The NFPA 652 Standard on the Fundamentals of Combustible Dust is the starting point for all combustible dust users. Initially released in 2015, NFPA 652 is the newest of the NFPA Standards covering the combustible dust hazards and was created to educate and promote safety to facilities handling combustible dust.
One of the major changes to come out of this new Standard is the requirement for facilities to conduct what is termed a Dust Hazard Analysis, or DHA. This new term, DHA, was created to differentiate the Dust Hazard Analysis from the more detailed and complex method known as a PHA, or Process Hazard Analysis, which is a requirement of OSHA’s Process Safety Management Standard.
For facilities or processes that handle dust, the owner/operator of that process has a responsibility to determine if the dust handled poses a combustible dust fire or explosion hazard. Additionally, the requirement for completing a DHA extends not only to new processes, but also extends retroactively to all facilities handling combustible dust regardless of when the facility was constructed.
The new deadline given in NFPA 652, 2019 Edition for completion of the Dust Hazard Analysis has been extended to September 7th, 2020. However, other industry-specific Standards such as NFPA 61 have different deadlines for completion. All combustible dust users are also required to show reasonable progress completed between now and the deadline.
What Is A Dust Hazard Analysis?
Dust Hazard Analysis, or DHA, is a systematic review with the intent to both Identify and Evaluate the risk of fire and explosion hazards within a facility or process handling Combustible Dust. The DHA is effectively your Road Map to Combustible Dust Safety.
An effective DHA will achieve three goals:
- IDENTIFY where dust hazards exist within the process or facility and the risk posed.
- EVALUATE what safeguards are currently in place to protect the facility or process.
- RECOMMEND where additional safeguards should be implemented based on NFPA requirements and industry best practices.
NFPA 652 provides specific details regarding the DHA requirements in Chapter 7 and even offers an example of how a DHA should be completed in the Annex. Additionally, the Center for Chemical Process Safety (CCPS) has published Guidelines for Hazard Evaluation Procedures which provides methods for hazard analysis and examples of how each method can be used.