What’s the Difference and Which Do You Need?

(The Complete Guide for Safety Managers, Industrial Buyers, and Workers)

When it comes to workplace protection in high-heat or ignition-risk environments, few questions cause more confusion than the difference between flame-resistant (FR) and flame-retardant (FRT) clothing. While the names sound similar, the protection they provide — and the situations where each is appropriate — are very different. Choosing the wrong type can expose workers to preventable burn injuries, non-compliance citations, and unnecessary risk.

This guide breaks down the science, standards, and practical applications behind FR vs. FRT apparel so you can confidently outfit your team with the right level of protection.

What Is Flame-Resistant (FR) Clothing?

Flame-resistant clothing is made from fibers that are inherently self-extinguishing and engineered for high-heat hazards.
The protective properties are permanently built into the fabric.

Characteristics of FR Clothing

• Self-extinguishes when exposed to flame

• Protection lasts for the life of the garment

• Fabrics char, thicken, and insulate when exposed to heat

• Approved for applications with arc flash or flash fire risks

Common FR Materials

• Nomex®

• Kevlar® blends

• Modacrylic blends

• FR cotton/nylon blends

Where FR Clothing Is Required

• Utilities & electrical

• Oil & gas

• Petrochemical

• Mining & smelting

• Industrial maintenance

• Chemical processing

• High-voltage and battery manufacturing

If arc flash or flash fire hazards exist, only certified FR PPE is acceptable.

What Is Flame-Retardant (FRT) Clothing?

Flame-retardant clothing is treated with chemicals that slow ignition and reduce flame spread.
The protection is not inherent — it’s added.

Characteristics of FRT Clothing

• Protection gradually decreases with washing

• Slows flame spread but does not fully self-extinguish

• Designed for low-heat, low-risk conditions

• More cost-effective for light-duty applications

Common FRT Materials

• Treated cotton

• Treated poly-cotton blends

• Standard fabrics treated with FR chemistry

Best Uses for FRT Clothing

• Low-intensity sparks

• Light hot work

• General industrial tasks

• Environments without arc flash or flash fire risks

FRT is a budget-friendly option but not suitable for high-hazard environments.

FR vs. FRT: Quick Comparison Chart

Safety Standards That Define FR vs. FRT

FR Clothing Must Meet:

• NFPA 70E (Arc Flash PPE Categories)

• NFPA 2112 (Flash Fire Standard)

• ASTM F1506 (FR workwear performance)

• CSA Z462 (Canada electrical safety standard)

These standards test:

• Arc Thermal Performance (ATPV)

• Heat Transfer Performance (HTP)

• After-flame time

• Shrinkage and durability

FRT Clothing May Only Meet:

• ASTM D6413 Flame Test
  This is not an FR certification — it only tests flame resistance for a few seconds.

Which One Should You Choose?

Choose FR if:

• You work with energized electrical equipment

• You work around flammable vapors, gases, or combustibles

• You’re in industries like oil/gas, utilities, petrochemicals

• OSHA or NFPA standards apply

Choose FRT if:

• You need basic protection from sparks

• Your environment has low heat exposure

• You need budget-friendly workwear

• No arc flash or flash fire is present

The Bottom Line

FR = Engineered protection for high-hazard environments
FRT = Treated protection for low-hazard environments

Understanding the difference ensures OSHA compliance and reduces burn injury risk, downtime, and liability.

FAQ Fire Resistant vs Fire Retardant 

What is the main difference between flame-resistant and flame-retardant clothing?

Flame-resistant clothing is made from inherently fire-resistant fibers that self-extinguish, while flame-retardant clothing is chemically treated to slow ignition but does not provide permanent protection.

Does flame-retardant clothing lose its protection over time?

Yes. FRT garments lose effectiveness through laundering, abrasion, UV exposure, and general wear, making them unsuitable for high-risk applications requiring permanent protection.

Is FRT clothing acceptable for electrical or arc flash environments?

No. Only certified flame-resistant clothing that meets NFPA 70E or ASTM F1506 is allowed for arc flash hazards. FRT clothing is not compliant for these tasks.

Does FR clothing last longer than FRT clothing?

Yes. FR protection is built into the fabric and lasts for the entire life of the garment, providing greater long-term durability and reliability.

How do I know which standard my job requires?

A hazard risk assessment will determine if you’re exposed to arc flash, flash fire, or combustible materials. If so, you must use certified FR clothing. FRT is only acceptable for low-heat, low-risk work.

Is flame-retardant clothing cheaper than flame-resistant clothing?

Yes. FRT clothing is less expensive up front, making it a cost-effective option for low-risk environments. However, FR clothing provides better long-term value in high-risk industries due to permanent protection.

Explore More FR & FRT Protection

• Shop Flame-Resistant Clothing → /flame-resistant-clothing

• Explore Hi-Vis FR Gear → /hi-vis-fr

• Browse Winter FR Gear → /fr-winter

• Learn More: Flash Fire Safety Standards → /flash-fire-protection