ARC RATED VERSUS FLAME RESISTANT — DO YOU KNOW THE DIFFERENCE?

Knowing the difference between arc-rated clothing (AR) and flame-resistant clothing (FR) is more important than you might think. If you’re not aware of the difference, you might find yourself purchasing the wrong PPE for arc flash protection. Let’s clear up any confusion and ensure that you and your team have the proper PPE to comply with NFPA 70E and protect your workers from arc flash hazards.

Arc rated and flame resistant do not mean the same thing. All arc rated garments are flame resistant, but not all flame-resistant garments are arc rated. NFPA 70E requires PPE to be arc rated, so flame-resistant alone does not comply.

The key word here is rated. Arc rated means that it has been tested, and the testing has determined a level of protection in calories per square centimeter. If the PPE is arc rated, this value will be visible on the material used as PPE. In addition, this value should be proceeded by one of the following abbreviations: ATPV (Arc Thermal Performance Value) or EBT (Energy Breakopen Threshold). The value that is determined to be the lowest during testing will be the value preceding the calorie rating.

Compliant

Arc Rated Clothing stating calorie rating and ATPV along with standard ASTM F 1506

By requirement, all arc-rated clothing is required to be flame resistant before testing. If it is only flame-resistant, but not arc rated it is not tested and does not apply to any particular hazard; arc-rated clothing is tested and applies solely to the risk of arc flash hazards.

I have seen situations in which a maintenance department will use flame-resistant PPE and think they are compliant with NFPA 70E arc flash requirements, which is not the case. To simplify, follow the list below and you can rest assured that you have purchased the proper garments for arc flash protection.

Arc Flash PPE Purchasing Checklist

• Purchase from a trusted manufacturer.

• State that you want “arc-rated” PPE.

• Make sure the PPE has a rating in calories per square centimeter.

• Make sure the rating is reported as ATPV or EBT.

• Make sure the clothing meets the standard ASTM F 1506.

Non-compliant (when this is the only label.)

Standard 2112 is the Standard on Flame Resistant Garments for Protection of Industrial Personnel Against Flash Fire. This label does not indicate arc rating and does not refer to NFPA 70E Electrical Safety in the Workplace nor ASTM F 1506.

In conclusion, many vendors claim that their flame-resistant clothing meets the standards for arc flash protection. This can be a result of dishonest business practices or ignorance on the part of the sales agent. Insist that the clothing you purchase meets the above criteria, so you know you are purchasing arc-rated clothing.

Thank you for your time. Mitchell & Lindsey offers Arc Flash Risk Assessments and Electrical Safety Training. If we can be of service to you in these areas or if you have any questions about this article, please reach out to me at the email or phone number below.

Don’t forget to check out our other articles and videos at www.mitchellandlindsey.com/resources.

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Thank you and be safe!

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Bobby Lindsey – CESCP
Mitchell & Lindsey – President
M: (502) 836-4217
email: blindsey@mitchellandlindsey.com

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