Categories: OSHA

By Amanda R. Strainis-Walker and Eric J. Conn

The roller coaster ride that has been OSHA’s enforcement policy in connection with work inside grain bins with energized sweep augers has taken another major turn.  After decades of employees working inside grain bins with sweep augers, a string of recent, somewhat confusing, Interpretation Letters issued by OSHA effectively banned the practice outright.  Now, a groundbreaking settlement of an OSHA case against an Illinois grain company became a Final Order of the OSH Review Commission in January, and that settlement renewed the industry’s right to work inside grain bins with energized sweep augers, and provided real clarity as to the conditions that OSHA considers to be acceptable for that work.

Sweep Augers

A sweep auger is a mechanism that attaches to a pivot point in the center of a flat-bottom grain bin, and then travels at very slow speeds in a circle around the bin, pulling grain from the perimeter of the bin towards a floor sump in the center of the bin by a helical screw blade called a flighting, where the grain exits to another conveying system.  Generally, one or more workers will be positioned inside the bin behind the sweep auger to make regular adjustments to the auger to keep it advancing on track, and also to manually sweep grain not captured by the auger.

By design, a sweep auger is typically guarded from accidental contact on the top and backside, but it cannot be guarded on the front, or the flighting of the auger would not be able to contact the grain, and therefore, would not convey grain towards the center sump.  In other words, the basic functionality of a sweep auger would be nullified if it were guarded on all sides.

The Grain Standard

The legal landscape about the use of sweep augers with employees inside grain bins has had many throughout the Ag Industry confused for years.  Part of the confusion dates back to the original implementation of the Grain Handling Standard (29 C.F.R. § 1910.272).   The final Grain Standard, which was published in 1987, did not include any provision to address the use of sweep augers or the conditions in which an employee may work inside a grain bin with an energized sweep auger.  The final rule did, however, include a general requirement about equipment inside grain bins at 1910.272(g)(1)(ii):

"All mechanical, electrical, hydraulic, and pneumatic equipment which presents a danger to employees inside grain storage structures 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."

Varying informal interpretations by OSHA about the language in the Standard: “which presents a danger” and “other equally effective means or methods,” resulted in inconsistent enforcement by OSHA in connection with sweep augers over the years.  A series of formal OSHA Interpretation Letters beginning in 2008, however, changed that landscape.

OSHA’s Sweep Auger Interpretation Letters

Around the same time that OSHA began to scrutinize the grain industry following a rash of engulfment incidents inside grain bins, OSHA also began to focus more attention on the issue of potential employee entanglement in the moving parts of sweep augers.  That attention was spurred in part by a letter to OSHA from an insurance agent seeking a formal interpretation of requirements related to grating/guarding on sumps inside grain bins with sweep augers.

The insurance agent’s letter described a scenario in which an employer required employees to maintain a distance of at least six feet behind a partially-guarded or unguarded sweep auger.  In a September 29, 2008 Interpretation Letter from OSHA responding to the insurance agent’s request, OSHA linked 1910.272(g)(1)(ii) to the use of sweep augers, and expressed the position that employees were prohibited from being inside grain bins with energized sweep augers unless the employer could demonstrate that appropriate protections were provided to prevent employees from exposure to the hazards of the moving machinery.  OSHA further stated that completely guarding the machine and a rope positioning system to prevent employee contact with the energized equipment (i.e., a leash for employees), would be effective methods to protect employees.  Finally, the letter opined that an administrative policy requiring employees to maintain a safe distance of six feet from partially-guarded and unguarded sweep augers was not an “otherwise equally effective means or method” that satisfies 1910.272(g)(1)(ii).

Shortly after OSHA issued the September 29, 2008 Interpretation Letter, the same insurance agent sent a second request to OSHA for further clarification, explaining that a sweep auger could not, by design, be completely guarded, and that the rope positioning system that OSHA suggested would be “extremely dangerous.”  This second letter specifically asked for OSHA’s interpretation as to whether an employee could be inside a grain bin with an energized sweep auger.  OSHA responded to this second request with another formal Interpretation Letter on Christmas Eve of 2009, with a direct “no.”  OSHA reasoned in the December 24, 2009 Interpretation Letter that if the methods proposed earlier by OSHA (i.e. guarding the operating side of the auger or putting a leash on employees) were ineffective, then the Agency was “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.”

Industry and Congressional Outreach to OSHA

The Christmas Eve 2009 Interpretation Letter caused considerable turmoil in the grain industry.  Employers wanted to comply with the Grain Standard, but found themselves scratching their heads about how to do that.  Many in the industry attributed the rejection of this long-standing practice for cleaning grain bins to OSHA’s misunderstanding regarding sweep auger operations.  Indeed, OSHA rebuffed several attempts by trade associations and industry leaders to help educate OSHA about safe methods of sweep auger operations, and repeated requests for additional guidance from OSHA for how grain handlers should resolve the dilemma surrounding the use of sweep augers with employees inside grain bins.

