Introduction

When it comes to workplace safety, especially in industries prone to arc flashes and flash fires, the fabric you wear can be a silent accomplice to danger. While flame resistant (FR) clothing is designed to protect, everyday fabrics like cotton, polyester, poly/cotton blends, wool, nylon, silk, and acrylic can pose significant risks. Understanding these hazards is crucial for making informed choices about protective workwear. Let’s break down the dangers of common fabrics in fire-related workplace hazards and see why investing in FR garments is a life-saving decision.

The Flammability of Common Fabrics

Cotton: The Comfortably Combustible Culprit

Cotton is lightweight, breathable, and comfortable, making it one of the most common clothing materials. However, untreated cotton is also highly flammable. When exposed to an arc flash or flash fire, it ignites rapidly and continues burning, acting as fuel for the flames. Once ignited, it can be difficult to extinguish, causing severe burns before the wearer has a chance to react.

🔥 Danger Factor: High
🛡 Protection Tip: Only wear FR-treated cotton that meets NFPA 2112, NFPA 70E, and ASTM F1506 standards.

Risk Breakdown:

• Cotton burns quickly and sustains combustion.
• Provides no melt protection but still clings to skin when burning.
• Even heavy-weight cotton fabric offers little protection.

Contrast with FR Cotton:

• FR cotton is chemically treated to resist ignition and self-extinguish.
• It provides a similar comfort level but with life-saving benefits.

Polyester: The Melting Menace

Polyester is prized for its durability, wrinkle resistance, and moisture-wicking properties. However, in a high-heat environment, polyester doesn’t just burn—it melts. This melting action can cause fabric to fuse to the skin, leading to deep and painful burns. Polyester also has a tendency to drip when burning, causing additional injury.

🔥 Danger Factor: Very High
🛡 Protection Tip: Avoid regular polyester in hazardous workplaces. Instead , choose FR-rated synthetic blends.

Risk Breakdown:

• Polyester melts and sticks to skin before igniting.
• Produces toxic fumes when burned.
• Takes longer to catch fire but results in severe injuries when it does.

Contrast with FR Polyester Blends:

• Some FR polyester blends exist that resist ignition and melting.
• Proper FR treatments can prevent melting and enhance protection.

Poly/Cotton Blends: The Double-Edged Sword

Poly/cotton blends combine the comfort of cotton with the strength of polyester—but inherit both fabrics’ worst fire properties. These blends can:

• Ignite quickly like cotton.
• Melt and stick to skin like polyester.
• Burn longer than either fabric alone.

🔥 Danger Factor: Extreme
🛡 Protection Tip: FR-treated poly/cotton blends exist, but 100% inherently flame resistant fabrics are preferable.

Risk Breakdown:

• A dangerous combination of quick ignition and melting.
• Produces thick, harmful smoke.
• Commonly used in workwear, making it a hidden danger in high-risk jobs.

Wool: The Resistant but Not Invincible Fiber

Wool has natural flame resistant properties, meaning it requires higher temperatures to ignite and often self-extinguishes. However, it is still not completely fireproof. In a prolonged fire situation, wool will eventually burn and can smolder, producing hot embers that may cause burns over time.

🔥 Danger Factor: Moderate
🛡 Protection Tip: While wool is safer than cotton or synthetics, it is not a substitute for FR clothing.

Risk Breakdown:

• Slower ignition but can sustain smoldering.
• Heavy wool can provide some insulation but does not provide industrial FR protection.

Nylon: The Hidden Hazard

Nylon is a strong, lightweight, and water-resistant synthetic fabric used in workwear, outdoor gear, and athletic clothing. However, like polyester, nylon melts at high temperatures and can stick to skin, causing severe burns. It also decomposes at lower temperatures, meaning it can start breaking down even before ignition occurs.

🔥 Danger Factor: Very High
🛡 Protection Tip: Avoid nylon-based clothing in hazardous work environments unless it is specifically FR-rated.

Risk Breakdown:

• Extremely dangerous and should not be worn in an FR risk environment
• Especially risky because breaks down at low temperatures

 

Silk: The Surprising Risk

Silk is often associated with luxury, comfort, and breathability, but it has an unexpected downside when it comes to fire safety. While silk ignites more slowly than cotton, once it catches fire, it burns rapidly and can produce toxic fumes when exposed to high heat.

🔥 Danger Factor: High
🛡 Protection Tip: Silk is not suitable for industrial workplaces with fire hazards. Stick to FR-rated alternatives.

Risk Breakdown:

• A slow burn that escalates quickly to a roaring inferno.
• Produces toxic fumes.
• Dangerous on many levels and not appropriate as FR fabric.

 

Acrylic: The Flash Fire Disaster

Acrylic fabrics are commonly used for warm clothing like sweaters, gloves, and thermal wear. However, acrylic is one of the worst offenders in fire safety:

• Ignites quickly.
• Burns at a dangerously high temperature.
• Melts and sticks to the skin, causing third-degree burns.
• Produces thick, toxic smoke.

🔥 Danger Factor: Extreme
🛡 Protection Tip: Avoid acrylic in any high-risk work environment. Choose FR-rated wool or fleece instead.

Risk Breakdown:

• Ignites quickly and burns at high temperatures
• Produces toxic smoke.
• Melts and sticks to skin.
• One of the most dangerous fabric that can be worn in FR hazard environment.

 

Types of Flame Resistant (FR) Fabrics Used by Rasco FR

FR Cotton

FR-treated cotton is 100% natural cotton fabric chemically treated to resist ignition. While comfortable and breathable, the treatment can wear off over time (after the useful life of the garment), requiring proper care and maintenance.

✅ Good for general FR protection
❌ Less durable than inherent FR fabrics

FR 88/12 (88% Cotton / 12% Nylon)

This blend balances comfort, durability, and protection. The nylon adds strength and abrasion resistance, making it a popular choice for industrial workwear.

✅ Better durability than 100% FR cotton
❌ Still less durable then inherent FR fabrics

Inherent FR Fabrics: DH Air, Modacrylic Blends, and FR Polartec

Unlike treated fabrics, inherent FR fabrics are made with fibers that are naturally flame resistant and won’t wash out over time.

• DH Air: Lightweight and highly breathable, making it ideal for hot work environments.
• Modacrylic Blends: Soft, durable, and excellent for multi-hazard protection.
• FR Polartec: Provides insulation and moisture-wicking for cold-weather protection.

✅ Permanent FR protection
✅ Higher durability than treated FR fabrics
✅ Better comfort and breathability

❌ More expensive than treated FR fabrics

 

The Role of Safety Standards

To mitigate the risks associated with flash fires and arc flashes, several safety standards exist to guide flame resistant clothing selection:

• NFPA 2112: Specifies minimum requirements for flame resistant fabrics used in garments for protection against flash fires.
• NFPA 70E: Covers electrical safety in workplaces and outlines FR clothing requirements for arc flash hazards.
• ASTM F1506: Defines performance specifications for textiles used in FR clothing for electric arc and thermal protection.

Conclusion

While everyday fabrics offer comfort, durability, and style, they can become deadly hazards in environments where arc flashes or flash fires occur. While so much emphasis has been placed upon the importance of donning garments made with flame resistant fabrics, it is crucial to not lose sight of the great risk posed by non flame resistant fabrics to persons in FR hazard environments. Understanding the risks of common materials—cotton, polyester, poly/cotton blends, wool, nylon, silk, and acrylic—is the first step in choosing the right protective workwear.

🔥 If your job involves fire risks, wearing FR clothing is not an option—it’s a necessity. Stay safe. Stay protected. Wear Rasco FR.