3D Model — Orbit & Inspect
Anatomy of a Self-Retracting Lifeline
Housing / Drum
Tough outer casing that encloses the spring-loaded retraction drum. Protects the internal braking mechanism from dust, moisture, and impact.
Retractable Cable / Webbing
The lifeline that extends and retracts as the worker moves. Available in galvanised wire cable or synthetic webbing depending on the model.
Snap Hook
The connection end that clips onto the worker’s harness dorsal D-ring. Must be self-closing and self-locking (double-action gate).
Swivel
Allows the cable to rotate freely without twisting or kinking. Reduces wear and prevents the lifeline from binding during use.
Braking Mechanism
Centrifugal brake that activates when the cable pays out too fast (a fall). Locks the drum within 600 mm of travel — similar to a seatbelt.
Shock Absorber
Integrated or external energy absorber that reduces peak arrest force on the worker’s body to below 6 kN. May be one-time use.
Anchor Connection
Top D-ring or carabiner for attaching the SRL to an overhead anchor point. Must connect to a rated anchor (≥15 kN for one person).
How It Works
An SRL operates like a car seatbelt. A spring-loaded drum continuously retracts the cable or webbing, keeping it taut as the worker moves.
During normal movement, the cable pays out and retracts freely. If the worker falls, the sudden acceleration triggers a centrifugal braking mechanism that locks the drum — arresting the fall within 600 mm.
This short lock distance is the key advantage over standard lanyards: less free fall = less fall force = less clearance needed.
Why SRLs Are Preferred
Lanyard free fall: up to 2 m + 1.75 m absorber
SRL lock distance: only 600 mm
Types of SRL
| Type | Medium | Best For |
|---|---|---|
| Cable SRL | Galvanised wire rope | Long range, heavy duty, construction |
| Webbing SRL | Synthetic webbing strap | Lighter weight, shorter range, confined areas |
| Leading Edge SRL | Reinforced cable | Sharp edges (concrete slabs, steel decking) |
Leading edge SRLs have cable reinforced against abrasion from sharp edges. Standard SRLs can be cut if the cable contacts a sharp edge during a fall.
Critical Rules
- Anchor ABOVE the worker — SRLs must be mounted overhead. Side or floor anchoring creates a swing-fall hazard and increases free fall distance.
- Never use horizontally unless the SRL is specifically rated for horizontal use (check manufacturer’s label).
- Check retraction before each use — pull out the full length of cable and let it retract. It must retract smoothly with no catching or sticking.
- Never tie knots in the cable — knots weaken wire rope by up to 50% and prevent proper retraction.
- One person per SRL — never connect two workers to the same unit.
- Keep cable taut — slack in the line defeats the purpose of the retraction mechanism and increases free fall distance.
Fall Clearance Calculation
SRLs need significantly less clearance than standard lanyards because the braking mechanism locks quickly.
Minimum Fall Clearance (SRL)
1.0m lock distance • 1.5m worker height below D-ring • 1.0m safety margin
| Component | Distance |
|---|---|
| SRL lock distance | 1.0 m |
| Worker height (below D-ring) | 1.5 m |
| Safety margin | 1.0 m |
| TOTAL minimum clearance | ≈ 3.5 m |
Compare: a standard lanyard with energy absorber needs 6.25 m minimum clearance. SRLs allow work at lower heights.
Inspection & Rejection Criteria
Inspect SRLs before every use. Remove from service if ANY of the following are found:
Reject Immediately If
- Cable doesn’t retract smoothly — catching, sticking, or failing to fully retract
- Housing cracked or dented — internal mechanism may be compromised
- Hook latch broken — gate doesn’t close or lock automatically
- Webbing frayed or cut — any visible damage to webbing-type lifelines
- Shock absorber deployed — energy absorbers are ONE-TIME USE only
- Corrosion — rust or pitting on cable, housing, or connectors
- Missing/illegible label — no identification = no use
- Any previous fall — must be returned to manufacturer for inspection
Good Condition Indicators
- Cable/webbing retracts and extends smoothly through full range
- Housing intact, no cracks, dents, or deformation
- Snap hook gate closes and locks automatically
- Swivel rotates freely
- Labels legible with current inspection date
- No signs of corrosion or chemical exposure
Applicable Standards
- AS/NZS 1891.3 — Industrial fall-arrest systems and devices — Retractable type fall-arrest devices
- AS/NZS 1891.4 — Industrial fall-arrest systems and devices — Selection, use and maintenance
- AS/NZS 1891.1 — Industrial fall-arrest systems and devices — Harnesses and ancillary equipment
- WHS Regulation 2017 — Chapter 6, Part 4 — Falls (managing risk of falls at workplaces)
SRLs must be inspected by a competent person at least every 6 months or per manufacturer’s instructions (whichever is more frequent). Records must be kept.