[Federal Register: October 21, 2009 (Volume 74, Number 202)][Proposed Rules]
[Page 54333-54347]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr21oc09-25]
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Part III
Department of Labor
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Occupational Safety and Health Administration
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29 CFR Part 1910
Combustible Dust; Proposed Rule
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DEPARTMENT OF LABOR
Occupational Safety and Health Administration
29 CFR Part 1910
[Docket No. OSHA-2009-0023]
RIN 1218-AC41
Combustible Dust
AGENCY: Occupational Safety and Health Administration (OSHA), Labor.
ACTION: Advance notice of proposed rulemaking.
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SUMMARY: In this advance notice of proposed rulemaking (ANPR), OSHA is
requesting comments, including data and other information, on issues
related to the hazards of combustible dust in the workplace. For the
purposes of this notice, the term "combustible dust" includes all
combustible particulate solids of any size, shape, or chemical
composition that could present a fire or deflagration hazard when
suspended in air or other oxidizing medium. OSHA plans to use the
information received in response to this notice in developing a
proposed standard for combustible dust.
DATES: Submit comments in response to this ANPR by January 19, 2010.
ADDRESSES: Submit comments as follows:
Electronic. Submit comments electronically at http://www.regulations.gov,
which is the Federal eRulemaking Portal. Follow the instructions online
for submitting comments.
Facsimile. Commenters may fax submissions, including
attachments, that are no longer than 10 pages in length to the OSHA
Docket Office at (202) 693-1648; OSHA does not require hard copies of
these documents. Commenters must submit lengthy attachments that
supplement these documents (e.g., studies, journal articles), in
triplicate hard copy, to the OSHA Docket Office, Technical Data Center,
Room N-2625, U.S. Department of Labor, 200 Constitution Ave., NW.,
Washington, DC 20210. These attachments must clearly identify the
commenter's name, date, subject, and docket number (i.e., OSHA-2009-
0023) so the Agency can attach them to the appropriate comments.
Regular mail, express delivery, hand (courier) delivery,
and messenger service. Submit three copies of comments and any
additional material (e.g., studies, journal articles) to the OSHA
Docket Office, Docket No. OSHA-2009-0023 (or Regulation Identifier
Number (RIN) 1218-AC41), Technical Data Center, Room N-2625, U.S.
Department of Labor, 200 Constitution Avenue, NW., Washington, DC
20210; telephone (202) 693-2350 (TDY number: (877) 889-5627). Note that
security procedures may result in significant delays in receiving
comments and other written materials by regular mail. Contact the OSHA
Docket Office for information about security procedures concerning
delivery of materials by express delivery, hand delivery, and messenger
service. The hours of operation for the OSHA Docket Office are 8:15
a.m.-4:45 p.m., e.t.
Instructions. All submissions must include the Agency name
and the OSHA docket number or RIN for this rulemaking (i.e., OSHA
Docket No. OSHA-2009-0023 or RIN 1218-AC41). Submissions, including any
personal information provided, are placed in the public docket without
change and will be available online at http://www.regulations.gov.
Therefore, the Agency cautions commenters about submitting statements
they do not want made available to the public, or submitting comments
that contain personal information (either about themselves or others)
such as Social Security numbers, birth dates, and medical data.
Docket: To read or download submissions or other material
in the docket, go to http://www.regulations.gov or the OSHA Docket
Office at the address above. While all documents in the docket are
listed in the http://www.regulations.gov index, some information (e.g.,
copyrighted material) is not publicly available to read or download
through this Web site. All submissions, including copyrighted material,
are available for inspection and copying at the OSHA Docket Office.
Contact the OSHA Docket Office for assistance in locating docket
submissions.
FOR FURTHER INFORMATION CONTACT: Information regarding this ANPR is
available from the following sources:
Press inquiries. Contact Jennifer Ashley, Director, OSHA
Office of Communications, Room N-3647, U.S. Department of Labor, 200
Constitution Avenue, NW., Washington, DC 20210; telephone: (202) 693-
1999.
General and technical information. Contact Don Pittenger,
Director, Office of Safety Systems, OSHA Directorate of Standards and
Guidance, Room N-3718, U.S. Department of Labor, 200 Constitution
Avenue, NW., Washington, DC 20210; telephone: (202) 693-2255; fax:
(202) 693-1663.
Copies of this Federal Register notice. Electronic copies
are available at http://www.regulations.gov. This Federal Register
notice, as well as news releases and other relevant information, also
are available at OSHA's Web page at http://www.osha.gov.
SUPPLEMENTARY INFORMATION:
Table of Contents
I. Background
A. Introduction
B. Dust Explosions in Grain Handling Facilities
C. Dust Explosions in Other Industries
D. CSB Combustible Dust Study
E. Congressional Response
F. Existing OSHA Standards
G. Consensus and Industry Standards
H. National Emphasis Program Analysis
I. Regulatory Issues
II. Request for Data, Information, and Comments
A. Industry Background
B. Definition of Combustible Dust
C. Hazard Recognition
D. Hazard Assessment
E. Hazard Communication and Training
F. Consensus, Industry, and Insurance Standards
G. State and Local Codes
H. Engineering Controls
I. Administrative Controls
J. Emergency Response
K. Investigation of Incidents
L. Regulatory Approach
M. Economic Impacts and Benefits
N. Impacts on Small Entities
O. Compliance Assistance
III. Public Participation
IV. Authority and Signature
I. Background
A. Introduction
The hazards of combustible dust encompass a wide array of
materials, industries, and processes. Any combustible material can burn
rapidly when in a finely divided form. Materials that may form
combustible dust include, but are not limited to, wood, coal, plastics,
biosolids, candy, sugar, spice, starch, flour, feed, grain, fertilizer,
tobacco, paper, soap, rubber, drugs, dried blood, dyes, certain
textiles, and metals (such as aluminum and magnesium).
Five elements are needed for a combustible dust explosion to occur.
The first three elements are those necessary for a fire: Fuel, heat,
and an oxidizer. These three elements form the "fire triangle," in
which combustible dust is the fuel, heat is provided by any source of
ignition, and oxygen is present in air and in oxidizers.
The fourth element is dispersal of dust into a cloud of the proper
concentration. These four conditions are necessary for a deflagration,
which is violent combustion accompanied by a pressure wave. The
combustion is rapid, but propagates at a speed less than the speed of
sound.
A fifth element, confinement, is necessary for an explosion.
Confinement can be any enclosure--including, but not limited to, a
building, room, duct, or processing and storage equipment. An explosion
occurs when the pressure developed by a deflagration bursts or ruptures
the enclosure. Together, these five elements (fuel, heat, an oxidizer,
dispersion and confinement) are known as the "dust explosion
pentagon." The minimum explosible concentration is the lowest
concentration of combustible dust suspended in air that will support a
deflagration.\1\
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\1\ The terms "deflagration", "explosion", and "minimum
explosible concentration" are used in this notice as defined in
NFPA 654 (2006 edition) for combustible dust only. This notice does
not address the terms "detonation" or "explosion" as they relate
to materials classified as explosives.
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Secondary explosions or deflagrations occur when pressure waves
from an initial (or primary) deflagration or explosion cause dispersal
and ignition of combustible dust that has accumulated on surfaces.
Secondary explosions are often more devastating than primary explosions
due to the increased amount of fuel and the size of the ignition source
(i.e., the initial event). In some cases, explosions continue to
cascade throughout an area or facility.
OSHA is developing a standard that will comprehensively address the
fire and explosion hazards of combustible dust. The Agency's existing
standards address some, but not all, of the elements needed to protect
workers from these hazards. For example, OSHA's general industry
housekeeping standard (29 CFR 1910.22(a)(1)) addresses accumulations of
dust, including dusts that may be combustible, and the general industry
electrical standard (29 CFR 1910, subpart S) helps to control
electrical ignition hazards. When workers are exposed to hazards not
currently addressed in the OSHA standards, employers are cited under
the General Duty Clause (GDC) specified by Section 5(a)(1) of the
Occupational Safety and Health Act of 1970 (OSH Act; see 29 U.S.C.
654). The information requested in this notice will help the Agency
develop a standard that would better protect workers from the hazards
of combustible dust.
Industries that may have combustible dust hazards include, among
others: Agriculture, animal food manufacturing, grain handling, food
manufacturing, wood product manufacturing, chemical manufacturing,
textile manufacturing, furniture manufacturing, metal processing,
fabricated metal products and machinery manufacturing, pesticide
manufacturing, pharmaceutical manufacturing, tire manufacturing,
production of rubber and plastics, plastics and rubber products
manufacturing, recycling, wastewater treatment, and coal handling and
processing. To determine which industries may be affected by an OSHA
standard regulating combustible dust hazards, OSHA identified
industries that had previous incidents relating to combustible dust.
Table 1 summarizes this data. Incidents were identified using data from
the U.S. Chemical Safety and Hazard Investigation Board (CSB) involving
incidents occurring from 1980 to 2005. For incidents between 2006 and
2008, OSHA used reports gathered by the Web site
"dustexplosions.blogspot.com." Using these two data sources, OSHA
assigned a North American Industry Classification System (NAICS) code
to each incident using the available information. The groups of NAICS
codes in this table were determined by combining similar industries
together that had explosions in the past. Incidents having insufficient
information to assign a NAICS code to the affected establishment were
classified as "unknown." OSHA's preliminary analyses show that, in
industries for which combustible dust fires or explosions have
occurred, there are 426,000 establishments employing 16 million workers
(see Table 1). The table does not show that these industries include
over 333,000 small businesses with 6.5 million employees. It is
possible that some establishments in these industries do not have
significant dust hazards.
