Dust Hazard Analysis Overview and Services

A dust hazard analysis (DHA) is a mandated formal review of the potential for combustible dust explosions required for all sites that generate, store or handle combustible dusts.
The requirement to perform a DHA for all such facilities was established in 2015 in NFPA 652 – Standard on the Fundamentals of Combustible Dusts – and is enforced by OSHA.
Combustible dust explosions are one of the leading causes of multi-fatality incidents in industry.
Key Takeaways:

• A Dust Hazard Analysis is a document describing fire and explosion hazards related to combustible dust and outlines an implementation plan to correct any issues discovered at the inspected facility.
• A DHA is required for all facilities that generate, handle, or store combustible dusts.
• ADF can perform the DHA, provide dust combustibility testing, and follow up with designs to implement combustible dust mitigation solutions.
• Overview of NFPA 660 standard for combustible dusts coming in September 2024.

Industrial Safety Standards Alert:  NFPA 660, Standard for Combustible Dusts

A new consolidated standard for combustible dusts, NFPA 660, is scheduled to be released in September 2024.  Public input to this new standard was completed in early 2023.  This new standard will replace NFPA 652 and consolidate industry-specific standards (NFPA 61, 484, 654, 655, and 664).

The purpose of this new standard is to improve the consistency of dust mitigation strategies across all industries, provide easier access to combustibility data, resolve conflicting requirements between standards, and clarify enforcement of the standard.

The new standard will begin with an update to NFPA 652 requirements for Dust Hazard Analyses (DHA) and will then include industry-specific requirements broken into chapters and cross-referenced with common appendices and over-arching rules common to all industries.  Stay tuned to ADF Engineering for further updates as information is released by NFPA on this new standard.  In the meantime, remember that completed DHA’s need to be renewed every five years.

What is a dust hazard analysis?

A dust hazard analysis (DHA) is a document that describes the fire and explosion hazards associated with combustible dusts throughout a facility and provides an implementation plan to correct deficiencies in hazard protection.
Conducting a dust hazard analysis is an important aspect of dust safety and process safety. By conducting a hazard analysis, employers can assess the workplace for potential dust hazards and implement measures to control exposures and minimize risk.
This is part of an overall safety management system for combustible dusts and helps to ensure the health and safety of employees.
All facilities that generate, handle, or store combustible dusts are required to complete and maintain a DHA. For new facilities, a DHA may be required by the local Fire Marshal to obtain an operating permit and insurance providers may also enforce this requirement.

Above: Matt Williamson’s recent presentation on combustible dust compliance with evolving regulations

Understanding dust safety and explosion prevention

Combustible dust explosions occur in manufacturing facilities when finely divided solid particles that are capable of burning rapidly, become suspended in air and ignite.
The explosion is caused by a mixture of the dust, air, and an ignition source such as a spark or a hot surface. The dust particles can come from a variety of materials such as wood, coal, flour, sugar, and metal, among others.
If the dust accumulates on surfaces or in the air, the buildup of the dust increases the risk of explosion.
Combustible dust explosions have resulted in many catastrophic incidents and multiple fatalities across a variety of industries.
An industrial combustible dust explosion occurs once every three days on average. These events can be prevented by mitigation of one of the five criteria for a dust explosion to occur – fuel source (dust), ignition source, oxygen, dispersion, and containment. Often, these mitigating solutions are simple. Additionally, many new technologies are available to reliably suppress or disrupt an explosion.
To prevent these incidents, it is important to implement proper dust control measures, including regular cleaning, adequate ventilation, and the use of explosion-proof equipment.