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 can consult OSHA's website at https://www.osha.gov.

June 19 ,2014

Eric M. Dean
General Secretary
International Association of
Bridge, Structural, Ornamental and Reinforcing Iron Workers
Suite 400
1750 New York Ave. NW
Washington, DC 20006

Dear Mr. Dean:

Thank you for your March 12, 2013, letter to the Occupational Safety and Health Administration (OSHA). You ask OSHA to recognize the use of hazard access zones (HAZ) as an acceptable method to protect ironworkers who work in or near unfinished floor openings while performing steel erection work.

You describe a HAZ as a system that limits access to unfinished floors to ironworkers engaged in steel erection activities. The system requires the use of cones and extendable rails placed at least six (6) feet from unfinished floor openings that extend a minimum of twenty-eight (28) inches above a walking/working surface. A competent person must inspect the system each shift and the employer must provide special training for affected workers.

As described, this system does not comply with the requirements of Subpart R. For OSHA to allow the use of such a system, the Agency would require evidence that a HAZ, as described, eliminates or materially reduces the hazards as effectively as the Subpart R steel erection standards. At this time, OSHA does not believe that allowing the use of the HAZ you describe would be as protective of workers as the requirements of Subpart R.

However, on May 12, 2000, OSHA responded to a question regarding the use of a non-conforming guardrail system. In that letter OSHA announced that it would apply a de minimis policy for non-conforming guardrails where a warning line 15 or more feet from the edge or hole (in the case of a hole, measured from the nearest edge of the hole), when combined with effective work rules, would protect workers from unprotected sides or edges. Specifically, OSHA considers the use of certain physical barriers that fail to meet the criteria for a guardrail a de minimis violation of the guardrail criteria in §1926.760(d)(1) only when all of the following conditions are met:

  1. A warning line is used 15 feet or more from the edge (or nearest edge of a hole);
  2. The warning line meets or exceeds the requirements in §1926.502(f)(2);
  3. No work or work-related activity is to take place in the area between the warning line and the hole or edge; and
  4. The employer effectively implements a work rule prohibiting the employees from going past the warning line.

Thus, steel erection employers not protecting workers with a warning line system must fully comply with the fall protection and floor holes and openings provisions of Subpart R.

Thank you for your interest in occupational safety and health. We hope you find this information helpful. OSHA's requirements are set by statute, standards, and regulations. Our letters of interpretation do not create new or additional requirements but rather explain these requirements and how they apply to particular circumstances. This letter constitutes OSHA's interpretation of the requirements discussed. From time to time, letters are affected when the Agency updates a standard, a legal decision impacts a standard, or changes in technology affect the interpretation. To ensure that you are using the correct information and guidance, please consult OSHA's website at http://www.osha.gov. If you have further questions, please feel free to contact the Directorate of Construction at (202) 693-2020.


James G. Maddux, Director
Directorate of Construction