Combustible Dust Series: Part 4 – Is FR Clothing Needed for a Combustible Dust Hazard?

In Part 3 of this series, we learned about the specified methods to mitigate combustible dust hazards, including building design, equipment design, controlling ignition sources, and dust control measures. But what happens if, despite all mitigation efforts, a combustible dust flash fire or explosion occurs? What is the last line of defense to safeguard workers? Tyndale’s Vice President of Corporate Strategy and Technical, Scott Margolin, explains why flame resistant (FR) clothing is required whenever a flash fire hazard has been identified.

The short answer is “yes, you need to wear FR clothing if exposed to a potential combustible dust hazard” and Scott explains why. Since combustible dust is, by definition, a flammable particulate material suspended in air, the introduction of an ignition source creates a flame front that can move rapidly through the air, consuming the dust. This scenario clearly illustrates a flash fire, so flash fire standards –namely NFPA 2112, Standard on Flame-Resistant Clothing for Protection of Industrial Personnel Against Short-Duration Thermal Exposures from Fire, and NFPA 2113, Standard on Selection, Care, Use, and Maintenance of Flame-Resistant Garments for Protection of Industrial Personnel Against Short-Duration Thermal Exposures from Fire – apply.

You may recall from earlier posts in this series that NFPA 652, Standard on the Fundamentals of Combustible Dust, is currently the one umbrella standard governing combustible dust hazards. Scott emphasizes that Section 8.6.1 of this standard is explicitly clear in proscriptive language on three key points:

1. A flash fire hazard analysis shall be conducted per NFPA 2113
2. When this analysis indicates a flammability hazard, personnel shall be provided with and wear flame resistant garments
3. The flame resistant garments shall comply with NFPA 2112

The standard lists considerations regarding the selection of flame resistant garments, including thermal protective characteristics, physical characteristics, construction, design, fit, durability, comfort, and other criteria. Additional language in the standard regarding flame resistant garments includes:

• The flame resistant garments shall be selected, procured, inspected, worn, and maintained as per NFPA 2112
• Flame resistant or non-melting undergarments shall be used
• Only flame resistant outerwear shall be worn over FR daily wear

OSHA’s Combustible Dust National Emphasis Program (NEP) is also clear on the importance of wearing flame resistant clothing when exposed to flash fire hazards. Section IX.E.9.g. of the NEP states, “…if employees are not wearing protective clothing, such as flame-resistant clothing, in areas of the plant (e.g., bagging areas) where employees may be exposed to potential combustible dust flash fire hazards, then citations under 1910.132(a) may be issued.” This section also references NFPA 2113 requirements for when flame resistant clothing must be used by industrial personnel exposed to flash fire hazards.

Stay tuned for Part 5 of Tyndale’s Combustible Dust series, where you’ll learn what to look for when choosing NFPA-compliant flame resistant clothing to protect your workers from this potentially deadly hazard.