Hanging on a Line
If any feature seems questionable, do not use the unit.
- By Marty Sharp
- Jul 01, 2006
WE sometimes hear the expression, "His life is hanging by a thread." This becomes true literally for those who fall while protected by a "fall arrest system." By definition, this "system" consists of an anchorage connector, a body harness, a lanyard, deceleration device, lifeline, or a suitable combination of these.
This article will discuss one such deceleration device, the "retractable lanyard." What is it? How should it be used properly and safely? What are its advantages? Are there disadvantages?
OSHA defines a "retractable" as a deceleration device containing a drum-wound line that can be slowly extracted from, or retracted onto, the drum under slight tension during normal employee movement, and which, after onset of a fall, automatically locks the drum and arrests the fall. The disc brake system, activated by any sudden movement, functions much like a seat belt. Once activated, it will stop the action of a fall.
ANSI Test Method, OSHA Requirements
One ANSI test for a retractable reads as follows:
4.2.7 Full Body Harness with Self-retracting Lanyard (FBH +SRL)
For integral (FBH +SRL) systems, the FBH constituent shall be separated from the SRL constituent and each shall be independently tested in accordance with the procedures in 4.3.3 and 4.3.7. In addition, the following test shall be performed. In accordance with the manufacturer's instructions, attach the SRL to the load cell that is connected to the test structure. Put the harness on the test torso, fasten all buckles, and adjust it snugly as though the torso were a person. Connect the line constituent of the SRL to the harness fall arrest attachment. Attach the quick release mechanism to the test torso (neck ring for "feet first" drop and crotch ring for "head first" drop). Hoist the test torso to a level at which 36 inches plus or minus 1 inch (917 mm - 25 mm) of SRL line is extended from the SRL orifice. Mark the SRL line at the orifice. The horizontal distance between the quick release mechanism and the orifice of the SRL shall not exceed 12 inches (305 mm). Do not lock the SRL and do not inhibit the retraction of the SRL line. Release the test torso by activating the quick release mechanism. After the drop, the torso is to remain suspended by the harness for a period of 5 minutes. During the post-fall suspension period, measure and record the angle at rest. Measure and record the parameters set forth in 3.1.2. The arrest distance is measured from the mark on the lifeline to the lifeline orifice on the SRL after the drop with the test weight at rest.
NOTE: The arrest distance must not exceed 54 inches (1,372 mm) to be in compliance with 3.1.2. Perform the test once each for a "feet first" and a "head first" drop. A new system test specimen may be used for each test.
OSHA states "self-retracting lifelines and lanyards which do not limit free fall distance in 2 feet or less . . . shall be capable of sustaining a minimum tensile load of 5,000 pounds applied to the device with the lifeline or lanyard in fully extended position." Also, "Self-retracting lifelines and lanyards which automatically limit free fall distance to 2 feet or less shall be capable of sustaining a minimum tensile load of 3,000 pounds applied to the device with the lifeline or lanyard in fully extended position."
Retractables may use either cable or new, high-strength synthetic ropes as the lifeline component. Working capacities range from 7 or 8 feet to 150 feet. Cable offers superior chemical and abrasion resistance and should be selected over webbing as required.
Certification and Inspection of Retractables
For years, manufacturers required that a retractable be certified annually. Standard recertification included automatic replacement of selected parts, while all other components were inspected and replaced as needed. The administration process for the user was cumbersome to the breaking point.
Most manufacturers have now abandoned the mandatory annual recertification in favor of increased end user training. Load indicators reveal when a device has been involved in a fall and must be returned for inspection, repair, and certification.
Along with the other components of your fall arrest system, your retractable must be inspected before each use. Become familiar with the warnings on the label. Inspect the housing for cracks or severe dents. Check for any missing or loose bolts, nuts, or screws. The connection bracket must not be cracked or distorted. Inspect the hook, latch, and swivel for distortion.
If a carabiner is a part of your system, make certain it has no distortions or cracks and that it operates properly.
Extend the cable or web line the full length and inspect for kinks, broken wires, abrasion, rust, fraying, nicks, broken or loose stitching, or burns. The thimble should not be distorted. Test the braking mechanism by giving the line a quick downward tug. If any feature seems questionable, do not use the unit.
A True Story
A few years ago, I had a customer who kept tripping the load indicators while claiming no falls. Retractables continued appearing at our plant for warranty work. I knew something was wrong because my problem was unique to this single job site. I decided to check it out for myself.
While meeting with the safety director, I noticed a tractor towing a forklift using one of our retractables as a tow strap. What a misuse of a product! The safety director and I jumped at an opportunity and scheduled a few early-morning training seminars. The problem was solved.
The lesson: Retractables make lousy tow straps.
Why Use a Retractable?
Retractable lanyards are used in a wide range of work situations where mobility is required. They may be conveniently anchored to any approved overhead anchorage. (They must not interfere with ladders or vertical work areas.) OSHA 1926.500, the fall protection standard for construction, simply says, "anchorage means a secure point of attachment" that must be able to sustain the weight and impact of a fall.
Fall-arrest anchorage points must be independent of any other anchorages, such as those used to support scaffolds or suspended platforms. When evaluating an anchorage, both the direction and magnitude of applied force should be considered. They must be capable of supporting at least 5,000 pounds per employee or, alternatively, be designed and installed under the supervision of a qualified person and used as a part of a system that has a safety factor of at least two. Beam anchors offered by most manufacturers meet these criteria.
Today, most retractables are designed to be mounted in any position, providing additional convenience for the worker. Use of a retractable also eliminates any tripping hazard. While all this freedom and convenience is a big advantage on the job, the worker must not become too carefree. Of concern is the "pendulum" or "swing" action of a fall.
For example: You are working 12 feet above the ground, wearing a full-body harness with an 11-foot retractable lanyard anchored 2 feet above your head. You walk the full 11 feet from the anchorage point. Then, reaching to complete a task, you lose your balance and fall. How well are you protected? The swing action allows you to drop 11 feet, plus the height of your body! You will hit the ground.
The lesson: Retractables afford mobility on the job, but always consider the "pendulum" action should you fall.
Another True Story
A call to my office recently was a complaint that our retractables could not be mounted on the floor of a bucket truck. I assumed he thought they would not work if turned upside down. Because they operate by centrifugal force, as stated earlier, they will operate correctly, sideways, right-side up, upside-down, or in any position in between. He was still concerned, so we agreed I would visit the job site to get more information.
Here is what I learned. The buckets, although raised to maximum height, were not high enough for the job. The workers, resourceful as they were, simply climbed out of the bucket and moved higher, sometimes high enough to max out the 11-foot retractables they wore. If they would have fallen, they would have experienced more than a 20-foot free fall. The lines on the retractables would have simply snapped when subjected to the force generated.
The safety director who called was right: Working conditions on this job site were anything but safe.
Self-retracting lifelines, retractables, are terrific safety devices. They solve problems and have saved many lives, but only when used properly.
Employees must be trained. That's our job. Don't leave their lives "hanging on a line."
This article appeared in the July 2006 issue of Occupational Health & Safety.
This article originally appeared in the July 2006 issue of Occupational Health & Safety.