Table 1--Industries Having at Least One Recorded Combustible Dust Incident Reported Since 1980, According to
OSHA Research
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Incidents
NAICS group \1\ Name of industry \1\ (1980-2008) Firms \3\ Establishments Employees
\2\ \3\ \3\
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115111.................... Cotton Ginning............... 1 260 279 2,654
221000.................... Utilities, Electric Power Gen 28 6,554 17,174 614,427
311000.................... Food Manufacturing (Except 8 5,820 7,786 834,277
311100, 311200, 311300,
311800, 311900).
311100.................... Animal Food Mfg. (Except 2 176 248 16,202
311119).
311119.................... Other Animal Food Mfg........ 5 1,046 1,549 31,971
311200.................... Grain and Oilseed Milling 5 392 658 31,439
(Except 311221 and 311230).
311221.................... Wet Corn Milling............. 21 33 65 8,875
311230.................... Breakfast Cereal Mfg......... 6 43 66 13,410
311300.................... Sugar & Confectionary Product 5 1,581 1,700 66,341
Mfg. (Except 311313).
311313.................... Beet Sugar Manufacturing..... 6 10 33 6,263
311800.................... Bakeries..................... 4 9,301 10,072 288,393
311900.................... Other Food Manufacturing..... 8 2,768 3,205 161,567
312000.................... Beverage and Tobacco Product 4 2,193 2,379 83,531
Mfg. (Except 312110).
313000.................... Textile Mills................ 11 2,770 3,243 187,766
314000.................... Textile Product Mills........ 2 6,456 6,726 155,586
321000.................... Wood Product Mfg. (Except 28 11,192 12,749 449,650
321113 and 321219).
321113.................... Sawmills..................... 7 3,398 3,731 104,666
321219.................... Reconstituted Wood Prod. Mfg. 14 167 255 22,190
322000.................... Paper Manufacturing.......... 18 3,269 5,139 441,430
324000.................... Petroleum & Coal Products Mfg 1 1,166 2,448 102,997
325000.................... Chemical Mfg. (Except 325188 31 7,737 10,749 514,732
and 325410).
325188.................... Basic Inorganic Chemical Mfg. 11 390 612 40,589
325410.................... Pharmaceutical & Medicine Mfg 8 1,481 1,886 249,743
326000.................... Plastics and Rubber Products 17 11,365 11,454 846,857
Mfg. (Except 326211).
326211.................... Tire Manufacturing........... 5 91 138 53,985
327000.................... Nonmetallic Mineral Prod. Mfg 4 11,332 17,350 482,459
331000.................... Primary Metal Manufacturing.. 32 4,310 5,285 449,914
332000.................... Fabricated Metal Product Mfg. 27 54,969 59,064 1,563,713
333000.................... Machinery Manufacturing...... 7 23,842 26,317 1,126,671
334000.................... Computer, Electronic Equip. 2 12,733 14,548 1,057,485
Mfg.
336000.................... Transportation Equipment Mfg. 16 10,552 12,707 1,622,527
337000.................... Furniture & Related Product 2 4,779 5,148 188,908
Mfg. (Except 337100).
337100.................... Household & Institutional 16 15,878 16,301 354,341
Furniture, Cabinet Mfg.
339000.................... Miscellaneous Manufacturing.. 7 29,925 31,239 686,096
423000.................... Merchant Wholesalers (423110, 4 22,669 27,704 432,265
423210, 423310, 423930).
488000.................... Support Activities for 1 29,416 37,083 579,589
Transportation.
493000.................... Warehousing and Storage...... 1 7,176 13,849 595,325
511000.................... Publishing Industries........ 1 22,874 31,821 1,039,739
561210.................... Facilities Support Services.. 1 1,680 4,115 164,637
562000.................... Waste Management and 3 16,189 19,919 345,334
Remediation Services.
Other..................... Unknown Industry Category.... 42 ........... .............. ...........
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Total........................ 422 347,983 426,794 16,018,544
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Sources:
\1\ North American Industry Classification System, United States, 2008.
\2\ Incident data from U.S. Chemical Safety and Hazard Investigation Board and
http://dustexplosions.blogspot.com.
\3\ County Business Patterns 2006--U.S. Census Bureau.
B. Dust Explosions in Grain Handling Facilities
In the 1970s, agriculture and food processing industries
experienced several combustible dust explosions. A 1977 grain-dust
explosion in Westwago, Louisiana, killed 36 workers. It remains the
deadliest grain-dust explosion of the modern era. Five days later,
another grain-dust explosion in Galveston, Texas, caused the deaths of
9 workers and injured 34 others.\2\ As a result of these and other
grain-dust explosions in the 1970s, OSHA issued a document entitled
"Grain Elevator Industry Hazard Alert," which provided employers,
workers, and other officials with information concerning the hazards
and safe handling of grain.
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\2\ National Academy of Science, International Symposium on
Grain Elevator Explosions, July 11-12, 1978, National Materials
Advisory Board Committee on Evaluation of Industrial Hazards.
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Later in the 1970s, the Agency initiated rulemaking to address the
problem of grain-dust explosions. On December 31, 1987, after extensive
public comment on its proposed rule and several public hearings, OSHA
published its final standard on Grain handling facilities, 29 CFR
1910.272 (52 FR 44592). In its Combustible Dust Hazard Study of
November 2006 (discussed further in Section 1(D) of this notice), the
U.S. Chemical Safety and Hazard Investigation Board stated: "OSHA's
Grain handling facilities standard provides a model for OSHA action
that has proven effective in reducing catastrophic dust explosions in
the grain industry." \3\
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\3\ U.S. Chemical Safety and Hazard Investigation Board
Investigation Report No. 2006-H-1, Combustible Dust Hazard Study;
November 2006, page 67.
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During a review of the Grain handling facilities standard in 2003,
OSHA received comments from union representatives claiming that, since
its promulgation, grain explosions were down 42 percent, and injuries
and deaths from grain explosions were reduced by 60 percent and 70
percent respectively.\4\ Figure 1 shows the number of grain-dust
explosions per year since 1978. For the ten years prior to the standard
(1978-1987), the average number of explosions per year was 20.5. This
average decreased to 10.3 explosions per year from 1988 to 1997 and
further decreased to 6.3 per year from 1998 to 2007. OSHA gathered this
data from the Regulatory Review of OSHA's Grain Handling Standard,\5\
Kansas State University in cooperation with USDA Federal Grain
Inspection Service,\6\ and USDA Grain Inspection, Packers, and
Stockyards Administration.\7\
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\4\ Regulatory Review of OSHA's Grain Handling Standard [29 CFR
1910.272], February 2003.
\5\ Regulatory Review of OSHA's Grain Handling Standard [29 CFR
1910.272], February 2003.
\6\ Kansas State University, in cooperation with USDA Federal
Grain Inspection Service, available online at: http://
www.oznet.ksu.edu/pr_histpubs/Dust_Exp.htm.
\7\ USDA Grain Inspection, Packers, and Stockyards
Administration, personal e-mail communication from USDA to OSHA, Jul
10, 2009, with attachment entitled, "Explosion Data."
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[GRAPHIC] [TIFF OMITTED] TP21OC09.035
C. Dust Explosions in Other Industries
The flammability and explosiveness of various types of organic and
inorganic dusts has been recognized for well over a century. The
devastating effects of secondary explosions resulting from accumulated
dust have also been well documented, particularly since the early years
of the 20th century; the hazards of some dusts, particularly coal dust,
mineral dusts, and flour, were recognized many years before the 20th
century. However, no national organizations focused on the hazards of
combustible dusts until the National Fire Protection Association (NFPA)
established a committee to do so in 1922. The NFPA's work resulted in a
wealth of knowledge about the prevention and control of dust-explosion
hazards in material handling and manufacturing processes. In 1923, NFPA
published the first national consensus standard to address the
prevention of dust explosions in grain terminals and flour mills.\8\
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\8\ Cashdollar, K. L., & Hertzberg, M., eds (1987) Industrial
Dust Explosions, ASTM International, U.S., p. 345.
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Over the past 15 years, a number of industries have experienced
serious dust explosions, causing loss of life and injuries, as well as
property damage. The first of these incidents, an explosion and fire in
a textile factory in Methuen, Massachusetts in 1995, injured 37 people
and destroyed several large buildings.\9\ After a detailed
investigation of this incident, OSHA issued a Hazard Information
Bulletin in 1998 for the textile industry.
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\9\ U.S. Fire Administration Technical Report 110,
Manufacturing Mill Fire, Methuen, MA, December 11, 1995.
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In 1999, an automotive plant near Dearborn, Michigan experienced an
explosion in one of the boilers in its power plant. Analysis of the
explosion indicated that the initial boiler explosion may have caused
accumulated coal dust on plant surfaces to become airborne, fueling a
secondary explosion that destroyed part of the facility. Six workers
were killed and 36 were injured.\10\
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\10\ Michigan Department of Energy, Labor & Economic Growth, CIS
Reaches Historic Settlement Agreement with Ford and UAW, 1999
available online: http://www.michigan.gov/dleg/0,1607,7-154-10573_
11472-52301-,00.html.
