• Record Type:
    OSHA Instruction
  • Current Directive Number:
    STD 03-10-003
  • Old Directive Number:
    STD 3-10.3
  • Title:
    29 CFR 1926.451(a)(5) Scaffolding, General Requirements Guardrails
  • Information Date:
  • Standard Number:
Archive Notice - OSHA Archive

NOTICE: This is an OSHA Archive Document, and may no longer represent OSHA Policy. It is presented here as historical content, for research and review purposes only.

OSHA Instruction STD 3-10.3 October 30, 1978



SUBJECT: 29 CFR 1926.451 (a)(5) Scaffolding, General Requirements, Guardrails

1. Purpose

To establish guidelines on the use of chains, and wire, fiber, or synthetic ropes as guardrails on scaffolding.

2. Directives Affected


3. Background

a. Several inquiries, have been made regarding the meaning of the term "or the equivalent" when used in 29 CFR 1926.451(a)(5), which states:
Guardrails shall 2 x 4 inches, or the equivalent, approximately 42 inches high with a midrail, when required. Supports shall be at intervals not to exceed 8 feet. Toeboards shall be a minimum of 4 inches in height.
b. In addition, inquiries have been made regarding the use of chains and ropes for scaffold guardrails, in lieu of guardrails made of not less than 2 x 4 inches lumber. When chains or ropes are used for guardrails, questions are asked regarding the maximum allowable slack in the chain or rope and types of ropes that can be used.

4. Action

a. The use of chain and synthetic, fiber, or wire ropes as top rails and intermediate rails of guardrails used on scaffolding meets the equivalent requirements of 1926.451(a)(5) when in compliance with the following guidelines.

OSHA Instruction STD 3-10.3 October 30, 1978


(1) Rope or chain shall be secured to each support and taut at all times. It may be necessary to use a positive tensioning device to reduce the sag or catenary to a minimum.
(2) The rope or chain shall be free of sharp edges, burrs, or projections which may be a hazard.
(3) The maximum deflection of the top rail when a load of 200 pounds is applied in any direction at any point on the too rail shall not exceed 3 inches in one direction which includes the free hanging sag in the rope or chain.

5. Effective Date

This directive is effective upon receipt and will remain in effect until canceled or superseded.

Richard P. Wilson Director, Federal Compliance State Programs

DISTRIBUTION: A-1 E-1 B-2 HEW-1 C-1 NIOSH Regional Directors-1 D-4 & 5 NACOSH-1 Training Institute-4