CAT 1 vs. CAT 2 FR Clothing: What Is the Difference?

CAT 1 and CAT 2 are arc-flash PPE categories used to help select protective clothing for certain electrical tasks. The most visible difference is the minimum arc rating:

• CAT 1 clothing requires a minimum arc rating of 4 cal/cm².
• CAT 2 clothing requires a minimum arc rating of 8 cal/cm².

That does not mean CAT 2 is the correct choice for every electrical job. The required protection must come from the arc-flash risk assessment and the employer’s electrical safety program. When the PPE category method applies, the task and equipment conditions determine the category. When the incident-energy method is used, clothing is selected by its arc rating rather than by converting the result into a CAT number. Clothing should never be selected by guessing from voltage, job title, or equipment type alone.

CAT 1 vs. CAT 2 FR Clothing: Key Differences

Both categories require arc-rated clothing. A garment labeled only as flame resistant, without an arc rating, is not enough.

Comparison	CAT 1	CAT 2
Minimum clothing arc rating	4 cal/cm²	8 cal/cm²
Typical clothing	Arc-rated long-sleeve shirt and pants or arc-rated coverall	Arc-rated long-sleeve shirt and pants or arc-rated coverall
Head and face protection	Arc-rated face protection as required by the applicable PPE table and task	Commonly requires an arc-rated face shield with an arc-rated balaclava, or an arc-flash suit hood
Other PPE	Hard hat, safety glasses or goggles, hearing protection, gloves and footwear as required	Similar supporting PPE, with protection selected for the higher category
Weight and comfort	Often lighter, depending on the fabric and garment	May be heavier, although lightweight CAT 2 fabrics are available
Selection basis	Tasks assigned to CAT 1 under the applicable category method	Tasks assigned to CAT 2 under the applicable category method

The category applies to the complete PPE selection, not just the shirt. Face, head, hand, hearing, and foot protection must also match the task and the safety procedure being followed.

The minimum ratings are thresholds. A CAT 1 garment may have an arc rating higher than 4 cal/cm², and a CAT 2 garment may be rated above 8 cal/cm². The exact rating should always be checked on the label.

How to Choose Between CAT 1 and CAT 2 FR Clothing

Check the Arc-Flash Risk Assessment

Start by confirming whether the task has an arc-flash hazard. The assessment should consider the equipment, equipment condition, available fault current, fault-clearing time, working distance, and the work being performed.

Its purpose is to determine the protective measures required for that particular exposure. It is not safe to assume that all work on the same voltage needs the same category of clothing.

Whenever possible, equipment should be placed in an electrically safe work condition before work begins. PPE is an important last line of defense, but it does not replace de-energization, lockout/tagout, equipment maintenance, or safe work practices.

Check How Your Required Protection Is Determined

Arc-flash protection may be selected through an incident-energy analysis or through an applicable PPE category method. These approaches should not be mixed.

With the incident-energy method, clothing is selected by comparing its arc rating with the expected incident energy at the stated working distance. The clothing system must have an arc rating at least equal to that exposure.

With the category method, the equipment and task must fall within the specified limits of the relevant table. The assigned category then determines the minimum arc rating and the other required PPE.

CAT 1 and CAT 2 are therefore not general descriptions of “low-risk” and “medium-risk” electrical work. They are parts of a structured selection process.

Consider Everything You Will Be Wearing

An arc-rated shirt is only one part of the system. Pants, coveralls, jackets, rainwear, reflective garments, gloves, face protection, and head protection can all affect overall performance.

Outer layers exposed to the hazard must provide the required protection. Underlayers must not create an additional melting or ignition hazard. If several arc-rated garments are intended to work together, use the tested system rating rather than adding their individual ratings together.

Once the full PPE requirements have been identified, you can determine whether a CAT 1 or CAT 2 shirt is suitable as the everyday base garment.

CAT 1 and CAT 2 Shirts for Everyday Work

When a CAT 1 Shirt May Be Suitable

A CAT 1 shirt may be suitable when the approved PPE category method assigns the task to Category 1 and the rest of the required protective equipment is also worn.

The shirt must carry an arc rating of at least 4 cal/cm². Fit, sleeve coverage, closures, and compatibility with the worker’s pants and other PPE still need to be checked.

CAT 1 should not be chosen merely because the task appears brief or routine. A short task can still involve substantial incident energy, while a longer task may present a different level of exposure. The assessment—not task duration alone—determines the protection.