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In the same year, there was an explosion at a foundry in
Springfield, Massachusetts, involving powdered phenolic resin in the
iron castings manufacturing process. This explosion killed three
workers and injured nine. Investigators found heavy resin deposits in
ducts and other surfaces. From this finding, they concluded that a
primary explosion in a dust extraction duct had dispersed the settled
dust, and that the dispersed dust then fueled secondary explosions in
the facility.\11\
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\11\ U.S. Department of Labor (USDOL), 1999. Joint Foundry
Explosion Investigation Team Report, Jahn Foundry Corporation,
Springfield, MA, February 25, 1999.
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A rubber-dust explosion at a rubber recycling plant in Vicksburg,
Mississippi in 2002, resulted in five fatalities and seven injuries.
Part of the recycling process involved grinding rubber tires; the
grinding process produced rubber dust, which accumulated on building
surfaces and in a product bagging bin that was not equipped with
explosion vents. A fire started on the roof of the plant. When it
spread to the bagging bin, it dispersed the layers of dust in the bin
and on the surrounding surfaces, fueling an explosion.\12\
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\12\ OSHA, 2002, Region 4 Report on Explosion at Rouse
Polymerics, U.S. Department of Labor.
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A massive explosion in 2003 at a pharmaceuticals device
manufacturing facility in Kinston, North Carolina, injured 38 workers
and killed 6. In a process in which rubber strips were dipped into a
polyethylene slurry, fans were used to help dry the coated rubber,
causing fine polyethylene powder to be disbursed. Employees diligently
cleaned the visible areas of the process room; however, most of the
employees were unaware that combustible polyethylene
dust was accumulating in the enclosed space above the suspended
ceiling, carried there by the building ventilation system. Due to the
extensive damage to the facility, and the deaths of potential
witnesses, investigators were unable to definitively determine the
ignition source or the method of dust dispersal.\13\
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\13\ Investigation Report, Dust Explosion, West Pharmaceutical
Services, Inc., U.S. Chemical Safety and Hazard Investigation Board
(CSB), September 2004.
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That same year, phenolic resin again fueled a fatal dust explosion,
this time in an acoustic insulation manufacturing facility in Corbin,
Kentucky. As workers were cleaning fugitive dust accumulations with
compressed air, a cloud of phenolic resin formed near a malfunctioning
appliance, which likely ignited the cloud of dust. The initial
deflagration dispersed large quantities of combustible dust that had
accumulated on surfaces throughout the facility. The resulting dust
clouds fueled several secondary explosions. The building was destroyed,
7 workers were killed, and 37 were injured.\14\
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\14\ CSB, 2005, Investigation Report, Combustible Dust Fire and
Explosions, CTA Acoustics, Inc., February 2005.
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Even finely divided metals can cause dust explosions. Again in
2003, one worker was killed and several injured in an aluminum dust
explosion at a wheel manufacturing facility. At the point in the
process in which scrap aluminum was reduced to small chips, aluminum
particles were drawn into a dust collector. An initial explosion in the
dust collector spread through the ventilation system, causing a
secondary explosion involving the dust accumulated on overhead beams,
ducts, and other structures.\15\
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\15\ CSB, 2003, Investigation Report, Hayes Lemerz Dust
Explosions and Fire, September 2003.
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As a result of this series of incidents in 2003, OSHA produced a
Safety and Health Information Bulletin (SHIB), Combustible Dust in
Industry: Preventing and Mitigating the Effects of Fire and Explosions.
This widely disseminated guidance document provided employers and
workers with information on combustible dust explosions, including
mitigation. It contains references to both the applicable OSHA
standards and the related industry consensus standards. However,
incidents continued to occur despite the availability of these
standards and the guidance in the SHIB.
In early 2008, a catastrophic incident at a sugar refinery in Port
Wentworth, Georgia, killed 14 workers and seriously injured 36 others.
The CSB investigated \16\ and determined that an initial dust explosion
occurred in an enclosed steel belt conveyor below three 105-foot-tall
silos, most likely ignited by an overheated conveyor bearing. Large
quantities of sugar dust that had accumulated on surfaces throughout
the plant fueled a series of massive secondary explosions and fires,
destroying much of the facility. The plant had a history of previous,
smaller initial explosion incidents that did not result in significant
damage or secondary explosions. The fine OSHA proposed for this
employer is the third-largest fine ever proposed for a single incident.
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\16\ U.S. Chemical Safety and Hazard Investigation Board
Investigation Report No. 2008-05-1-GA, Sugar Dust Explosion and
Fire; September 2009.
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The sugar plant incident highlighted a lack of hazard awareness and
a failure to comply with existing Federal standards and State codes.
OSHA took prompt action to further heighten awareness of this hazard by
producing additional guidance for employers and workers, including a
Web page, a fact sheet, and a poster. The Agency mailed the SHIB
directly to 30,000 employers suspected of having combustible dust
hazards, and also focused enforcement efforts on sugar plants.
D. CSB Combustible Dust Study
The CSB conducted a study of dust explosion incidents between 1980
and 2005. The 2006 report from that study identified 281 incidents that
killed 119 workers and injured 718.\17\ From 2006 through 2008, OSHA
has found records of an additional 16 deaths and 84 injuries; these
records are included in Table 1 above. Among CSB's findings and
conclusions were the following:
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\17\ U.S. Chemical Safety and Hazard Investigation Board
Investigation Report No. 2006-H-1, Combustible Dust Hazard Study;
November 2006, p. 31.
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Many industry and safety professionals lack awareness of
combustible dust hazards.
The widely recognized standards of good engineering
practice in the NFPA's voluntary consensus standards were not being
followed in many facilities.
State and local fire codes were ineffective as a viable
mechanism to reduce dust explosion risks in general industry
nationwide.
OSHA's focus has been on enforcement activities in
response to combustible dust incidents.
The only comprehensive OSHA standard that specifically
addresses combustible dust hazards (the 1987 Grain handling facilities
standard) has effectively reduced the risk and consequences of grain-
dust explosions, and incorporates many of the same principles that can
be found in the NFPA standards.
The report of CSB's combustible dust study also listed five
recommendations for OSHA. This notice addresses the first of these
recommendations:
"Issue a standard designed to prevent combustible dust fires and
explosions in general industry. Base the standard on current National
Fire Protection Association (NFPA) dust explosion standards (including
NFPA 654 and NFPA 484), and include at least
Hazard assessment,
engineering controls,
housekeeping,
building design,
explosion protection,
operating procedures, and
worker training."
The second CSB recommendation requested that OSHA revise its Hazard
Communication Standard (HCS) (29 CFR 1910.1200) to clarify the coverage
and requirements related to combustible dust. This recommendation is
being addressed in a separate rulemaking.
The third and fourth CSB recommendations suggested that OSHA,
respectively, communicate with the United Nations Economic Commission
for Europe the need to amend the Globally Harmonized System to address
combustible dust hazards, and provide combustible dust-related training
through the OSHA Training Institute. Both of these recommendations have
been accomplished.
The fifth CSB recommendation suggested that OSHA initiate a Special
Emphasis Program for Combustible Dust, to include an outreach program
focused on the information in OSHA's Safety and Health Information
Bulletin, Combustible Dust in Industry: Preventing and Mitigating the
Effects of Fire and Explosions. The Agency went beyond CSB's
recommendation and implemented a National Emphasis Program (NEP) to
increase OSHA's enforcement activities throughout the country and to
focus on specific industry groups that experienced either frequent
combustible dust incidents or combustible dust incidents with
catastrophic consequences. The NEP was launched on October 17, 2007,
and is ongoing. It was revised in 2008 to more closely focus on sugar
plants.
E. Congressional Response
Interest intensified in regulatory action during the months after
the sugar-plant incident in 2008. Employee unions expressed support for
CSB's rulemaking recommendations. On May 1, 2008, the U.S. House of
Representatives introduced a bill entitled H.R. 5522, Worker Protection
Against Combustible Dust Explosions and Fires Act of 2008. This bill
directed OSHA to issue an interim combustible dust rule and an amendment
to the HCS in 90 days, and a final rule in 18 months. H.R. 5522 was passed
by the House and referred to the Senate.
Two Congressional hearings were held on H.R. 5522. The first
hearing was held by the House Committee on Education and Labor on March
12, 2008, and the second hearing was held by the Subcommittee on
Employment and Workplace Safety of the Senate Housing, Education, Labor
and Pensions Committee on July 29, 2008. Assistant Secretary of Labor
Ed Foulke testified for OSHA at these hearings; also testifying were
representatives of CSB, NFPA, and the Georgia sugar plant that
sustained the 2008 explosion.
On February 4, 2009, H.R. 849, Worker Protection Against
Combustible Dust Explosions and Fires Act of 2009, was introduced into
the current session of Congress. The provisions of this resolution are
the same as H.R. 5522.
F. Existing OSHA Standards
The Agency does not have a single, comprehensive standard that
addresses combustible dust hazards across all industries. Current OSHA
standards provide limited protection from dust hazards in two ways:
First, certain standards address some dust hazards for specific
industries. Among these standards are the following:
29 CFR 1910.261--Pulp, paper, and paperboard mills.
29 CFR 1910.263--Bakery equipment.
29 CFR 1910.265--Sawmills.
29 CFR 1910.269--Electric power generation, transmission,
and distribution.
