves. Each component is crucial in protecting different body parts from thermal energy, projectiles, and other arc flash dangers.
The specific combination of PPE required depends on the work’s hazard category, as defined by NFPA 70E standards. Higher hazard categories require more comprehensive protection, potentially including switching suits or full-body arc flash suits.
How Often Should Arc-Rated Clothing Be Replaced?
AR clothing doesn’t last forever and requires regular inspection and replacement to maintain its protective properties. While there’s no fixed expiration date, several factors can indicate when replacement is necessary.
Visible damage such as holes, tears, or worn areas compromises the clothing’s protective abilities and requires immediate replacement. Even without visible damage, frequent washing and wearing can gradually degrade the AR properties. Most manufacturers recommend replacing AR clothing when it shows signs of wear, becomes contaminated with flammable substances, or after approximately 50 industrial washings.
Regular inspection of AR clothing should include checking for fading, thin spots, contamination, and damaged closures. Following proper care instructions is also important, as improper washing or drying can reduce the garment’s protective properties and lifespan.
Taking Action to Protect Your Workplace
The first step toward ensuring proper arc flash protection is to conduct or update your workplace’s arc flash hazard analysis with a qualified electrical engineer. Once you have accurate hazard ratings for your specific work environments, you can confidently select appropriately rated AR clothing and complementary PPE to adequately protect your team’s electrical work tasks.
Lynn Martelli is an editor at Readability. She received her MFA in Creative Writing from Antioch University and has worked as an editor for over 10 years. Lynn has edited a wide variety of books, including fiction, non-fiction, memoirs, and more. In her free time, Lynn enjoys reading, writing, and spending time with her family and friends.
