[December 24, 2009]
Mr. Rick Smithpeter
Cooperative Mutual Insurance Company
3905 S. 148th Street
Omaha, Nebraska 68114
Dear Mr. Smithpeter:
Thank you for your October 15, 2008, letter to the Occupational Safety and Health Administration (OSHA), in which you describe the operation of a sweep auger inside a grain storage bin. Your October 15th letter was in response to OSHA's reply dated September 29, 2008 (enclosed). Please note that this letter constitutes OSHA's interpretation, only of the requirements discussed, and may not be applicable to any questions not delineated within your original correspondence. Your paraphrased questions and our responses are provided below.
Background: You state in your letter that a sweep auger is a portable unguarded screw auger attached to a pivot that circles the perimeter of the storage bin and conveys grain into a center sump(s) located in the bin floor. In order for the sweep auger to work properly, the operator must regularly make adjustments to the device inside the bin. You also state that, by design, a sweep auger cannot be guarded and that there is no room between the bin wall and the end of the sweep auger that would allow a worker to be positioned so that he or she is not in the path of the auger. You contend that the use of a rope positioning system, which would prevent a worker from being exposed to the hazards presented by the moving machinery of the sweep auger, would be extremely dangerous.
OSHA's standard at 29 CFR 1910.272 includes specific requirements addressing safety hazards associated with grain handling facilities. Section 1910.272(g) addresses entry into grain storage structures, including bins, tanks and silos. The exception in Section 1910.272(g) states: "entry through unrestricted ground level openings into flat storage structures in which there are no toxicity, flammability, oxygen-deficiency, or other atmospheric hazards is covered by paragraph (h) of this section."
Section 1910.272(h) includes requirements for entry into flat storage structures. Section 1910.272(c) defines a "flat storage structure" as "a grain storage building or structure that will not empty completely by gravity, has an unrestricted ground level opening for entry, and must be entered to reclaim the residual grain using powered equipment or manual means." Flat storage structures with no atmospheric hazards that are entered at ground level through regular or large-sized doorways or openings are covered by paragraph (h).
Entry into grain storage bins, tanks, silos, and grain storage structures including flat storage structures at or above the grain level or with atmospheric hazards are covered by paragraph (g). Based on the above OSHA requirements and the information that you provided in your letter, it appears that your storage structure is covered by Section 1910.272(g).
Question 1: Can an unguarded sweep auger be in operation (energized) in a grain storage bin while a worker is inside the bin?
Response 1: No. OSHA's standard at 29 CFR 1910.272(g)(1)(ii) states:
All mechanical, electrical, hydraulic, and pneumatic equipment which presents a danger to workers shall be deenergized and shall be disconnected, locked-out and tagged, blocked-off, or otherwise prevented from operating by other equally effective means or measures. [emphasis added].
Also, with respect to entry into flat storage structures, covered by paragraph (h), Section 1910.272(h)(2)(i) provides:
Whenever an employee walks or stands on or in stored grain or grain products of a depth which poses an engulfment hazard, all equipment which presents a danger to the employee (such as an auger or other grain transport equipment) shall be deenergized, and shall be disconnected, locked-out and tagged, blocked-off, or otherwise prevented from operating by other equally effective means or methods.
We note that workers face a number of hazards whenever they enter a grain storage bin. For example, workers may face an engulfment hazard inside a storage bin when grain is being drawn off to the bottom by an auger. Flowing or moving grain produced from an auger might also result in a tripping or slipping hazard that could cause the worker to accidentally fall into the machinery. In addition, a danger may exist to workers from energized equipment when grain is not flowing or moving. For example, a worker who is required to regularly adjust an unguarded moving auger, in order for it to work correctly, may slip, trip, or fall and be placed in the path of the moving auger.
OSHA's standards clearly provide that if a danger to a worker exists, all equipment inside grain storage facilities must be disconnected, locked-out and tagged, blocked-off or prevented from operating by other means or methods. The standards do provide some flexibility to employers for ensuring that equipment is not operating and does not present a danger to workers inside the storage structure. However, based on the additional information provided in your October 15th letter, OSHA is not aware of any effective means or method that would protect a worker from the danger presented by an unguarded sweep auger operating inside a grain storage structure. Accordingly, unless the employer can eliminate all hazards presented by an energized unguarded sweep auger, operating such a device with workers inside a grain storage structure would be in violation of Section 1910.272(g)(1)(ii) or Section 1910.272(h)(2)(i).
Question 2: If workers follow the requirements in 29 CFR 1910.23(a)(5), can they work in the bin while the sump(s) is not guarded?
Response 2: Yes. OSHA's standard at 29 CFR 1910.23(a)(5) states:
Every pit and trapdoor floor opening, infrequently used, shall be guarded by a floor opening cover of standard strength and construction. While the cover is not in place, the pit or trap shall be constantly attended by someone or shall be protected on all exposed sides by removable standard railings.
The standard sets forth the general rule that every pit and trap door floor opening, infrequently used, must be guarded. However, the standard also includes an exception to the general rule so that workers can work near an uncovered floor opening if, in relevant part, the opening is constantly attended by someone. As a result, a worker may work inside the bin when the sump hole is not guarded as long as a second worker is constantly attending the opening. You must note, however, that when workers are conducting work inside storage bins within the parameters of Section 1910.23(a)(5), employers must still comply with all other applicable OSHA standards, including 29 CFR 1910.272(g)(1)(ii) (e.g., Lockout/Tagout).
Question 3: Given the answers to the two questions above, and not including the use of lockout/tagout of energized equipment, guarding of the sweep auger, and providing gates or guarding on the sump(s), can OSHA provide me with a method or procedure for removing grain from flat bottom grain bins?
Response 3: Please keep in mind that OSHA does not approve, endorse, or recommend any particular procedure for removing grain from flat bottom grain bins. The final determination of compliance with OSHA's standards must take into account all factors pertaining to the use of sweep augers and other such equipment. This must include an evaluation, through direct observation, of worker work practices and all conditions of use in the workplace. Therefore, under the Occupational Safety and Health Act of 1970, only the employer is responsible for compliance with the Act and for the safe use of any product, including the use of sweep augers by their workers.
Thank you for your interest in occupational safety and health. We hope you find this information helpful. OSHA requirements are set by statute, standards, and regulations. Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations. This letter constitutes OSHA's interpretation of the requirements discussed. Note that our enforcement guidance may be affected by changes to OSHA rules. Also, from time to time we update our guidance in response to new information. To keep apprised of such developments, you may consult OSHA's website at http://www.osha.gov. If you have any further questions, please feel free to contact the Office of General Industry Enforcement at (202) 693-1850.
Richard E. Fairfax, Director
Directorate of Enforcement Programs