Dust Has Explosive Capability!
At around 6:30 pm, on Saturday, April 26th, an explosion and resulting fire in the sawdust collection system at the Georgia Pacific plywood plant in Corrigan, in East Texas just north of Livingston, severely injured at least seven workers. Three were taken by ambulance to a hospital in nearby Lufkin, while four workers suffering serious burns were Lifeflighted to Memorial Hermann Hospital in Houston’s Texas Medical Center. The collection systems malfunctioned and the dust inside it caught fire and blew up. Investigation continues as to the cause of the tragedy and the plant is closed until that cause can be determined and corrected.
By the following day, April 27th, one of the workers being treated at Hermann Memorial had been upgraded to fair condition, but the other three remained critical. The three workers who were treated in a Lufkin hospital have been released. Initial investigation has revealed that the flash fire started in a “bag house”, a place where plywood dust from a sanding process is collected for environmental safety and to create wood pellets used as a fuel. The extremely fine dust is rated as “very combustible” and indeed, under the right circumstances, it can ignite with explosive results. OSHA investigators are conducting a thorough investigation and the company is fully cooperating. In addition, Georgia Pacific brought the families of the injured workers being treated in Houston to be with them and it has also set up an employee assistance and counseling program.
It’s still an open question as to what caused the mishap. But, in the short term, the company has responded compassionately and seems to be doing a lot of the “right” things in confronting the aftermath of this incident. So, it’s appropriate to focus upon the more generalized and surprisingly lethal danger of fine dust and particulate matter in industrial and manufacturing processes. OSHA has long known that fine industrial dusts can present serious fire hazards. Grain, saw, coal and a wide variety of other industrial dusts have a long, well-documented history of fires, explosions and resulting worker injuries and deaths. In 2008 a fire and explosion at an Imperial Sugar plant, involving powdered sugar, killed 14 workers and injured 36 and the company was fined a record $8.8 million for safety violations.
The agency divides dust into four categories, yet three of the four have explosive properties. And, based upon that it has issued NFPA 654, entitled Standard for the Prevention of Fire and Dust Explosions from the Manufacturing, Processing, and Handling of Combustible Particulate Solids. As therein set out in considerable detail, OSHA recommends the following to minimize the risk of fire or explosion in dusty environments:
1. Use of appropriate electrical equipment and wiring methods;
2. Strict control of static electrical charge, including equipment grounding;
3. Control of smoking, open flames or spark production in exposed areas;
4. Control of mechanical sparks, friction and equipment overheating;
5. Use of properly designed separators to remove foreign materials capable of igniting combustibles;
6. The separation of any heated surfaces from dust exposure or accumulation;
7. Use of properly designed heating, ventilation and storage systems;
8. Strict safety compliance regarding transport equipment and/or cartridge-activated tools; and,
9. Proper inspection, maintenance and repair of all involved equipment and systems.
In addition, the agency has more rules regarding the use of safety equipment, proper clothing, safety procedures, emergency response training and much more. So, if you work in a plant where dust is a by-product, make sure your company is handling that dust safely and that you are not exposed to unnecessary dangers in the event of fire or explosion. If you see obvious problems, please report them to management or OSHA.