What is the minimum diameter usable for a safety line made of nylon or polyester?

What is the minimum diameter usable for a safety line made of nylon or polyester?

• A. 1/2"
• B. 3/8"
• C. 5/8"
• D. 3/4"

Answer: (C)

A safety line needs to be thick enough to carry the shock load of a fall, resist wear, and engage reliably with the hardware used for fall protection (rope grabs, carabiners, anchors). Nylon or polyester lines that are too thin can fail under dynamic loading or slip out of a gripping device, which would compromise the arrest system. A diameter of 5/8 inch provides sufficient cross‑sectional strength and stiffness to stay securely engaged, withstand abrasion, and work effectively with standard hardware and fittings. Smaller diameters, while sometimes approved in specific setups, may not meet the strength and compatibility requirements across common equipment, making 5/8 inch the safest, most reliable minimum in typical configurations.

A safety line needs to be thick enough to carry the shock load of a fall, resist wear, and engage reliably with the hardware used for fall protection (rope grabs, carabiners, anchors). Nylon or polyester lines that are too thin can fail under dynamic loading or slip out of a gripping device, which would compromise the arrest system. A diameter of 5/8 inch provides sufficient cross‑sectional strength and stiffness to stay securely engaged, withstand abrasion, and work effectively with standard hardware and fittings. Smaller diameters, while sometimes approved in specific setups, may not meet the strength and compatibility requirements across common equipment, making 5/8 inch the safest, most reliable minimum in typical configurations.