OSHA 1910 regulations include specific height requirements for fall protection. Fall protection is required for employees on walking-working surfaces with an unprotected side or edge that is 4 feet (1.2 m) or more above a lower level 1910.28(b)(1)(i). This can be achieved through guardrail systems, safety net systems, or personal fall protection systems 1910.28(b)(1)(i). For employees working near openings where the inside bottom edge of the opening is less than 39 inches (99 cm) above the walking-working surface and the outside bottom edge of the opening is 4 feet (1.2 m) or more above a lower level, fall protection is required 1910.28(b)(7). This can be achieved through guardrail systems, safety net systems, travel restraint systems, or personal fall arrest systems 1910.28(b)(7).

Here are some additional requirements:

• Guardrail Systems: The top edge height of top rails, or equivalent guardrail system members, must be 42 inches (107 cm), plus or minus 3 inches (8 cm), above the walking-working surface 1910.29 (b)(1).
• Personal Fall Arrest Systems: Personal fall arrest systems must be rigged so that an employee cannot free fall more than 6 feet (1.8 m) or contact a lower level 1910.140(d)(2)(ii). [4] [4] [4] [4] [1] [1] [1] [1] [1] [2] [3]