Of the many hazards workers can encounter, one that is easily overlooked is combustible dust. This hazard is present wherever materials are manufactured, refined, or re-purposed when dust is created as a byproduct. In certain conditions this dust can create a flash fire which can seriously injure and cause fatalities to anyone working in that area.
How do we define combustible dust?
Combustible dust as defined by OSHA is, “a solid material composed of distinct particles or pieces, regardless of size, shape or chemical composition, which can present a fire or deflagration hazard when suspended in air or some other oxidizing medium over a range of concentrations.”
Watch Tyndale’s VP of Technical, Scott Margolin define and explain combustible dust hazards:
Workers and management often fail to recognize the serious nature of combustible dust hazards. It is important to know the risks, safety standards, and guidelines for protection against this hazard.
Until recently there were numerous standards which specifically covered a combustible dust hazard, but each was industry-specific and none covered all aspects. As a result, NFPA put out a new “umbrella” standard which is intended to supersede all of the existing combustible dust standards. This new standard, NFPA 652, recognizes that combustible dust is a flash fire hazard and has proscriptive language requiring FRC In terms of personal protection against those hazards it directs us to NFPA 2112 and NFPA 2113 which are companion standards outlining protection against flash fire hazards, including combustible dust.
Another key point to understanding a combustible dust hazard is what’s known as a KST value. KST quantifies how explosive the dust can be; the higher the KST value, the higher its explosive potential. Critical fact: any KST value over 0 (zero) presents a flash fire hazard and requires flame resistant garments and PPE compliant with NFPA 2112 and NFPA 2113 standards. In fact, the majority of the most lethal combustible dust events in the USA have occurred with “low” KST dusts.
Of all the flash fire hazards combustible dust is one the most difficult to detect and identify. FR clothing is recommended when entering any area where flash fires are a possibility. These proactive steps can prevent serious injury and reduce the chances of loss of life.