Ruminations on Combustible Dust

Despite the excellent presentations by USMWF's Tammy Miser, the Chemical Safety Board's William Wright and NFPA's Amy Spencer, the image that remains in my head from last week's congressional hearing on combustible dust was Ranking Member Howard "Buck" McKeon's performance.  After the aforementioned witnesses made common-sense appeals in support of an OSHA standard modeled on National Fire Protection Association (NFPA) standards, Congressman McKeon (R-CA) made unconvincing claims that such rules are so very complicated.  Surely, no simple small businessman could ever be expected to comply with them. 

I say: "Phooey!"

No matter if you're big or small, urban or rural, family-owned or multi-national, if you are an employer, you have the legal responsibility to provide a safe workplace for your employees.  And if your production process involves or creates combustible dust, you'd better have a risk management plan in place to prevent explosions and fires.

The Savannah Morning News is reporting that a portion of Imperial Sugar's refinery in Gramercy, Louisiana has been shut down voluntarily by the company because of an imminent danger situation related to combustible powered-sugar dust.  (The company has two refineries, the one in Port Wentworth, Georgia and the other in Gramercy, LA.)  In "Inspection Triggers Shutdown of Part of Imperial Sugar Plant in Louisiana," reporter Larry Peterson writes that the inspection at the Louisiana facility is part of OSHA's special emphasis program on combustible dust hazards that was launched in October 2007. 

The story notes that the plant provides jobs for 275 Imperial employees and 100 contractors.  A blurb in last year's Houston Business Journal notes that the Louisiana Imperial workers are represented by the United Food and Commerical Workers (Local 1167-P).  As provided by Section 8(e) of the OSH Act, I hope a worker representative was participating in this special inspection.  I'm simply wondering because the Savannah Morning News story only mentions:

"The company said it's working with OSHA and 'third party experts to ensure that the area is safe for Imperial Sugar employees.  The observations and recommendations by OSHA inspectors have been helpful to our pursuit to develop improved practices for sugar dust management,' said Imperial Sugar President John Sheptor."

Oh yes, I really hope the "experts" include workers who are the most knowledgeable about conditions in the plant.

While thinking about the explosion hazard created by certain types of dust, I spent some time reviewing OSHA's instruction document for combustible dust inspections.  OSHA's CPL 03-00-008 provides guidance to OSHA inspectors and explains certain legal criteria for issuing citations for hazardous conditions.  Reading the directive makes me glad to know there are talented individuals out there who take on the challenging work of being an OSHA inspector. 

An OSHA inspector has to be able to interpret the following:

"Annex D of NFPA 654 contains guidance on dust layer characterization and precautions.  It indicates that immediate clean-up is warranted whenever the dust layer of 1/32 inch thickness accumulates over a surface area of at least 5% of the floor area of the facility or any given room.  The 5% factor should not be used if the floor area exceeds 20,000 ft2, in which case a 1,000 ft2 layer of dust is the upper limit." 

I suspect this means that inspectors use their tape measures a lot to map out shop floor dimensions, but what about the accumulation on other surface areas?

"Accumulations on overhead beams, joists, ducts, the tops of equipment, and other surfaces should be included when determining the dust coverage area.  Even verticle surfaces should be included if the dust is adhering to them.  Rough calculations show that the available surface area of bar joists is approximately 5% of the floor area and the equivalent surface area for steel beams can be as high as 10%."

OK. So it's not just the shop floor, but all these other surfaces that need to be taken into account for the 5% rule-of-thumb.  Clearly, effective dust-control methods should be a very high priority for these companies.

"Citations for violations of 1910.22(a)(1) [General walking-working surface standard] shall be issued when the levels of dust accumulations exist in places of employment (except floors of workrooms and storage areas), passageways, and service rooms, in such depths that they can present explosion, deflagration or other fire hazards."

Very well.  When the dust accumulation exists on floors, the inspector is supposed to cite section (a)(2), not (a)(1).  But, the inspector is also warned:

"...small amounts of dust accumulations in isolated spots of the floor or other areas would not normally be classified as a violation of the housekeeping requirement under this national emphasis program."

So maybe you can't cite the hazard afterall. 

"In order to substantiate housekeeping violations, compliance safety and health officers shall take representative measurements.  Thickness measurements must be made at several locations within the sampling area.  ...As part of determining whether the housekeeping violation is serious, the inspector should determine whether the dust is combustible or can cause deflagration by submitting the sample to Salt Lake Technical Center and obtaining its analyses."

Hmmm....what about taking a photograph to document the amount of dust I observed?  Remember, however:

"Because of its spark-producing potential, no equipment, including cameras with electronic flashes or electrical equipment shall be used in hazardous (classified) locations of the facilities, unless the equipment is intrinsically safe, approved or safe, as defined in 29 CFR 1910.307(b) for use in these types of areas."

Sheesh.  An OSHA inspector's job is much harder than it seems, and those are only a few small excerpts from the 43-page OSHA directive.

My hat's off to OSHA inspectors.

All these ruminations about combustible dust makes me wonder:  Should we simply require employers with combustible dust hazards to write and implement a written dust-control and explosion-prevention program based on NPFA's standards?  Then, if an inspector sees dust accumulation or other explosion hazards, s/he doesn't have to maneuver with Department of Labor lawyers to make sure the exact supra-sub-sub section of the standard is written on the citation.  Instead, the employer is simply cited for violating their own written plan. 

The responsibility for an effective dust-control program (or any hazard control measure for that matter) belongs to the employer, not the OSHA inspector.  If the OSHA inspector deems it ineffective, the burden should be on the employer to demonstrate that it is.  Not the other way around.