When OSHA did not engage with the industry further, trade associations and employers solicited the help of Congress for assistance in garnering additional guidance from OSHA as to what would be acceptable.  OSHA responded with two additional Interpretation Letters regarding sweep augers responding to requests from Senator Charles E. Grassley and Congresswoman Kristi Noem on May 16, 2011 and February 16, 2012 respectively.  Neither letter provided alternatives that would satisfy the “other equally effective means or methods” provision of 1910.272(g)(1)(ii), and simply reiterate that OSHA considered a sweep auger to be unguarded if the front operating side was not also covered.

Many industry representatives viewed OSHA’s interpretation letters as an indication that OSHA lacked complete understanding of sweep augers and how they are used in the industry.  For example, in the interpretation letter to Senator Grassley, OSHA describes sweep augers as “fast moving” with the potential to “sweep the worker into the discharge sump . . . resulting in a grain entrapment.”  Although the machines often have high RPM outputs, those RPMs drive the flighting that contacts and pulls grain, but it is wholly unrelated to the speed at which the augers move around bins.  The devices actually move very slowly around bins (sometimes multiple days to complete one cycle around a bin).


Meanwhile, while industry was trying to educate OSHA about its apparent sweep auger misunderstanding, and/or awaiting some clarification about how to operate sweep augers with employees inside a bin in compliance with the Grain Standard, OSHA began issuing citations to employers based on the new Interpretation Letters.  The Interpretation Letters, in conjunction with the surge of grain elevator inspections under the Grain Handling Facilities Local and Regional Emphasis Programs in all the major grain states in the U.S., raised the profile of this issue, and lead to a surge of citations for a practice that has been followed since sweep augers were invented.

Several of these citations were challenged by employers, including one to a federal OSHA sweep auger citation, and another to a Maryland OSHA (an OSHA-approved State Plan) citation, both of which were litigated to a decision by Administrative Law Judges.  In both cases, the sweep auger citations were vacated because the Judges reasoned that OSHA had not proven that any employees were in a “zone of danger” or that the augers were not adequately guarded.  Because the federal OSHA case was not appealed or taken up by the OSH Review Commission and the other case was in a State Plan state, neither decision provided a binding legal precedent on OSHA, nor did they shed light on what OSHA would consider to be “equally effective means or methods” for employees working inside grain bins with energized sweep augers.

Even though OSHA was losing the sweep auger cases in litigation, the Agency continued to issue citations for employees working inside grain bins with energized sweep augers, even if the employees were kept seven feet away from the moving parts of the sweep auger.  Employers were faced with the option of:

  1. Accepting a citation and facing the risk of Repeat citations (with penalties up to $70,000 per violation);
  2. Challenging the citations and incurring substantial legal fees; or
  3. Not emptying bins in an economical or efficient manner.

A Groundbreaking Settlement

Attorneys in Epstein Becker & Green’s national OSHA Practice Group represented a major grain handler in Illinois that received one of these sweep auger citations, and we found ourselves dealing with an OSHA Area Director and Regional Administrator who were uniquely knowledgeable about sweep augers from personal experience in agriculture, and who were willing to work with the employer in our case to develop a set of safety principles that would satisfy the “equally effective means or methods” language of the Grain Standard.

In our case, our client did allow employees to work inside grain bins with energized sweep augers, but they also employed a combination of administrative and engineering controls to ensure that no employee was ever within the zone of danger.  Accordingly, we contested the citation, and initiated a lengthy settlement discussion with the OSHA Area Director and the Solicitor’s office to address our citations and the overall landscape of sweep auger enforcement in the industry.

The Agency ultimately agreed to withdraw all of the citations issued to our client (and associated penalties), and the parties were able to agree to settlement terms that would provide guidance to the entire industry about sweep auger operations.  The end result was a settlement agreement that incorporated a set of “Ten Sweep Auger Safety Principles,” which if satisfied, OSHA would allow an employee to work inside a grain bin with an energized sweep auger.

The “Ten Sweep Auger Safety Principles” were sent to OSHA’s National Office in Washington, DC, where they were reviewed and approved for purposes of our settlement, and according to the Area Director and Regional Administrator, could be publicized for the industry’s benefit.

