Vertical Lifelines & Rope Grabs

A vertical lifeline is a rope or cable hung from an anchor above you. A rope grab rides on the line and connects to your harness. It slides as you move, and locks if you fall. It’s common on steep roofs, suspended scaffolds, swing stages and some climbs.

• Construction
• Roofers
• Window & facade work

The rules

• One worker per lifeline. When vertical lifelines are used, each worker must be attached to a separate line.
• Strength: vertical lifelines must have a minimum breaking strength of 5,000 pounds, and the anchorage must support 5,000 pounds per worker (or be designed by a qualified person).
• Independent anchor: on suspended scaffolds, your lifeline must be anchored separately from the scaffold’s support lines. If the scaffold falls, your line has to hold.
• Protect the line from cuts, abrasion and heat. Use edge protectors where it runs over a roof edge or parapet.

Rope grabs

• Match the grab to the line: rope grabs are made for a specific rope diameter and type (and some for cable). The wrong rope may let the grab slip.
• Install it right side up. Most have an arrow that must point up toward the anchor. Upside down, it won’t lock.
• Keep it above you. Position the grab at or above your D-ring to limit free fall. Trailing grabs follow you automatically; manual grabs must be moved by hand.
• Don’t hold it open or grab the device while you fall. Panic grabbing can stop it from locking. Many grabs have anti-panic features, but don’t rely on them.
• Use the right lanyard between grab and harness, usually short and with an energy absorber, as the maker specifies.

Setting up the line

• Anchor the line overhead, as directly above the work as possible, to prevent swing falls. See Swing Falls.
• Let the line hang to the ground or the next level, or tie a stopper knot or install an end stop at the bottom so the grab can’t slide off.
• Some systems use a weight at the bottom to keep the line taut so the grab follows smoothly.
• Allow for rope stretch in your fall clearance. Long lifelines stretch more.

Inspect before use

• Rope has no cuts, fuzzy or melted spots, stiffness, discoloration or chemical damage
• Cable has no broken wires, kinks or corrosion
• Rope grab locks when tested by a sharp downward pull, and moves freely otherwise
• Grab and lanyard are the right type for this line
• Anchor and connectors are sound, and the line is tied or terminated as the maker requires

On fixed ladders, ladder safety systems use a rail or cable with a sliding sleeve that works on the same idea. See Fixed Ladders and Suspended Scaffolds.

Last updated: October 2, 2026