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.



April 17, 2006



MEMORANDUM FOR: Kenneth Gereke
Regional Administrator, Region III
ATTN: John McFee
Construction Coordinator, Region III
FROM: Russell B. Swanson
Director, Directorate of Construction
SUBJECT: Guardrail height requirements for construction activities in General Industry Facilities


This is in response to your e-mail submitted April 7, 2005. You ask for compliance guidance with regard to the application of Subpart M, Fall Protection, requirements for construction activities in a General Industry facility. We apologize for the long delay in providing this response.

We have paraphrased your question as follows:

Question: Scenario: Employees are engaged in construction activities on a walking/working surface at a General Industry worksite. The guardrails on that site have a top rail that is 36 inches from the walking/working surface. Under OSHA Directive STD 01-01-010 and subsequent proposed rulemaking, the use of such a guardrail by General Industry employees is only a technical violation of the General Industry standard 29 CFR 1910.23(e)(1), which otherwise requires a nominal vertical height of 42 inches.

Would the construction employer be in violation of §1926.502(b)(1) (Subpart M) of the construction standards, which requires the use of guardrails with a top rail that is 39 to 45 inches above the walking/working surface level?

Answer: Yes, it would be a violation of Subpart M if construction work were performed on an elevated walking/working surface that is guarded by a permanent guardrail system with a 36-inch top rail, even though that top rail height is permitted for General Industry work under STD 01-01-010.

Section 1910.23(e)(1) (Subpart D — Walking-Working Surfaces) of the General Industry standards states:


Railing, toe boards, and cover specifications. (1) A standard railing shall consist of top rail, intermediate rail, and posts, and shall have a vertical height of 42 inches nominal from upper surface of top rail to floor, platform, runway, or ramp level. * * * [Emphasis added.]

However, OSHA Directive STD-01-01-010 — Height of Guardrails in General Industry Applications notes:

* * *
C. Action. OSHA Regional Administrators/Area Directors shall classify technical violations of 29 CFR 1910.23(e)(1) as de minimis violations, where the employer has provided guardrails which meet the following specifications:
(1) Existing guardrailing shall consist of a top rail, intermediate rail, and posts, or equivalent, and shall have a minimum vertical height of 36 inches to 44 inches from the upper surface of the top rail to the floor, platform, runway or ramp level. [Emphasis added.]
* * *
E. Background. A Field Information Memorandum * * * was previously issued regarding the height of guardrails. * * * The intended revision [of Subpart D of 29 CFR 1910] is not yet available; therefore, to provide equitable enforcement which does not place unnecessary cost burdens upon employers, or have a direct or immediate effect upon the safety or health of employees, this instruction reissues the previous policy * * *.1

In addition, under General Industry's proposed rule on Walking and Working Surfaces (55 Federal Register 13360), guardrail systems with top rails that are 36 inches in height would similarly be "grandfathered."2 In support of that provision, OSHA noted in the preamble:

* * * that continuing to tolerate the use of guardrails as low as 36 inches (91 cm) would not unacceptably reduce employee protection and that the hazard to which to which employees would be exposed in replacing those guardrails would be greater than that from allowing the existing guardrails to remain in place. (55 Federal Register 13374) [Emphasis added.]

The applicable construction provision, §1926.502(b)(1) (Subpart M-Fall Protection), provides in part:

Guardrail systems. Guardrail systems and their use shall comply with the following provisions.
(1) Top edge height of top rails, or equivalent guardrail system members, shall be 42 inches (1.1 m) plus or minus 3 inches (8 cm) above the walking/working level. * * * [Emphasis added.]



The General Industry directive permits the use of existing, permanently-installed guardrails that have a 36-inch top rail. The rationale for that policy, as reflected in the preamble for General Industry's proposed rule on Walking and Working Surfaces, is that employee safety is not compromised by the use of such existing permanent guardrails and employee exposure to fall hazards would be increased by requiring the replacement of these guardrails.

In contrast, construction activities often include carrying tools and materials that are heavy, awkward to handle, and, in the case of large materials, can sometimes block the employees' view. In addition, unlike the general industry employer, a construction employer is not faced with the choice of leaving the permanent guardrails in place or replacing them. Instead, because construction work is by its nature temporary, construction employers typically install temporary guardrails. These guardrail systems are designed for temporary use under varied worksite conditions.

For example, some of these systems would allow a construction employer to erect a temporary guardrail system adjacent to the permanent guardrail system or to attach a temporary top rail to the permanent guardrail system to meet the applicable requirements in Subpart M. In addition, unlike the permanent guardrail systems in and on structures addressed in STD 01-01-010, these temporary guardrail systems are designed to facilitate repeated installation and removal. Consequently, the concerns regarding unjustified additional hazard exposure involved in replacing permanent guardrails is not applicable to the construction employees in your scenario.

In sum, when a construction employer protects its employees from falls with a guardrail system, that guardrail system must meet the requirements in §1926.502(b), including the top rail height requirement in §1926.501(b)(1), even where there is a permanent guardrail with a 36-inch top rail that, pursuant to STD 01-01-010, is acceptable for General Industry work.

If you need additional assistance, please contact us by fax or e-mail



1 It is our understanding that STD-01-01-010 was adopted in light of pre-OSHA General Industry practices. Specifically, in the Preamble of a proposed rulemaking for General Industry's Walking and Working Surfaces standard (Volume 55 of the Federal Register, page 13373 (Apr. 10, 1999)), OSHA offered the following explanation:

OSHA issued the directive because it recognized that employers with guardrails as low as 36 inches (91 cm) might have installed their systems in compliance with pre-OSHA building codes. The Agency was also concerned that employers would be unreasonably burdened by the cost of replacing their guardrail systems with new guardrail systems that were a nominal 42 inches (1.1 m) high. [Emphasis added.] [ back to text ]



2 It should be noted that OSHA considers a top rail, which is not in compliance with the existing standard but is in compliance with the proposed standard, a de minimis violation (see e.g., Byron R. Chadwick memo dated 3/8/1995; CPL 2.103 (Field Inspection Reference Manual)). [ back to text ]