What is the required height for top rails in a guardrail system according to OSHA?

The required height for top rails in a guardrail system is specifically set at 42 inches, with an allowance of plus or minus 3 inches. This standard is crucial for ensuring worker safety on elevated surfaces, as guardrails are designed to prevent falls, which are among the leading causes of injuries in the construction industry.

Setting the height at 42 inches offers a balance; it is tall enough to provide a physical barrier while still allowing visibility over the guardrail for workers and supervisors. The tolerance of plus or minus 3 inches acknowledges that there might be variations due to different construction methods or materials, ensuring flexibility without compromising safety.

In practical terms, this means that guardrails must be installed such that their top edge falls within the range of 39 to 45 inches for them to be compliant with OSHA standards. This regulation helps create a safer work environment by reducing the risk of falls from heights.