When a CAT 2 Shirt May Be Suitable

A CAT 2 shirt must have an arc rating of at least 8 cal/cm². CAT 2 is commonly used for electrical workers whose approved task and equipment conditions fall within that category.

Many arc-rated FR shirts are designed for CAT 2 daily wear, allowing workers to use one protective base garment across multiple tasks covered by the employer’s program. Even then, the shirt does not automatically provide the complete PPE required for every CAT 2 task.

Check the garment’s actual arc rating instead of relying only on the category printed in a product title. Two CAT 2 shirts can have different ratings, fabrics, weights, fits, and comfort characteristics.

When You Need More Than an Arc-Rated Shirt

Neither CAT 1 nor CAT 2 means “shirt only.”

Depending on the assigned category and task, workers may also need arc-rated pants or coveralls, an arc-rated face shield, a balaclava or hood, a hard hat, safety glasses, hearing protection, gloves, and suitable footwear.

An arc-rated shirt also cannot protect skin left exposed by rolled sleeves, an open front, or a shirt that pulls out of position while the wearer reaches or bends. The complete system must provide the required coverage throughout the job.

What to Check Before Buying CAT-Rated FR Clothing

Check the Arc Rating on the Label

Look for the arc rating in cal/cm² on the garment label. Do not rely solely on descriptions such as “FR,” “electrical work shirt,” or “CAT-rated fabric.”

The label should allow the purchaser and wearer to identify the protective rating and applicable standards. If the claimed category cannot be supported by a visible arc rating, ask the supplier for the relevant product and testing information.

Look for the Right Safety Standards

ASTM F1506 establishes performance and labeling requirements for flame-resistant and arc-rated clothing worn by workers exposed to flames and electrical arcs. ASTM F1959/F1959M is used to determine the arc rating of clothing materials.

NFPA 70E provides a framework for workplace electrical safety and PPE selection, but NFPA does not approve individual garments. Claims such as “NFPA 70E certified” should not replace a review of the label, arc rating, applicable ASTM standards, and manufacturer documentation.

General FR clothing requirements may also differ by hazard and industry. A garment suitable for an electrical arc exposure is not automatically the correct choice for every flash-fire, welding, chemical, or visibility hazard.

Check Fit, Coverage, and Comfort

The shirt should provide enough room for movement without becoming excessively loose around machinery. Sleeves should remain down, the front should close properly, and the shirt tail should maintain coverage during normal work.

Fabric weight alone does not determine the category. A well-designed lightweight fabric may reach CAT 2, while a heavier garment may have a different rating. For regular wear, breathability, moisture management, seam placement, and range of motion can affect whether employees wear the clothing correctly for an entire shift.

Review Care Instructions and Expected Service Life

Arc-rated clothing should be washed, dried, repaired, and stored according to the manufacturer’s instructions. Contamination with flammable substances, damaged closures, holes, severe abrasion, or unauthorized alterations may make the garment unsuitable for service.

There is no universal retirement date for every CAT-rated garment. Its usable life depends on construction, wear, laundering, contamination, damage, and the employer’s inspection program.

Conclusion

The main difference between CAT 1 and CAT 2 is straightforward: CAT 1 requires a minimum arc rating of 4 cal/cm², while CAT 2 requires at least 8 cal/cm².

Choosing between them is not simply a matter of buying the higher number. Confirm how the task was assessed, follow the approved selection method, and check every part of the required PPE system. The right clothing is the clothing that meets the documented hazard and can be worn correctly throughout the work.

FAQ

Does CAT-Rated Clothing Protect Against Electric Shock?

No. CAT-rated clothing helps protect against the thermal effects of an arc flash. It does not insulate the wearer from electrical contact. Shock protection may require voltage-rated gloves, insulating equipment, boundaries, and other controls.

Can Logos or Reflective Tape Affect Arc Protection?

Yes. Added logos, patches, transfers, reflective tape, and repair materials can affect the garment’s performance. Decorations and alterations should be approved for the intended hazard and applied according to the garment manufacturer’s instructions.

Is High-Visibility CAT-Rated Clothing Automatically ANSI/ISEA 107 Compliant?

No. Arc rating and high-visibility compliance address different hazards. A garment may be CAT rated without meeting ANSI/ISEA 107, or it may meet visibility requirements without having an arc rating. Both properties must be verified separately when both are required.

What Should You Do With Clothing After an Arc-Flash Exposure?

Remove it from service immediately. Do not continue wearing or laundering it for reuse without a qualified evaluation. Follow the employer’s incident procedures and the manufacturer’s guidance to determine whether it must be replaced.