HA-022 — FALL PROTECTION SYSTEMS FOR LADDERS — RIGID RAIL

HAZARD ALERT

Some fall arresters riding on vertical rigid rails employed in permanent fall protection systems for vertical ladders (FPS4Lad) may not arrest some accidental falls subsequently resulting in injury or death of their users.

BACKGROUND INFORMATION

Several injuries and fatalities involving climbers who used FPS4Lad installed on towers have been recently attributed to malfunctioning of the fall arresters (a.k.a. gliders, sliders etc.) riding on rigid rails. The accidents were reported both in North America ^[1] and Europe ^[2].

The accidents were caused by the failure of the spring loaded cam to lock on the rail as required ^[3], ^[4].

ADDITIONAL INFORMATION

The European agency ^[2] has also reported some non-arrested falls caused by the fall arrester sliding off the end of the rail. This type of accidents can easily be prevented by strengthening the stoppers at the end of the rail.

RECOMMENDATIONS FOR USERS OF FPS4LAD WITH RIGID RAILS

Short term. Until it is determined by additional, non-standard tests, that their FPS4Lad are safe, all climbers using these systems shall use a back-up fall arresting systems (FASs). Such FASs may include a Y-shaped, double-leg lanyards, the First-Climb FASs, or other safe systems.

Long Term. If the additional, non-standard drop tests were to result in non-arrests, the tower owners¿ investment in these systems can be preserved by exchanging only the fall arresters for the safe ones leaving the installed rails unchanged.

RECOMMENDATIONS FOR MANUFACTURERS

We recommend the re-testing of all FP4Lad systems which employ rigid rails using an articulated manikin during the special, non-standard drop tests that simulate a backward falls. If necessary, we recommend that the fall arresters are re-designed to employ, in addition to (or exclusively) the cam, an inertia type locking mechanism, or other safe mechanism.

RECOMMENDATION FOR STANDARD WRITING ORGANIZATIONS

The current technical standards for FPS4Lad require revising by the inclusion of the drop tests that would involve an articulated manikin falling backwards.

APPENDIX

The mechanical cam principle utilized in majority of FPS4Lad with rails is also employed in systems which use a wire rope instead of a rigid rail. According to our European sources ^[2], some of these fall arresters may not perform safely either. However, the issuer of this Alert is not aware of any specific accidents involving failure to stop the fall of any FPS4Lad with a wire rope.

Lanyards consisting of a core, either shock absorbing or just stretching (the so called non-trip lanyards) or both are becoming ever more popular due to their benefits of lowering the shock load, minimizing tripping and relatively low cost. Their characteristic feature, which distinguishes them from other lanyards are wrinkles in the outer web tube. In general the users’ knowledge of how these lanyards work is very poor. Most of the FAS users have better training in materials handling than in fall protection. Until other measures are developed, a proper training in fall protection with the emphasis on the before-use inspection of equipment seems to be the best way to minimize this hazard. When properly used by trained personnel these lanyards are very safe.

REFERENCES:

1. The Safety Notice at www.saf-t-climb.com
2. Health and Safety Executive (UK) ¿ Safety Warning re. HAC Fixed Rail Vertical FAS at www.hse.gov.uk
3. BSI (UK) PH5 Safety Warning ¿ Vertical Rigid Rail Fall Arrest Systems -published by HSE at www.hse.gov.uk
4. Testing of ladder climbing systems ¿ confidential report (USA) ¿ not available to general public.
5. NASA (USA) Safe-Alert. Document No. N4-S-07-01. Restricted circulation.

Prepared by: Andrew C. Sulowski, P.Eng.,

Sulowski Fall Protection Inc.; www.fallpro.com

Toronto, July 31, 2008