Best overall
Fall restraint
If the work can be done without reaching the edge, restraint removes the fall entirely — no clearance arithmetic, no rescue plan, no arresting force.
Warning
Fall arrest vs fall restraint
Both systems put a worker in a harness and both connect to an anchor, which is why they get confused. They are opposites: restraint keeps you from reaching the edge, arrest catches you after you have gone over it. The anchor ratings, the clearance requirement and the rescue obligation are all different.
Best free option
A guardrail
Neither system beats a rail you can build once and forget. Restraint and arrest are what you use where a rail cannot go.
Best for small crews
Restraint plus an SRL
A short restraint lanyard for the deck and one overhead self-retracting lifeline for the edge work covers most two- and three-person jobs.
Warning
The comparison, line by line
| Line | Fall restraint | Personal fall arrest |
|---|---|---|
| What it does | Stops you reaching the edge | Stops you after you go over |
| Anchorage strength | 1,000 lb per employee attached, or a 2:1 safety factor under a qualified person | 5,000 lb per employee, or a 2:1 factor under a qualified person — 1926.502(d)(15) |
| Fall clearance needed | None — there is no fall | Free fall up to 6 ft plus up to 3.5 ft deceleration plus body length plus margin |
| Maximum arresting force | Not applicable | 1,800 lb with a body harness — 1926.502(d)(16)(ii) |
| Rescue obligation | None | Prompt rescue required — 1926.502(d)(20) |
| Suspension trauma risk | None | Real, and the reason rescue has to be planned before the work |
| Works on a low deck | Yes | Often not — the clearance may not exist |
| Discipline required | High — the lanyard must stay short | Moderate — the system tolerates a longer leash |
Fall restraint
Restraint is a geometry problem. The anchor position and the lanyard length are chosen so the worker physically cannot reach the fall hazard. Nothing arrests, because nothing falls.
OSHA's construction standard does not define restraint separately — it is an accepted method because it means there is no exposure to a fall hazard at all. The practical consequence is that the anchorage does not have to meet the 5,000-pound arrest figure in 1926.502(d)(15); the widely used engineering figure is 1,000 pounds per attached employee, and OSHA has accepted that in letters of interpretation.
Caution
Restraint fails silently. A worker who clips a 6-foot lanyard where a 4-foot one was planned has converted a restraint system into a badly rigged arrest system without noticing. Fix the lanyard length at the anchor, not at the harness.
Personal fall arrest
Arrest accepts the fall and manages it. 1926.502(d)(16) sets the envelope: maximum arresting force 1,800 pounds with a body harness, free fall no more than 6 feet, no contact with any lower level, a complete stop, and deceleration distance no more than 3.5 feet.
Two obligations come with it that restraint does not carry. 1926.502(d)(20) requires the employer to provide for prompt rescue or ensure employees can rescue themselves — a suspended worker is on a clock. And 1926.502(d)(21) requires the system to be inspected prior to each use for wear, damage and other deterioration, which is what the harness inspection checklist formalises.
Body belts have not been part of an acceptable arrest system since January 1, 1998.
How to choose in the field
- Can a guardrail go there? Build it. Neither harness system is better than eliminating the exposure.
- Can the work be done without reaching the edge? Use restraint, and set the lanyard length at the anchor so it cannot be lengthened.
- Is there an overhead anchor and enough clearance below? Use arrest with a self-retracting lifeline; the SRL shortens free fall and therefore the clearance requirement.
- Is the clearance marginal? Stop. Re-anchor overhead or redesign the task — do not shorten the lanyard and hope.
The clearance arithmetic is worked through in at what height does OSHA require fall protection.