29 CFR 1910.272--Grain handling facilities.
Second, some general industry standards address one or more of the
elements that can contribute to dust explosions, such as ignition
sources and dust accumulations, or the standards require the
communication of information that employers and workers need to address
dust hazards. Among these standards are:
29 CFR 1910.22(a)--Housekeeping.
29 CFR 1910.178--Powered industrial trucks.
29 CFR 1910 Subpart Q--Welding, Cutting, and Brazing.
29 CFR 1910. 269--Electric power generation, transmission,
and distribution.
29 CFR 1910.307--Hazardous (classified) locations.
29 CFR 1910.334(d)--Occasional use of flammable or
ignitable materials.
29 CFR 1910.1200--Hazard Communication.
As noted earlier, OSHA's existing standards for combustible dust do
not provide a comprehensive set of requirements to fully address all of
the prevention and mitigation methods specific to combustible dust
hazards. Accordingly, some ignition sources are specifically covered
(e.g., electrical installations, powered industrial trucks), while
other ignition sources are not covered (e.g., mechanical sparks,
friction, open flames). Additionally, OSHA standards address the
accumulation of fugitive dust (i.e., dust that escapes from equipment
or areas where it is normally present), but do not include measures
that would prevent the escape of dust in the first place. Also, many
built-in engineering controls (including the design of facilities,
explosion venting, suppression systems, and explosion protection
systems) are not addressed in the OSHA standards. OSHA is asking a
series of questions about the need to address these areas in a new
combustible dust standard to afford adequate and complete protection to
workers.
G. Consensus and Industry Standards
NFPA issues a number of national consensus standards that address
the hazards of combustible dust. For example, NFPA 654, Standard for
the Prevention of Fire and Dust Explosions from the Manufacturing,
Processing, and Handling of Combustible Particulate Solids, addresses
the hazards of combustible dust in a general manner. Specific
industries are excluded from NFPA 654, but are covered by other NFPA
standards, including NFPA 61, Standard for the Prevention of Fires and
Dust Explosions in Agricultural and Food Processing Facilities; NFPA
484, Standard for Combustible Metals; NFPA 655, Standard for Prevention
of Sulfur Fires and Explosions; and NFPA 664, Standard for the
Prevention of Fires and Explosions in Wood Processing and Woodworking
Facilities.
These five NFPA combustible dust standards have mandatory secondary
references to a large number of other standards. The 2006 edition of
NFPA 654 mandates compliance with 36 other NFPA standards. These 36
secondary references, in turn, reference additional standards. In
effect, no one standard comprehensively addresses the hazards of
combustible dust, which may pose difficulties for some employers trying
to develop programs to mitigate combustible dust hazards. In addition,
the provisions of these five NFPA standards differ, which may add to
these difficulties. Some elements of protection are addressed in some
standards but not in others; other elements are addressed in different
ways in the various standards. For example, NFPA 61, 484, and 654
contain provisions for drive belts, while NFPA 655 and 664 have no
provisions directly addressing drive belts.
In addition to the NFPA standards listed above, NFPA issues a
number of standards that cover the design and installation of
protection systems specific to deflagration and explosion hazards,
including combustible dust. Two of these standards are NFPA 68,
Standard on Explosions Protection by Deflagration Venting, and NFPA 69,
Standard on Explosion Prevention Systems. NFPA also has a series of
standards that cover automatic fire suppression and alarm systems for a
variety of facilities and hazards, but are not specific to combustible
dust, deflagrations, or explosions.
A large majority of State and local jurisdictions in the United
States have adopted the NFPA standards because both of the model fire
codes used in this country (i.e., International Code Council's
International Fire Code, and NFPA's Fire Code) make these NFPA
standards mandatory. However, the 2006 report on CSB's combustible dust
study indicates that enforcement of these fire codes at the State and
local level is "inconsistent and largely ineffective." For example,
the 2008 sugar-plant incident occurred in Georgia, a State having a
fire code that mandated compliance with, among other combustible dust-
related consensus standards, NFPA 61, Standard for the Prevention of
Fires and Dust Explosions in Agricultural and Food Processing
Facilities.
NFPA standards are updated on a regular basis, usually every three
years. In the Agency's experience, consensus standards incorporated by
reference into OSHA rules quickly become out of date, making it
difficult for employers to comply when the out-of-date consensus
standards become difficult to obtain. Furthermore, OSHA cannot legally
update NFPA or other consensus standards used in its rules by referring
to the "current" or "most recent" edition of the consensus
standards.
Despite the aforementioned challenges with the application and
enforcement of NFPA standards, the standards are used to a significant
extent throughout industry, particularly by large companies,
engineering consultants, and firms designing facilities with
combustible dust hazards. Therefore, OSHA is asking for comment
on how best to incorporate the provisions of the consensus standards.
H. National Emphasis Program Analysis
OSHA analyzed the results of its Combustible Dust National Emphasis
Program (NEP) to better understand where combustible dust hazards exist
and where improvements may be needed to ensure that workers are
protected from combustible dust hazards. Between November 1, 2007, and
February 24, 2009, OSHA conducted 813 inspections under this NEP--665
in States under Federal OSHA authority, and 148 in States having an
OSHA-approved State Plan. OSHA cited employers for 3,662 violations.
Of the 665 Federal NEP inspections, 160 citations were issued under
the General Duty Clause (GDC) for hazards related to combustible dust.
Therefore, the rate of GDC usage for combustible-dust-related hazards
in the NEP inspections was 24 percent during the time period noted
above (These statistics were derived from the information available at
the time this notice was developed; the numbers may change over time
through the informal conference and settlement process.)
The 160 GDC violations referenced 32 different industry or
consensus standards developed by 6 different standards-developing
organizations. The eleven most frequently referenced consensus
standards were as follows, in descending order of frequency:
NFPA 654, Standard for the Prevention of Fire and Dust
Explosions from the Manufacturing, Processing, and Handling of
Combustible Particulate Solids.
NFPA 664, Standard for the Prevention of Fires and
Explosions in Wood Processing and Woodworking Facilities.
NFPA 61, Standard for the Prevention of Fires and Dust
Explosions in Agricultural and Food Processing Facilities.
NFPA 69, Standard on Explosion Prevention Systems.
NFPA 484, Standard for Combustible Metals.
NFPA 68, Standard on Explosion Protection by Deflagration
Venting.
ASME B20.1, Standard for Conveyors and Related Equipment.
ANSI/ITSDF B56.1, Safety Standard for Low and High Lift
Trucks.
FM Global Loss Prevention Data Sheet 7-76, Prevention and
Mitigation of Combustible Dust Explosions and Fires.
NFPA 505, Standard on Powered Industrial Trucks.
NFPA 86, Standard on Ovens and Furnaces.
It has been necessary to cite the GDC extensively to address the
various aspects of combustible dust hazards. GDC citations focused on
each of the elements that could contribute to a dust fire or explosion,
including containment or control of dust, isolation or control of
ignition sources, and explosion venting or suppression systems. The
following hazards were the most commonly cited GDC violations:
Baghouse dust collectors located inside a building without
proper explosion protection systems, such as explosion venting or
explosion suppression systems.
Deflagration isolation systems not provided to prevent
deflagration propagation from dust collectors to other parts of the
plant.
Rooms with excessive dust accumulations not equipped with
explosion relief venting to the exterior.
Horizontal surfaces not minimized to prevent accumulation
of dust.
Air from dust collectors recycled through ductwork back
into the work area.
Legs of bucket elevator enclosures not equipped with
explosion relief venting.
Explosion vents on bucket elevator enclosures directed
into work areas and not to a safe, outside location away from
platforms, means of egress, or other potentially occupied areas.
Pulverizers not provided with explosion venting or
deflagration suppression systems.
Dust collection system ductwork not constructed of metal.
Open-flame propane heater used for comfort heating in an
area where agricultural products were milled.
Equipment (such as grinders and shakers) not maintained to
minimize the leakage of combustible dust into the surrounding area.
Electric grinders used in dust hazard areas without a hot-
work permit system.
This list provides some indication of the areas in which current
standards do not cover combustible dust hazards in general industry.
Only the last two items on the list are administrative or operational
in nature, involving maintenance, work practices, policies, and
procedures. The other ten items involve engineering controls, such as
fixed facilities or protection features built into the plant or the
processing systems. These specific GDC violations point to areas that
may be appropriate to cover in a prospective OSHA standard for
combustible dust. Therefore, OSHA arranged the questions it is asking
to solicit information separately for engineering controls and
administrative controls.
The main finding of this NEP analysis is the unusually high rate of
GDC use in combustible dust inspections (24 percent). Ordinarily, the
GDC is used on a much more limited basis. For the same time period
between November 1, 2007 and February 24, 2009, the 48,969 Federal OSHA
inspections that were conducted outside the NEP yielded 1,736 GDC
citations (a rate of 3.5 percent). Therefore, the GDC was used almost
seven times as often for combustible-dust-related citations than for
all other citations. This unusually high proportion suggests the need
for a comprehensive OSHA standard.