Ten Sweep Auger Safety Principles

Below is the list of Sweep Auger Safety Principles that OSHA, at the National Office level, has agreed to, and which should now serve at least as “guidance” to the industry for how to perform sweep auger operations in compliance with the Grain Standard:

  1. In accordance with 29 CFR 1910.272, no employee shall enter a grain bin until after completion of a bin entry permit, which confirms there are no engulfment and/or atmospheric hazards present inside the storage bin, or unless the employer or the employer’s representative who would otherwise authorize the permit remains present during the entire entry.  The grain bin hazard evaluation shall be completed by a qualified person.
  2. Before entering the bin to set up or dig out the sweep auger, the subfloor auger and the grain entry points must be de-energized and locked out.
  3. Before operating the sweep auger, the grate/guard on the sub-floor auger must be in place and secured.
  4. Employees operating the sweep auger cannot walk on the grain, if the depth of the grain presents engulfment hazard.
  5. It shall require that the sweep auger is provided with guards and covers per the manufacturers’ design, and the only unguarded portion of the sweep auger is the point of operation.
  6. A rescue trained and equipped observer, in accordance with 1910.272(g), must always be positioned outside the storage bin monitoring the activities of all workers inside the bin.
  7. If a worker is to enter the bin while the sweep auger is energized, the employer must utilize engineering controls within the grain bin to prevent workers from coming into contact with the energized sweep auger.  The use of only administrative controls without the use of an engineering control is not a sufficient means of worker protection.   Acceptable engineering controls may include:
    • Sweep auger equipped with an attached guard which prevents the workers contact with the unguarded portion of the auger in accordance with 1910 subpart O.
    • Sweep auger equipped with a control mechanism, such as a dead-man switch or other similar device, which will allow for the sweep auger’s operation only when the operator is in contact with device.   If this method is utilized as a means of worker protection, the worker must be positioned at least seven feet from the auger at all times it is energized; moreover, if worker(s) in addition to the operator of the sweep auger are in the bin, additional engineering controls (such as those described in section 7 of this criteria) must be used to protect those worker(s).
    • Portable guardrails are permissible, provided they are placed at least seven feet behind the sweep auger.  Note:  the use of a warning line, or other easily removable device, other than a portable guardrail, is not considered sufficient engineering controls.
  8. The auger must be provided with a positive speed control mechanism or bin stop device that prevents the uncontrolled rotation of the sweep auger.
  9. Workers are prohibited from using their hands, legs other similar means to manipulate the sweep auger while it is operating.
  10. If maintenance/adjustments are necessary to the sweep auger, the sweep must be unplugged, with the person making the adjustments maintaining the control of the plug, or locked-out in accordance with lock-out/tag-out procedures.

Practical Application of the Sweep Auger Safety Principles

As part of the settlement negotiations that resulted in the Ten Sweep Auger Safety Principles, the cited employer also developed and submitted for OSHA’s review and approval a specific Sweep Auger Policy that included actual, practical engineering and administrative controls the employer intended to use at its facilities.  Below is a non-exhaustive list of the engineering and administrative controls that OSHA affirmatively approved as being consistent with the Ten Sweep Auger Safety Principles:

  1. Safety Handle: A handle of at least seven feet in length attached to the back of the sweep auger that is equipped with a Dead Man Switch or Kill Switch.
  2. Attached Standard Railing: A Standard Railing mounted to the Sweep Auger with protective covering (such as snow fence) attached across the back of the Standard Railing.  The size of openings in the protective covering will conform to the allowable dimensions set forth in Table O in OSHA’s machine guarding standard.
  3. Portable Standard Railing: A portable, self-supported Standard Railing set in place behind the Sweep Auger, again with protective covering attached across the back of the Standard Railing.
  4. Operator Enclosure: A portable enclosure made of Standard Railing inside of which the Sweep Auger Operator can be stationed with a Dead Man Switch or Kill Switch while the Sweep Auger is Operating.  Alternatively, other electrical controls may be used as long as they shut off the sweep auger when the employee steps outside the enclosure.
  5. Operator Stand: A stand inside the grain bin mounted to the bin wall or elevated from the grain bin floor above the moving parts of the Sweep Auger, from where the Sweep Auger Operator can operate and/or observe the Sweep-Cleaning Operations.  The Sweep Auger Operator shall have access to a Dead Man Switch or Kill Switch.   Alternatively, other electrical controls may be used as long as they shut off the Sweep Auger when the employee dismounts the stand.
  6. Light Curtain: When it is demonstrated to be a feasible option, a light curtain may be installed with a triggering distance of seven feet around the sweep auger, which would shut off the sweep auger whenever an employee moves within the triggering distance.

Future of Sweep Auger Enforcement

Although this important settlement, the Ten Sweep Auger Safety Principles, and the engineering and administrative controls listed above were all approved at the highest levels within OSHA, OSHA has not archived its December 24, 2009 Interpretation Letter or the letters to Senator Grassley and Congresswoman Noem, nor have the Ten Sweep Auger Safety Principles been issued by OSHA as a new formal interpretation.  Accordingly, it remains to be seen what the Agency’s enforcement philosophy will be, and whether there is consistent application of these principles in all OSHA Regions.

Regardless, this settlement, and the corresponding Ten Sweep Auger Safety Principles and acceptable engineering and administrative controls, reflect a major step in the right direction in the partnership between the Ag Industry and OSHA.

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