What is the maximum diameter of a sphere that guards must prevent from passing if components requiring service are located within 10' of a roof edge?

The correct answer of 21 inches refers to the guidelines for fall protection and safety measures regarding maintenance access on rooftops. When components that require servicing are positioned within 10 feet of a roof edge, measures must be in place to prevent tools, materials, or any objects from falling off the edge, as they pose a significant risk to workers and individuals below.

In the context of fall protection, the measurement of 21 inches typically correlates with safety standards that dictate the maximum diameter of a sphere that can slip through a guardrail or safety barrier. This dimension ensures that the guardrails are designed to effectively prevent larger tools or equipment from falling, while also accommodating reasonable access for maintenance activities without compromising safety.

Other options, such as 13 inches, 33 inches, and 41 inches, do not align with commonly accepted safety standards. Selecting a dimension like 21 inches reflects a balance between usability for service personnel and maintaining safety regulations. Adhering to this measurement ensures that appropriate barriers are in place to mitigate the risks associated with working near roof edges.