I. Regulatory Issues
The CSB recommended that OSHA issue a standard to prevent
combustible dust fires and explosions. The CSB determined that many
tragic accidents in the past decade could have been avoided or
minimized if employers had complied with applicable national consensus
standards. OSHA recognizes that regulatory action needs to be
considered as part of its overall approach to protecting workers from
combustible dust hazards. The Agency already has made significant
efforts to address the need for additional information and training on
combustible dust hazards. Among these efforts are OSHA's SHIB, fact
sheet, and poster; additional information provided on the Agency's Web
site; outreach to employers; and specialized training for compliance
officers. In addition, through the NEP, OSHA also enhanced compliance
through strengthened enforcement of existing standards and citations
under the General Duty Clause.
The existing regulatory regime is fragmented and incomplete. The
Agency's analysis of the combustible dust NEP, above, shows that
existing OSHA standards do not regulate important elements of
combustible dust hazards. The consensus standards related to
combustible dust are large, complex, numerous, and interrelated, which
make it difficult for employers to comply with them. In addition, where
these consensus standards have been adopted as part of State or local
codes, available evidence shows that they are poorly enforced at the
local and State levels.\18\ Therefore, OSHA has preliminarily concluded
that national consensus standards alone, even when adopted by State or local
governments, are insufficient to adequately protect workers from these hazards.
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\18\ U.S. Chemical Safety and Hazard Investigation Board
Investigation Report No. 2006-H-1, Combustible Dust Hazard Study;
November 2006, page 68.
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As noted earlier, combustible dust hazards are present in a wide
range of industries. Many different materials, both organic and
inorganic, can produce dust capable of fueling explosions. OSHA plans
to evaluate affected industries to determine the most effective way to
regulate the combustible dust hazards present in these industries. It
may be appropriate for OSHA to treat specific industries differently,
based at least in part on current national consensus standards.
OSHA must consider many factors in developing a comprehensive
standard for combustible dust. Some of these factors relate directly to
the characteristics of the hazard and the range of variables
encountered in the workplace, which affect the combustibility or
explosibility of dusts. For any dust materials having a specific
chemical composition, the chance of a combustible dust deflagration
depends on many variables, including:
Size of particles
Shape of particles
Particle surface-area-to-volume ratio
Agglomeration (how well particles stick together)
Impurities present in the material
Moisture content of the material
The predisbursal dust layer depth and location
The concentration of particles in a dust cloud
The spatial distribution of particles in a dust cloud (the
variation in concentration throughout a dust cloud)
Oxygen concentration
Turbulence in the space or area
Characteristics of the ignition source (including
magnitude and level of energy)
Location of the ignition source in relation to the dust
cloud
Many more variables come into play for combustible dust incidents
than for scenarios involving flammable gases, flammable liquids, or
larger-sized flammable solids. The ignition of vapor-air mixtures,
especially at rest, is much more predictable and reproducible than the
ignition of combustible dust. Consequently, some mitigation methods
used to address combustible dust hazards are not straightforward.
Prescriptive requirements may not be reasonable or effective in such a
scenario.
Another factor involves whether and how to integrate current and
future national consensus standards into a regulatory scheme. One means
of doing so may be for OSHA to require compliance with various NFPA
standards, rather than to develop a government-unique standard. Some of
the issues with this approach are discussed earlier in section I(G) of
this notice. Another approach may be to reference NFPA standards as
acceptable compliance options.
OSHA must also consider the interrelationship of a combustible dust
standard and other OSHA standards that address different features of
the hazard, for example, the hazard communication, electrical, grain
handling, and other standards noted earlier in section I(F) of this
notice.
The information currently available indicates that the risk of
combustible dust explosions is considerable and that a single,
comprehensive standard addressing all of these hazards will likely
provide clarity for employers and increased safety for exposed workers.
OSHA is requesting information and comment from the public to evaluate
what regulatory action it should take to further address combustible
dust hazards within the general industry standards.
II. Request for Data, Information, and Comments
OSHA is providing the following questions to facilitate the
collection of needed information and to facilitate public comment on
relevant issues. OSHA invites commenters to respond to any questions
for which they have specific knowledge, data, or information,
regardless of their involvement with combustible dust, e.g., employer,
employee, consultant, researcher, fire or building code enforcement
official. Commenters also are encouraged to address any aspect of
combustible dust safety that they believe would assist the Agency in
considering appropriate regulatory action on the matter. OSHA requests
that commenters provide a detailed response to questions, including a
rationale or reasoning for the position taken, rather than simply
replying "yes" or "no." Also, relevant data that may be useful to
OSHA's deliberations, or that may assist it in conducting an analysis
of the impacts of future Agency actions, should be submitted. To assess
the costs, benefits, or feasibility of any possible regulatory
intervention, the Agency needs specific quantitative information on
various safety measures. Therefore, for those recommendations involving
specific interventions, any data in terms of costs and benefits
associated with the recommendation would be helpful. To assist it in
analyzing comments, OSHA requests that commenters reference the
question number to which they are responding.
A. Industry Background
OSHA is interested in determining the extent of combustible dust
hazards. The following questions address the extent of the hazards, and
provide a context in which to understand your answers to subsequent
questions.
1. What business are you in? What NAICS industry or industries are
you in?
2. How many employees do you have? How many are production
employees? How many employees work in areas where combustible dusts are
present? What types of jobs do they perform?
3. What is the area of your facility? What percentage of this area
has combustible dusts normally present? What percentage is subject to
possible fugitive dust accumulations?
4. What type or types of combustible dusts are present?
5. Would you expect other firms in your industry to have similar
combustible dusts hazards or are the products or processes that
generate combustible dust in your facility unusual for your industry?
Why?
B. Definition of Combustible Dust
No single, universally accepted definition of combustible dust is
available. Even among standards promulgated by the same standards-
developing organization, the definitions vary significantly. NFPA 654
and 655 define combustible dust in general terms without regard for
particle size. This approach recognizes that factors such as particle
shape, agglomeration, and other characteristics listed earlier in this
notice, can affect explosibility. Other standards (such as NFPA 61,
484, and 664) define combustible dust in terms of a minimum particle
size. The definition in previous editions of NFPA 654 (which may still
be used in some areas of the country) was also size-based.\19\
Furthermore, OSHA's grain standard uses a size-based definition for
"fugitive grain dust."
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\19\ The 2006 edition of NFPA 654 explains in Annex section
A.3.3.4 the reason that the previous size-based definition is no
longer used: "Dusts traditionally have been defined as a material
420 [micro]m or smaller (capable of passing through a U.S. No. 40
standard sieve). Combustible particulates with an effective diameter
of less than 420 [micro]m should be deemed to fulfill the criterion
of the definition. However, flat platelet-shaped particles, flakes,
or particles of fibers with lengths that are large compared to their
diameter usually do not pass through a 420 [micro]m sieve yet still
pose a deflagration hazard."
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Many different materials may form combustible dust, and several
laboratory tests are available to characterize them. Some of these
tests help determine a dust's basic explosibility. Other tests yield
results on the degree of explosibility; these tests are useful for designers
of built-in protective features or systems. In some cases, the hazards of certain
dusts are widely known (for example, wood dust). In these cases, basic
testing to determine whether the dust is explosive may not be
necessary. OSHA is interested in data on the extent to which different
materials are, or may form, combustible dust.
6. Do you determine whether a dust is considered a combustible dust
by reference to data, testing, or some other means? Please explain.
7. What additional tests do you conduct to determine the level of
combustibility of a particular dust?
8. Do you have any dusts that you assume to be combustible, and,
thus, preclude the need or expense of testing? If so, please indicate
what type of dust.
9. Certain definitions, in particular those definitions based on
particle size alone, would not cover some materials that can present an
explosion hazard in certain situations. Accordingly, identify any dusts
that can explode that would not be included in your definition. Would
your definition include some dusts for which explosions are very rare
or unknown? If so, which ones?
C. Hazard Recognition
The CSB report on its combustible dust hazard study, as well as the
investigative reports of specific combustible dust incidents discussed
above, show a pattern of employers and workers being either unaware of
the hazards posed by combustible dust, or of the seriousness of the
hazards. As a result, many workers were not adequately protected from
these hazards. Employers who have recognized the hazards were made
aware of them in a variety of ways. OSHA is interested in data on the
contributions of in-house experts, outside consultants, insurance
representatives, and local or State code authorities in improving
awareness of the hazard.
10. How did you become aware that you had combustible dust present
in your facility?
11. Who is responsible for determining if a dust is combustible?
What expertise do they have?
12. How do you determine if dust is combustible? Do you use
published data, and if so, from what source? Do you sample dust for
laboratory testing, and if so, how often? Do you rely on labels or data
sheets, including MSDSs, developed by others? Do suppliers provide you
with information related to combustible dust? Please explain.
13. To what extent do the local code authorities, insurance
representatives, or other outside experts determine the presence of
combustible dust in your facility?
D. Hazard Assessment
Hazard assessments are systematic approaches to evaluating a hazard
and selecting control or mitigation methods. CSB's report on its
combustible dust hazard study recommends hazard assessments as
necessary for the mitigation of combustible dust hazards. It should be
noted that NFPA 654 refers to a hazard assessment as a "Process Hazard
Analysis." In addition to information about how employers perform
hazard assessments, OSHA is also interested in the extent to which
experts (both external and on-staff) are involved in hazard
assessments.
14. Do you conduct assessments of combustible dust hazards? How
often? What assessment method do you use? Describe the information you
use in performing the assessment, as well as the information the
assessment yields and how you use this information.
