COMBUSTIBLE DUST: A HOT TOPIC
On Feb. 7, 2008, a combustible dust explosion ripped through the Imperial Sugar Co. refinery in Port Wentworth, Ga., killing 14 employees and injuring dozens. The incident triggered $8 million in proposed OSHA fines, a Senate hearing, a renewed call for an OSHA standard and widespread concerns about combustible dust hazards. It also prompted Imperial Sugar to make some changes in its facilities and procedures — including outfitting all workers in fire-resistant (FR) clothing.
“Post-event, we have required all employees and visitors to the manufacturing areas to wear fire-resistant clothing. It’s a blanket requirement and one that is we believe quite conservative,” says Ron Allen, who joined Imperial Sugar as senior director of environmental, health, safety and quality in March 2009. “It’s probably unusual for a manufacturer of dry product to require fire-resistant clothing plant-wide for all employees.”
Scott Margolin, international technical director at Westex Inc., acknowledges that in the event of a combustible dust incident, some fatalities may be unavoidable because of explosions, entrapment or sustained fire. But “vastly more people” often are involved in the flash fire portion of the event, he says.
“If it doesn’t ignite your clothes, you’re probably going to live. And if it does, you’re probably not,” Margolin says. “FR clothing can make a huge contribution to worker safety in that area.”
A COMBUSTIBLE DUST STANDARD
On Oct. 21, 2009, OSHA published an Advance Notice of Proposed Rulemaking as an initial step in developing a standard to address the hazards of combustible dust. Ron Allen represented Imperial Sugar at OSHA’s Dec. 14, 2009, stakeholder meetings on this issue.
“We are strong advocates for an OSHA standard,” he says. “I came away [from the stakeholder meeting] with an appreciation that there are many different opinions that will influence the final standard.”
According to Allen, OSHA representatives “seemed to sincerely have an open mind and are listening to the various stakeholders as they attempt to put together this new standard.” He adds that he’d like to see a combustible dust standard with specification language as opposed to performance language.
“Performance standards are very attractive on the surface, but could be much more difficult to administer than a specification standard,” he points out. “We think that specification language actually serves as an education. It helps employers, particularly small employers, who may not have a great deal of technical resource to understand what they must do to protect their employees from combustible dust fires and explosions.”
“Combustible dust is a hot-button issue with OSHA and FR,” says Margolin, who also attended the December 2009 OSHA stakeholder meetings on the development of a combustible dust standard. “The first line of defense of any of these things is to engineer the hazard out or down,” he explains.
“Flame-resistant clothing, while it is admittedly the last line of defense after behavioral and engineering safety have been addressed, cannot and must not be overlooked. Just because a car has crumple zones and impact-absorbing bumpers and air bags does not mean you can forget to put on your seat belt,” Margolin says. “Same kind of logic.”
A COST-EFFECTIVE SOLUTION
“OSHA has clearly embarked on a path that’s going to result in a rule on combustible dust,” says Margolin. The big questions to me seems to be about scope, and what language [of existing NFPA standards], if any, will make it in.”
According to Margolin, the meetings focused on existing NFPA consensus standards, the potential scope of a standard, economic impact and hazard mitigation. FR clothing also entered the discussion, particularly in terms of economic impact. Margolin is quick to point out just how cost-efficient FR clothing can be.
“Body burn is the second most expensive hospitalization in the U.S.,” he says. “Putting everybody who remotely needs FR clothing in it for the rest of their careers costs vastly less than the first year of medical expenses alone for the burn injuries that are already happening, much less the ongoing medical costs, insurance, workers compensation, counseling, fines and lawsuits.”
Overall, Margolin was encouraged by what he calls an obvious intent to develop and implement a standard for combustible dust. “It’s not a matter of if but when they will put out a rule on combustible dust,” he says.
The types of dust identified by OSHA as being likely to cause dust deflagrations, other fires, or explosions include but are not limited to:
- Metal dust such as aluminum and magnesium.
- Wood dust
- Coal and other carbon dusts
- Plastic dust and additives
- Other organic dust such as sugar, flour, paper, soap, and dried blood.
- Certain textile materials.
The industries that handle these combustible dusts include, but are not limited to:
- Food Products
- Forest and furniture products
- Metal processing
- Tire and rubber manufacturing plants
- Paper products
- Wastewater treatment
- Recycling operations (metal, paper, and plastic.)
- Coal dust in coal handling and processing facilities.
If your industry falls into one of these categories you should probably start a process to determine if you have a potential problem waiting to happen and figure out a course of action. Eventually OSHA will make a rule and being ahead of the curve will put you in a good position.
Excerpts from January 2010 EHS Today magazine article by Laura Walter