Fall Protection Clearance
Required clearance below anchor = free-fall + decel + worker height + harness stretch + safety factor.
Example
You enter
- Connector type shock-absorbing-lanyard-6ft
- Worker height (ft) 5
- Harness stretch (ft) 1
- Safety factor (ft) 1
- Actual clearance below anchor (ft) 18
You get
- Required clearance 17
- Remaining clearance 1 ft
- Free fall (ft) 6
- Decel (ft) 4
- Connector label 6 ft shock-absorbing lanyard
- Status PASS (clearance margin)
Checked against published worked examples from: 29 CFR 1926.502 (fall-protection systems criteria) / ANSI Z359.
Details, formula, and sources
ScopePass/fail vs actual clearance to next lower level.
Formula or tableRequired clearance = free-fall + decel + worker_height + harness_stretch + safety_factor. Compared against the user-entered actual clearance below the anchor. Negative remaining clearance flags FAIL.
Source and editionOSHA 29 CFR 1926.502 (Fall protection systems criteria) by section. ANSI Z359 (Fall Protection and Fall Restraint) by name. Manufacturer connector-decel benchmarks from data/crosswalks/fall-protection-benchmarks.json.
Free access29 CFR 1926.502 free at ecfr.gov. ANSI Z359 licensed; manufacturer guides free at each manufacturer site.
What governsEstimate. Engineer of record governs the design and acceptance. Verify against the project structural drawings and the manufacturer's published capacity / chart.
API field namesconnector, worker_height_ft, harness_stretch_ft, safety_factor_ft, actual_clearance_ft, required_clearance_ft, remaining_clearance_ft, free_fall_ft, decel_ft, connector_label, flag
- Default free-fall 6 ft for personal fall arrest (PFAS)29 CFR 1926.502(d)(16)
- Default decel 4.0 ft for a 6 ft free-fall shock-absorbing lanyard (48 in maximum deployment; OSHA's 3.5 ft is the system limit, not the labeled stroke) / 3.5 ft for an overhead SRL (the 42 in arrest-distance cap)ANSI/ASSP Z359.13-2013; ANSI/ASSP Z359.14-2021 for the SRL
- Default worker height 5 ft from D-ring to feetengineering practice
- Default safety factor 1 ft marginengineering practice