15. On whom do you rely for technical assistance when performing
the assessment? In-house staff, local/State authorities, insurance
representatives, or consultants?
16. How do you decide when outside expertise or assistance is
necessary? How do you assess the capability of outside experts?
17. Are your employees involved in the hazard assessment? Does
their involvement improve the assessment? Does their involvement
improve their understanding of the hazard and its mitigation?
E. Hazard Communication and Training
OSHA's Hazard Communication Standard (HCS), 29 CFR 1910.1200,
comprehensively addresses the evaluation of the potential hazards of
chemicals and the communication of hazard information to workers.
Regarding dusts and other particulates, as with all chemicals covered
by the HCS, a hazard evaluation must be conducted, taking into
consideration all discernible hazards, including explosibility. It is
incumbent upon manufacturers and importers to provide information on
the potential for, and control of, combustible dusts.
The HCS standard has three main components that are essential to
the effective functioning of a program. First, chemical manufacturers
and importers must review available scientific evidence concerning the
physical and health hazards of the chemicals they produce or import to
determine if they are hazardous. This procedure is called a hazard
determination or hazard evaluation. Second, for every chemical found to
be hazardous, the chemical manufacturer or importer must develop
Material Safety Data Sheets (MSDSs) and container labels to be
transmitted to downstream users of the chemicals. Employers are
required to maintain an MSDS in the workplace for each hazardous
chemical that they use. Third, all employers must develop a written
hazard communication program and provide information and training to
employees about the hazardous chemicals in their workplace.
Regarding combustible dusts, anticipated operations, uses, and
downstream material processing that generate dusts should be considered
normal conditions when using a substance. These conditions include
operations and uses such as abrasive blasting, cutting, grinding,
polishing, or crushing materials; conveying, mixing, sifting, or
screening dry materials; and the build-up of dried residue from
processing wet materials.
The HCS requires chemical manufacturers and importers to develop an
MSDS for each hazardous chemical they produce or import. The following
MSDS requirements are applicable to combustible dust hazards: Chemical
and common names of the hazardous chemical and all ingredients
determined to present a physical hazard, physical and chemical
characteristics of the hazardous chemical, any generally applicable
precautions for safe handling and use, any generally applicable control
measures, date of MSDS preparation or last revision, and the name,
address, and telephone number of the responsible party preparing the
MSDS.
During its combustible dust study, CSB reviewed MSDSs of 140 known
substances that produce combustible dusts, and found that information
regarding potential combustible dust hazards was poorly or inadequately
transmitted to employers and workers; according to this report, 41
percent of the MSDSs reviewed in the CSB study did not warn users about
potential explosion hazards. Of the remaining 59 percent of MSDSs
sampled, most of the information was not stated in a place or manner
clearly recognized by employees, or not specific to hazards related to
combustible dusts. The CSB concluded that many of the MSDSs did not
identify the potential for combustible dust explosions that could
reasonably have been anticipated during downstream material processing.
Training is also a critical component of any program to control
combustible dust and prevent fires and explosions. Employees need to
understand the hazards, how to prevent the hazards, and what to do in the
event of a fire or explosion.
The following questions address MSDSs and training related to
combustible dust hazards.
18. Do the MSDSs you develop or use identify the risks associated
with combustible dust hazards? Do they list mitigation measures? Are
you aware of MSDSs that should identify combustible dust as a hazard
and do not? If so, please explain.
19. Do you communicate information on the risks of, and controls
for, combustible dust hazards to your employees as a part of your
hazard communication program?
20. Do you train your employees on the hazards of combustible dust
and its mitigation? Do you also provide refresher training? What is
covered in each type of training that you provide? How many of your
employees receive each type of training that you provide? How many
hours of training is provided and at what frequency (on hire, annually,
as needed)? Who provides the training? What are their qualifications?
Do you use standardized training materials (such as films, books, and
computer classes)?
21. Do you have any means of determining if employees understand
the training? Do you have any means of determining if employees are
applying the training? If so, describe these means.
F. Consensus, Industry, and Insurance Standards
Under the OSH Act, OSHA must consider the provisions of national
consensus standards, such as those promulgated by NFPA, in its
rulemaking efforts. In addition to this mandate, OSHA may consider
standards that are not developed using the consensus- standards process
when determining appropriate protective measures for employees. The
following questions refer to these standards.
22. Do you follow the provisions in NFPA standards for combustible
dust? If so, which standards? Is this use voluntary, or based on
mandates by local authorities, insurance carriers, or other entities?
Do you have any difficulty in using the NFPA standards because of
conflicting definitions, varying requirements, secondary references to
other standards, or any other reason? If so, describe these
difficulties.
23. Do you use FM Global Property Loss Prevention Data Sheet 7-76,
Prevention and Mitigation of Combustible Dust Explosions and Fires, as
an aid in determining how to mitigate the hazards of combustible dust?
Is this use voluntary or mandated by your insurance carrier?
24. Are there any other standards or guides you use to address the
hazards of combustible dust? If so, please indicate which ones, or
describe them.
G. State and Local Codes
NFPA standards carry the force of law when adopted by a
jurisdiction (Federal, State, county, or municipal); these standards
also can be mandated by an insurance company or other entity. In some
cases, even when not mandated, employers comply with these standards
(or portions of them) as a matter of policy. Many State fire codes
contain mandatory references to NFPA's combustible dust-related
standards either directly, or by the adoption of a model fire code. The
two model fire codes used in this country (i.e., International Code
Council's International Fire Code and NFPA's Fire Code) both mandate
compliance with NFPA's combustible-dust-related standards. Despite the
existence of consensus and insurance standards, and State fire codes,
major incidents continue to occur, as described earlier in this notice.
The CSB's 2006 report on its combustible dust hazard study
concluded that State and local enforcement of NFPA standards was
inadequate to protect workers. The reasons found include limited
resources, insufficient training, and enforcement efforts that
concentrate on facilities other than industrial facilities.
OSHA's National Emphasis Program for combustible dust has resulted
in many employers abating combustible dust hazards in their facilities.
Some employers voluntarily upgraded their facilities, procedures, and
policies based on outreach and guidance material made available by a
variety of organizations (including OSHA) or in response to the
publicity surrounding major dust explosions. These efforts increased
worker and employer awareness of the benefits of complying with NFPA
standards. Nevertheless, it is difficult to project trends for hazards
that result in infrequent, major incidents such as combustible dust
explosions. Because of the variability of the many components required
for a significant combustible dust explosion, facilities can operate
for decades without an incident, yet suffer a catastrophic event after
a slight change in conditions. The following questions address
enforcement issues involving combustible dust.
25. Does the fire or building code (State, local, or other) in your
area specifically address the hazards of combustible dust? If so, how?
26. Has your facility been inspected by State or local authorities?
Is this a regular occurrence? If so, at what frequency? Were these
inspections initiated by the authorities, or did you take the
initiative to contact them? Did the inspections include combustible
dust hazards? Did the inspection officials have expertise on
combustible dust hazards? What action did you take as a result of State
or local inspections?
27. Do you know if State or local enforcement efforts have been
effective in controlling combustible dust hazards? If you have
information on any studies of this issue other than the CSB's study
(for example, studies conducted by insurance organizations, code
authorities, trade associations, consultants, or unions), please
provide information on them.
H. Engineering Controls
Various methods of controlling occupational hazards fall into a
hierarchy in order of their effectiveness. A typical hierarchy
(beginning with the most effective method) is:
Elimination.
Substitution.
Engineering controls.
Administrative controls.
Personal protective equipment.
Administrative controls include work practices, personnel
scheduling, operational procedures, and equipment maintenance.
Engineering controls are fixed measures that are built into a facility
or processing equipment to either remove a hazard (i.e., preventing it
from occurring) or to minimize the effects of an incident (after a fire
or explosion has begun). OSHA believes that, for combustible dust
hazards, these two types of engineering controls may belong at
different levels in the hierarchy. Those engineering controls that
prevent the occurrence of an incident, hereinafter referred to as
"primary engineering controls," belong where they are normally seen
in the hierarchy; ahead of administrative controls. Those engineering
controls that minimize deaths, injuries, or damage after a fire or
explosion has begun, hereinafter referred to as "secondary engineering
controls," may be more appropriately placed in the hierarchy after
administrative controls. Therefore, OSHA has grouped the questions in
this section into two categories: (a) Primary engineering controls, and
(b) secondary engineering controls.
Collectively, primary and secondary engineering controls often
include features of building design, processing systems, ventilation systems,
protective systems, and alarm systems. In NFPA 654, these provisions are not
retroactive; that is, facilities, equipment, structures, or installations that
existed or were approved prior to the standard becoming effective may remain as
is. While retrofitting of most equipment is not mandated under this standard, it
allows the authority having jurisdiction to require retrofitting of
equipment or features in situations presenting an unacceptable degree
of risk.
If OSHA were to incorporate provisions for engineering controls in
a combustible dust standard, it would need to address whether any of
these controls should be (1) retrofitted for all existing facilities
immediately, (2) mandated after a specified date or period (i.e., a
delayed effective date), or (3) required only for facilities built
after a specified date or period (i.e., a "grandfather" clause). The
Agency is, therefore, asking the following questions regarding
engineering controls.
