Occupational Safety and Health Administration has standard spacing requirements for the post (vertical bar or support) of guardrails. Actually, you have to install it at a distance of 8 feet apart. Appendix B to Subpart M of Part 1926 - Guardrail Systems Non-Mandatory Guidelines for Complying with § 1926. This appendix serves as a non-mandatory. In general industries, when you work at a height of 4 feet or more you need guardrails that are needed by OSHA. But there is a flexibility of 3 inches. The effectiveness of these systems largely. (a) A standard guardrail shall consist of top rail, midrail or equivalent protection, and posts, and shall have a vertical height within the range of 42 inches to 45 inches from the upper surface of the top rail to the floor, platform, runway, or ramp level. Top rails must stand 42 inches (±3 inches), with midrails at 21 inches and toeboards at least 3.
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