Combustible dust can ignite and lead to catastrophic explosions if not properly managed. To mitigate this danger, thorough combustible dust testing is essential.
According to the Occupational Safety and Health Administration (OSHA), combustible dust is defined as “a finely divided combustible particulate solid that presents a
flash-fire hazard or explosion hazard when suspended in air or the process specific oxidizing medium over a range of concentrations.” Examples include, but are not limited to:
Metal dust, such as aluminum, magnesium, and some forms of iron dusts
- Wood dust
- Coal and other carbon dusts, including carbon black
- Plastic dust, phenolic resins, toner, and additives
- Rubber dust
- Biosolids
- Other organic dust, such as sugar, flour, paper, soap, and dried blood
- Certain textile materials
The list appeared in OSHA’s Revised Combustible Dust National Emphasis Program (NEP) in 2023, which outlines procedures for certified combustible dust inspections. It notes that OSHA Standard 29 CFR 1910.269(v)(11)(xii) addresses control of ignition sources at coal handling operations in electric power plants, however, the Mine Safety and Health Administration (MSHA) has authority in some areas involving coal crushing and conveying processes.
The Combustible Dust Hazard
Combustible dust hazards are a serious threat in many heavy industries. These fine particles can accumulate on surfaces, equipment, and in confined spaces, waiting for a spark to trigger a potentially devastating explosion. Combustible dust can originate from a wide range of materials, including metals, chemicals, plastics, and organic substances, making it a ubiquitous concern.
OSHA established its Combustible Dust NEP in 2007 following a number of combustible dust incidents that resulted in numerous deaths and many serious injuries. However, as a result of a catastrophic incident involving a combustible dust explosion at a sugar refinery, OSHA reissued the NEP the following year to increase its enforcement activities in specific industry groups that experienced either frequent combustible dust incidents or had the potential for combustible dust incidents with catastrophic consequences.
The Importance of Combustible Dust Testing
The primary reason for combustible dust testing is to ensure the safety of workers, facilities, and nearby communities. Identifying potential dust hazards and taking preventive measures can prevent tragic incidents. Testing helps in quantifying the risks associated with combustible dust in a given environment. This data is essential for risk management and mitigation strategies.
Testing methods may include dust characterization, which looks at the composition of the dust particles, their size distribution, and their ignition properties. Explosion severity testing evaluates parameters such as the maximum pressure and rate of pressure rise during an explosion. This data is used to classify the hazard.
Minimum ignition energy (MIE) testing determines the minimum energy required to ignite a dust cloud, which is vital for controlling potential ignition sources, whereas minimum ignition temperature (MIT) testing identifies the lowest temperature at which a dust cloud can ignite. This information is essential for selecting appropriate equipment and designing safe processes.
Dust suppression
Carroll Technologies provides a wide range of dust suppression solutions for adverse environments, such as underground mines. Airflow control and efficient ventilation are essential to increase air quality, so mines rely on air filtration systems and mine sealants to keep dust particles at a safe level.
When it comes to mine sealants, Silent-Seal is leading the way with its effective mine ventilation air sealant foam spray, which is used to spray into areas to make a solid seal to control airflow in underground mining applications.
Carroll Technologies also supplies Bluefield Manufacturing products, including a comprehensive range of brattice ventilation curtains and associated equipment for mines and tunnels. Its lay-flat blower tubing is exclusively manufactured from MSHA approved material and standard sizes are 8in long and ranging between 30in (for yellow brattice) and 35in (for off-white brattice) in diameter. They are made with D-rings, hooks and 5/16in wire rope on the end.
Contact the safety experts at Carroll Technologies today to find out more about mitigating combustible dust risks.
