Not only that, but he affirmed that a regulatory standard would make employers highly aware of the engineering and safety practices needed to prevent dust explosions.

However, the OSHA chief remained adamant that a new standard may not be the solution to prevent more tragedies. He insisted that the agency's multi-pronged approach, which includes enforcement of standards, combined with education for employers and employees, should be effective enough to fight combustible dust hazards.

“The effectiveness of a standard always depends on how well employers implement the requirements, and many tragic accidents in the last decade could have been avoided or minimized if employers had complied with existing OSHA standards,” Foulke said.

Miller: OSHA “Clinging to a Past”

House Committee Chairman Rep. George Miller, D-Calif., had strong words for Foulke and the agency. He stated that OSHA “has been clinging to a past” that has “turned out be fatal.” He, along with Rep. John Barrows, D-Ga., introduced a bill - the Combustible Dust Explosion and Fire Prevention Act (H.R. 5522) - that would push OSHA to issue mandatory rulemaking regulating combustible industrial dusts.

“I see such an incredible lack of urgency on your part, about the role of your agency to protect workers, that it's astounding,” Miller told Foulke. “Congress will continue to step in until OSHA steps up.”

However, the Chamber of Commerce and several Republican lawmakers, including Rep. Jack Kingston of Savannah, said they were wary of the bill. Kingston called the Miller-Barrow bill a "one-size-fits-all approach" and said various kinds of dust raise different issues. He also said the bill does not call for more inspections and that, even with tougher rules, dust cleanup could remain a problem.

Although CSB is still investigating the causes of the Imperial Sugar refinery explosion, Wright explained the agency has made some preliminary findings. Witnesses reported that “snow-like accumulations of sugar dust” covered the horizontal surfaces of overhead floor joists, rafters, ductwork piping and equipment in the facility, Wright said. When triggered, the accumulated dust is fuel for catastrophic explosions.

“Without accumulated fuel, the most catastrophic type of dust explosion can not and will not occur,” he said, adding that “these type of tragedies are preventable.”

The findings also revealed that the company provided its employees and contractors very little training on combustible dust hazards.

Wright's testimony echoed findings in CSB's 2006 report, which identified 281 industrial dust fires and explosions between 1980 and 2005 that caused 119 deaths and more than 718 injuries.

Amy Beasley Spencer, a senior chemical engineer with the National Fire Protection Association (NFPA), agreed with Wright and suggested that OSHA's rules were too vague to address the hazards associated with combustible dust. The NFPA, a nonprofit and nongovernmental organization, has already established voluntary consensus guidelines to control combustible dust hazards and prevent dust explosions. CSB said in its report the standards are effective in preventive catastrophic explosions caused by combustible dust, but because they are voluntary, “their adoption and enforcement is inconsistent and largely ineffective.”

Foulke: Careful Consideration Needed Before Adopting NFPA Standards

Foulke told OccupationalHazards.com after the hearing that NFPA standards were useful tools and form the basis for many OSHA standards. He added, however, that he was hesitant in adopting them as standards without careful consideration.

“We have concerns about adopting the NFPA voluntary consensus standards as an OSHA combustible dust standard without carefully thinking about their effectiveness, impact and enforceability,” Foulke said. “In fact, the [Occupational Safety and Health] OSH Act requires us to consider consensus standards while developing OSHA standards.”

OSHA, however, did put in place similar standards for the grain industry in 1987 in response to various grain dust explosions in the late 1970s and early 1980s. According to CSB, OSHA's own review of the standard revealed that it has decreased injuries and fatalities from grain dust explosions by 60 percent.

Tammy Miser, who became a workplace safety advocate after her brother, Shawn Boone, 33, died from burns sustained in a 2003 aluminum dust explosion at the Hayes Lemmerz manufacturing plant in Huntington, Ind., brought a human element to the hearing.

She testified that families dealing with the aftermath of these types of explosions have been waiting years for OSHA to act. She recalled her brother's last breath and last words, “I'm in a world of hurt,” and asserted that an OSHA standard would have prevented the incident that caused her brother's death as well as the explosion at Imperial Sugar.

“I truly feel for the Imperial Sugar Plant families that have horrible injuries and who have had deaths,” she said. “I know where they are, where they have been and where they are going and I am truly disgusted and, to be honest, hurt. It is the same hurt I felt after the loss of my brother, because I knew the knowledge was there that could have prevented this and saved him.”