Fall Restraint Systems

A fall restraint system uses a harness and a short connection to an anchor so you physically can’t reach the edge. Unlike fall arrest, nobody falls, so there’s no fall to stop, no fall clearance to calculate and no one hanging in a harness waiting for rescue. When it’s possible, restraint is usually the better choice.

Worker on a roof with a lanyard length that stops them short of the edge.
Fall restraint: the lanyard stops you short of the edge

Restraint vs. arrest

Fall restraintFall arrest
Can you fall?No. You can’t reach the edgeYes. The system stops the fall
Fall clearance neededNoneOften 18 feet or more
Shock absorber neededNoYes
Rescue planNot needed for a fallRequired
Injury risk if it’s usedVery lowArrest forces, swing, suspension trauma
Main limitationOnly works when the anchor is far enough from the edgeWorks right at the edge

Where restraint works well

Restraint works poorly on steep roofs, where you could slide even before reaching the edge, and anywhere you need to work at the edge itself.

Setting it up

  1. Find the nearest edge. Measure from the anchor to every edge, corner, skylight and roof opening you could walk toward. Corners are farther away than the sides, so the nearest straight edge usually controls.
  2. Pick the length. Your total reach is the lanyard length plus your harness and body. Set the lanyard so that when it’s fully tight in any direction, your feet stop well short of the edge. Many companies require a few feet of margin.
  3. Use the right connector. A fixed-length lanyard, an adjustable rope lanyard or a rope grab on a lifeline all work. Some SRLs can be used for restraint; check the instructions.
  4. Test it. Before starting work, walk toward the edge in every direction with the line taut to confirm you stop short.
  5. Recheck whenever you move the anchor, change lanyards or the work area changes.

Anchors and equipment

Warning: If the lanyard is long enough to let you reach the edge, it’s no longer a restraint system. It must then meet all fall arrest requirements, including a shock absorber, clearance and a rescue plan.

Common mistakes

Set-up checklist

Standards & references

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