ARC Rating for FR Clothing: A Complete Guide

An arc rating for FR clothing tells you about a garment’s level of protection is a must in hazardous work environments. If arc-resistant, flame-resistant work clothes are a required part of your workwear, you need to ensure that every garment you buy provides adequate protection against arc flash risks you may encounter on the job.

FR clothing arc ratings seem complicated on the surface, but once you understand what CAT ratings are and what arc ratings mean, you’ll come away with a clear understanding of the type of protection you need to meet FR clothing safety and compliance standards and how you can ensure your safety at work.

What Is an Arc Rating for FR Clothing?

The arc rating for FR clothing indicates how much protection a garment offers in the event of an arc flash. An arc flash may be a sudden, powerful electrical discharge or explosion as electrical current travels through air to the ground or another conductor. Arc flashes superheat the air to temperatures near 20,000°C (35,000°F) and can cause serious burns, injuries, or death without proper protection. Arc-rated FR clothing is one effective form of protection in the event of an arc flash. When the proper arc-rated, flame-resistant work clothes are worn, the risk of extensive second-degree burns is minimized. FR clothing arc ratings are a simple way to see the protection level of different workwear garments at a glance.

FR Clothing Arc Ratings

What is the CAT rating on FR clothing? The CAT (PPE Category) rating details how much energy, in calories per square centimeter, a garment can withstand from an arc flash before serious second-degree burns occur. Higher-risk occupations and worksites require clothing with higher CAT ratings for better insulation from potential burns in the event of an arc flash.

In a nutshell, the CAT tells you a garment’s minimum Arc Thermal Performance Value (ATPV). The ATPV is written as a number of calories per square centimeter, showing how much energy (in calories) of an arc flash every square centimeter of an item of clothing can handle before melting/burning and resulting in a 50% probability of a second-degree burn. All quality arc-rated clothing is run through a battery of tests to ensure it meets or exceeds standards.

PPE Category (CAT) Level

Minimum Arc Rating


4.0 cal/cm2


8.0 cal/cm2


25 cal/cm2


40 cal/cm2

These ratings show the minimum level of protection for each category. Each category could provide up to the next category’s ATPV; CAT 1 could provide up to 8 calories per square centimeter but must provide a minimum of 4 cal/cm2.

We've looked at arc ratings, but what are FR ratings? FR ratings for clothing are simply the garments’ PPE categories (CAT), assigned a level of 1-4 according to their ATPV. These ratings show how much protection a garment offers, ranging from a minimum of 4 (CAT 1) to 40 (CAT 4) calories per square centimeter. Usually, arc-rated FR clothing must be a minimum CAT 2 to ensure compliance. With this in mind, is all FR clothing arc-rated? No. While all arc-rated clothing is also flame-resistant, flame-resistant clothing isn’t necessarily arc-rated. Look for special labels and product details that verify a garment is arc-rated before wearing it in any setting where arc flash is a potential risk.

Choosing the Right Arc-Rated Apparel

Whether you’re looking for women’s or men’s flame-resistant clothing, more layers to add to your workwear wardrobe, or arc-rated accessories that provide head-to-toe protection, the #1 consideration is choosing a quality apparel brand. MWG Apparel is your one-stop shop for arc-rated FR workwear, from base layers and accessories to coveralls and shirts. We offer a full range of women’s and men’s flame-resistant clothing options from CAT 1-4 to ensure protection in any work environment.

You’ll find CAT 1 base layers (long-sleeve shirts, long johns, t-shirts, and undergarments), CAT 2 shirts, utility pants, coveralls, vests, and overalls, CAT 3 hoodies, lined utility pants, lined overalls, and accessories, and CAT 4 insulated overalls, coveralls, and jackets in our MWG collections to meet or exceed your workplace safety standards. All MWG Apparel is vigorously third-party tested by Aitex, the industry leader in product testing, to make sure every garment we produce can stand up to the most dangerous workplace hazards.

Get the highest quality FR workwear from MWG Apparel. Shop our array of products from outerwear to base layers, ensuring complete protection from head to toe.
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