28. Do your facilities or equipment have any of the following
primary engineering controls to mitigate combustible dust hazards? If
so, describe in detail where they are installed and how they function
to mitigate combustible dust hazards.
a. Features to prevent escape of dust into unwanted areas.
b. Features to prevent the accumulation of dust on surfaces.
c. Oxygen concentration reduction.
d. Dilution with noncombustible dust.
e. Foreign material (such as tramp metal) separation devices.
f. Monitoring and alarms for abnormal conditions.
g. Automatic interlocks, shutoffs, or overflow systems.
h. Manual emergency controls.
i. Lightning protection systems.
j. Features to mitigate the hazards of process heating systems.
k. Features to mitigate the hazards of comfort heating systems.
l. Features to mitigate the hazards of hot surfaces.
m. Class II electrical equipment and wiring.
n. Other mitigation features or engineering controls designed or
built into your facility or processing equipment to prevent the
occurrence of fires or explosions.
29. Do your facilities or equipment have any of the following
secondary engineering controls to mitigate combustible dust hazards? If
so, please describe in detail where they are installed and how they
function to help mitigate combustible dust hazards.
a. Air-material separators (dust collection systems)
b. Segregation with physical barriers.
c. Separation by distance.
d. Fire-resistant construction.
e. Deflagration pressure containment.
f. Deflagration suppression systems.
g. Automatic fire suppression systems.
h. Manual fire suppression equipment.
i. Deflagration venting.
j. Dust retention and flame arresting devices.
k. Relief valves or devices.
l. Abort gates or dampers.
m. Isolation devices to preclude deflagration propagation.
n. Evacuation alarm systems.
o. Fire, heat, smoke, flame, or spark/ember detection systems.
p. Other mitigation features or engineering controls designed or
built into your facility or processing equipment to limit deaths,
injuries, or damage after a fire or explosion has occurred.
30. Do you feel that secondary engineering controls should be in
the preferred hierarchy of controls after administrative controls? Why
or why not? Please describe incidents where secondary engineering
controls were effective or ineffective.
31. How much did each fixed feature cost to install? Are there any
special maintenance or operating costs associated with these features
(such as energy costs, waste disposal costs, maintenance activities
such as clean up)? Are there any other routine costs associated with
these measures?
32. How did you decide which of these features to provide in your
facility? Were these features installed during the initial construction
of the facility, or retrofitted at a later time?
I. Administrative Controls
Typically, an OSHA standard includes provisions for administrative
methods and work practices to control or mitigate a hazard. These
provisions include operational procedures, portable equipment,
equipment maintenance, or personal protective equipment. In NFPA 654,
these types of provisions are retroactive, which means they apply to
all facilities, both new and existing. The following questions address
the use of administrative and work practice controls in your facility.
33. Does your facility have any methods that prevent or limit the
escape of dust? Please describe these methods.
34. Do you have a program or policy specifically for cleaning
surfaces to remove accumulated fugitive dust? What surfaces does this
program cover? What is the frequency with which you remove dust from
surfaces? Do you inspect hidden and non-work areas, such as ventilation
systems, product or input storage areas, concealed spaces, areas above
suspended ceilings, beams, and ledges, for fugitive dust accumulation?
35. Do you have criteria or measures for what amount or level of
fugitive dust accumulation is tolerable (such as a specific depth over
a given area, inability to discern underlying color)? Please describe
these criteria and measures.
36. Do you use cleaning methods that preclude dust disbursal? Which
methods do you use, and under what conditions? What methods do you
prohibit, and why?
37. Do workers' assignments, in whole or in part, involve cleaning
dust from surfaces? How many workers perform this task, and how many
hours per week do they spend on dust removal? Can the cleaning be done
with minimal interruption of the facilities' operations?
38. Do you implement ignition controls for any of the following
ignition sources for areas where combustible dust may be present? If
so, indicate which sources and provide details. Did you consult with
your operational employees in developing these programs or policies?
How do you assure that your programs or policies are followed by all
relevant parties?
a. Control of static electricity.
b. Use of cartridge-actuated tools.
c. Control of open flames and sparks (including cutting, welding,
grinding, chipping).
d. Control of smoking.
e. Restrictions for hot surfaces.
f. Use of powered industrial trucks (EX or DX designation).
39. Do you have a program in place for the maintenance and testing
of fixed facilities, equipment, structures, or systems? If so, please
describe the program.
40. Do you have or use any personal protective equipment specific
to combustible dust hazards? If so, please describe the equipment, and
the reasons for its use.
41. Are any of your administrative or work practice programs or
policies written? If so, please provide a copy of these written
documents.
J. Emergency Response
Fighting combustible dust fires, or fires near combustible dust
hazards, presents unique hazards. If done incorrectly, risk of death
and injury may rise for both employees and firefighters. For example,
opening a containment system or using straight-stream nozzles can cause
dispersion of dust, which can then become the fuel for an initial or
secondary fire or deflagration. The following questions address
emergency-response procedures in your facility.
42. Do you provide facility information to industrial fire brigades
or other emergency responders for the purpose of assisting their
efforts to respond to fires or explosions? If so, please describe the
information you provide to them.
43. Do you provide training to employees, industrial fire brigades,
or other emergency responders on the hazards of fighting fires in
combustible dust-producing facilities? If so, respond to the following
questions, and provide details and explanation. Do you train these
groups on combustible dust hazards and their mitigation? Do you also
provide refresher training? What is covered in this training? How many
people receive this training? How many hours of training is provided
and at what frequency (on hire, annually, as needed)? Who provides the
training? What are their qualifications? Do you use standardized
training materials (such as films, books, and computer classes)? Do you
have any means of determining if attendees understand the training? Do
you have any means of determining if attendees apply the training after
they receive it? Please describe any instances where the training
provided affected the outcome of an incident.
K. Investigation of Incidents
Much can be learned from combustible dust fires and explosions. In
some cases, frequent minor incidents failed to garner the attention of
employers, leading to complacency in the workplace. In other cases,
minor incidents shielded the catastrophic potential of combustible dust
hazards.
Many of the provisions included in the consensus standards
addressing combustible dust have been refined over the years based on
loss experience. Potentially, even more can be learned by studying
incidents in which protective features effectively prevented death or
injury, or incidents considered near misses. Some possible
characterizations of near misses are situations under which a
combustible dust cloud nearly ignited, a fire caused no deflagration or
explosion, or a deflagration or explosion resulted in no injury or
death. The following questions address your facility's responses to
combustible dust fires, explosions, and near misses.
44. Have you had any combustible-dust-related fires, explosions, or
near misses? Is so, describe these incidents in detail, and indicate
what changes were implemented to prevent a reoccurrence. How do you
define or characterize a near miss?
45. Are combustible-dust-related fires, explosions, or near misses
investigated? If so, indicate how thoroughly, who performs them, and
what professional qualifications they have. Do you document
investigation results? If so, please provide examples of such
documentation.
46. Does such a fire, explosion, or near miss cause a new hazard
assessment to be conducted? Do these incidents cause you to review your
engineering or administrative controls?
L. Regulatory Approach
OSHA is considering a variety of regulatory approaches to eliminate
or mitigate combustible dust hazards. Your comments on the following
issues will help OSHA decide how best to protect workers effectively
from combustible dust hazards.
47. OSHA recognizes that the risk from combustible dust hazards
varies with the type of material involved and the conditions present,
the particular processes used at a facility, and the number of workers
exposed. These hazards exist in facilities ranging from a woodworking
shop with one employee to a large manufacturing plant with thousands of
workers. Should OSHA scale its requirements to be more or less
restrictive depending on either the size of, or type of dust present
in, the facility? How should this scaling be done (i.e., how should the
provisions of a standard be applied to different facilities)? Are there
situations or conditions that should limit the provisions that apply?
If so, please explain.
48. Given the various definitions in the consensus standards, how
should OSHA define combustible dust--by minimum particle size, without
regard for particle size, or should the definition vary for the type of
dust? Provide the technical basis for your response.
49. Data indicates that mineral dusts (such as silicates,
sulphates, nitrates, carbonates, phosphates, cement, salt, gypsum,
sand, and limestone) are not explosible. Should OSHA exclude mineral
dusts or any other dust from coverage? If so, which dusts? Please
provide the technical data substantiating the lack of explosibility.
50. Some dusts (such as wood dust) are widely understood to be
combustible, and are explosible under a wide range of conditions.
Should OSHA consider certain dusts explosible under any conditions,
thereby precluding the need for testing? Alternatively, should OSHA
permit employers to make this determination? If so, for which types of
dust? Please explain your responses.
51. The NFPA combustible-dust-related standards have some similar
provisions, but also have some provisions that vary for different types
of dusts. Other NFPA standards have provisions that apply only to
specific dusts. Should an OSHA standard cover different types of dusts
separately, together, or in some other manner? Please explain your
response.
52. The approach suggested by the CSB and others contains many of
the elements in OSHA's Process Safety Management (PSM) Standard. Should
an OSHA standard take an approach similar to the PSM Standard, e.g., by
requiring the development and implementation of a site-specific plan
tailored to the facility and hazards in question? Please provide a
rationale for your response.
53. NFPA 654 contains a provision for combustible dust hazard
assessment, which helps refine the actions required for adequate safety
under the specific conditions present in a facility. OSHA recognizes
that this approach may not be necessary for all types and sizes of
facilities. For example, a small furniture shop may be able to safely
operate under a fixed set of requirements for the well-understood
hazards of wood dust. Should every provision of an OSHA combustible
dust standard be addressed in a hazard assessment, or just provisions
involving engineering controls? Should the hazard assessment vary
according to the size or type of facility? Please explain your
response.
54. It has been suggested that OSHA incorporate NFPA standards by
reference to address combustible dust hazards. The Agency is concerned
with a number of issues regarding this approach. These concerns
include, but are not limited to:
a. The scope of NFPA standards exceeding OSHA's mandate to protect
only employees.
b. The multitude of mandatory primary references, secondary
references, and other subordinate references in each NFPA standard that
could result in an unnecessary burden on employers.
c. The differences between the various NFPA combustible-dust-
related standards.
d. The frequent updating of standards by NFPA, making the OSHA
standard outdated.
e. The limited availability of older editions of NFPA standards.
f. The difficulty involved in readily updating the consensus
standards referenced in an OSHA combustible dust standard to the
current or most recent edition of the consensus standards.
g. The fact that OSHA cannot legally update NFPA or other consensus
standards used in its rules by referring to the "current" or "most
recent" edition of the consensus standards.
How do you think the Agency should make use of NFPA standards in a
prospective OSHA standard? If the NFPA standards are not directly
incorporated by reference into the OSHA standard, would it be
appropriate for the OSHA standard to reference NFPA standards as
compliance alternatives (e.g., if an employer complies with the
referenced NFPA standard applicable to an operation, OSHA would deem
the employer to be in compliance with the applicable provision of the
OSHA standard)?
55. Outreach efforts (both public and private), employer awareness,
and OSHA's enforcement have increased in response to various
combustible dust incidents over the last decade. As a result, many
employers continue to upgrade their facilities and update their
operating procedures to prevent and control combustible dust hazards.
Would an OSHA combustible dust standard increase employee safety beyond
the level already attained through current Federal efforts, State and
local requirements, and voluntary standards? What approach would most
effectively increase the safety of employees? Please provide a
rationale for your response.
56. In 2003, OSHA concluded in its regulatory review that no
significant changes were needed to OSHA's standard on Grain handling
facilities at that time. Are any revisions needed to the portions of
this standard that address fires and explosions? Are revisions to this
standard necessary to harmonize it with the treatment of other dusts?
Should the existing provisions of the standard that address fires and
explosions be covered under a combustible dust rule? If OSHA retained
the standard and issued a combustible dust standard that applied to
other facilities and processes, would portions of your plant be covered
by both standards? If so, would this present a problem? Please explain
your response.
57. OSHA anticipates that administrative and work practice controls
would be included in a combustible dust standard. For instance, several
OSHA standards already address the accumulation of fugitive combustible
dust, but do not address the escape of dust. Some ignition sources are
covered under current OSHA standards (such as electrical and powered
industrial trucks), but other, easily controlled ignition sources,
would likely be addressed in a prospective OSHA combustible dust
standard (such as open flames, sparks, hot surfaces, static
electricity, tools, and smoking). Engineering controls can be more
costly and take longer to implement than administrative controls.
Should an OSHA combustible dust standard have requirements for
engineering controls to control fugitive combustible dust? Which
engineering controls should or should not be required, and under what
circumstances? Should OSHA require retrofitting of engineering
controls, and if so, which controls? What time period should OSHA allow
for retrofitting? What are the costs associated with retrofitting these
controls?
58. Workers are often in the best position to understand how
processes work and the characteristics of the materials involved.
Workers also may be in the best position to see how variations in
procedures or equipment can affect their safety. Should operational
employees participate in the development of engineering and
administrative controls? Will this participation improve their safety?
Please explain your response.
59. Facilities, processes, and materials are subject to change over
time. These changes can affect potential hazards, and, thereby, the
means used to mitigate those hazards. If these changes are not examined
to determine if corresponding changes in protection or prevention are
necessary, worker safety could be decreased. Should change management
be a component of an OSHA standard? Why or why not?
60. A fire, explosion, or near-miss, could indicate that
improvements are necessary to provide an adequate level of employee
safety. Improvements may depend on the incident's severity or
consequences. Should investigations of fires or explosions be a part of
an OSHA combustible dust standard? Should a fire or explosion be
classified for reporting purposes in terms of its severity, effect,
size, or duration? If so, provide details. Should investigations and
reporting of near-misses be a part of an OSHA standard? Please explain
your response.
61. Should an OSHA combustible dust standard address the hazards of
fighting fires in combustible-dust-producing facilities? If so, should
the standard address fire fighting by designated employees, an
employer's industrial fire brigade, or other emergency responders? In
your response, provide details on hazards specific to fighting fires in
or near combustible dust.
M. Economic Impacts and Benefits
As part of the process of developing a standard, OSHA must estimate
the costs, economic impacts, and benefits of the standard. OSHA also
analyzes the benefits of its standards in terms of reduced deaths,
injuries, and property loss. The following questions will provide OSHA
with needed economic impact and benefits information.
62. What are the potential economic impacts associated with the
promulgation of a standard specific to the hazards of combustible dust?
Describe these impacts in terms of benefits from the reduction of
incidents and injuries; effects on revenue and profit; and any other
relevant impact measure. If you have any examples of estimates of the
costs of controlling combustible dust hazards, please provide them.
63. What changes, if any, in market conditions would reasonably be
expected to result from issuing a standard on combustible dust?
Describe any changes in market structure or concentration, and any
effects on services, that would reasonably be expected from issuing
such a standard.
64. Would a comprehensive OSHA standard on combustible dust reduce
fire and explosion hazards? How would an OSHA standard address any
noncompliance problem (such as, noncompliance with the housekeeping
standard or the GDC)?
N. Impacts on Small Entities
In developing a standard, OSHA must determine whether it will have
a significant impact on a substantial number of small businesses. If
the standard has such impacts, OSHA is required to develop a regulatory
flexibility analysis and assemble a Small Business Regulatory
Enforcement Fairness Act (SBREFA) Panel prior to publishing a proposal.
Regardless of the significance of the impacts, OSHA seeks ways of
minimizing the burdens on small businesses consistent with OSHA's
statutory and regulatory requirements and objectives. OSHA has
preliminarily determined that 330,000 small firms owning 351,000
establishments and employing 6.5 million employees are in industries
that experienced combustible dusts fires or explosions in the past.
65. How many, and what type of small firms, or other small
entities, have combustible dust hazards, and what percentage of their
industry (NAICS code) do these entities comprise?
66. How, and to what extent, would small entities in your industry
be affected by an OSHA standard regulating combustible dust? Do special
circumstances exist that make controlling combustible dust more difficult
or more costly for small entities than for large entities? Describe these
circumstances.
O. Compliance Assistance
As indicated above, OSHA has provided outreach and guidance
documents, and training, related to combustible dust hazards. Through
the following questions, the Agency seeks information on the
effectiveness and benefits of its outreach, guidance, and training
efforts, as well as suggestions for future products.
67. Are you familiar with any of the following guidance and
outreach products OSHA has produced? Which of these products have you
used as an aid in determining what to do about combustible dust in your
facility?
a. Safety and Health Information Bulletin--Combustible Dust in
Industry: Preventing and Mitigating the Effects of Fire and Explosions.
b. Web site Safety and Health Topics Page - Combustible Dust.
c. Hazard Alert Fact Sheet - Combustible Dust Explosions.
d. Poster - Combustible Dust - Does your company or firm
process any of these products or materials in powdered form?
68. What types of materials, products, or outreach would assist you
and employees in addressing combustible dust hazards? Do small
businesses have special needs with respect to the form or content of
such materials? Would dust-specific or industry-specific materials be
useful?
69. Do you prefer paper publications such as booklets, fact sheets,
and quick cards, or electronic tools such as OSHA safety and health
topics pages and eTools?
III. Public Participation
Submit comments in response to this document by (1) hard copy, (2)
fax transmission (facsimile), or (3) electronically through the Federal
Rulemaking Portal. Because of security-related procedures, a
significant delay may occur in receiving comments by regular mail.
Contact the OSHA Docket Office at (202) 693-2350 for information about
security procedures concerning the delivery of materials by express
delivery, hand delivery, and messenger service.
All comments and submissions are available for inspection and
copying at the OSHA Docket Office at the Technical Data Center, Room N-
2625, U.S. Department of Labor, 200 Constitution Ave., NW., Washington,
DC 20210. Comments and submissions are also available at http://www.regulations.gov.
OSHA cautions commenters about submitting personal information such as
Social Security numbers and birth dates. Contact the OSHA Docket Office at
(202) 693-2350 for information about accessing materials in the docket.
Electronic copies of this Federal Register notice, as well as news
releases and other relevant documents, are available at OSHA's Web
page: http://www.osha.gov/index.html.
IV. Authority and Signature
This document was prepared under the direction of Jordan Barab,
Acting Assistant Secretary of Labor for Occupational Safety and Health,
U.S. Department of Labor, pursuant to sections 4, 6, and 8 of the
Occupational Safety and Health Act of 1970 (29 U.S.C. 653, 655, 657),
29 CFR part 1911, and Secretary's Order 5-2007 (72 FR 31160).
Jordan Barab,
Acting Assistant Secretary of Labor for Occupational Safety and Health.
[FR Doc. E9-25075 Filed 10-20-09; 8:45 am]
BILLING CODE 4510-26-P
