Fall Arrest

KEEP ME HANGIN’ ON

Because you don’t want to have a falling out with your place of work

By David Dehaas

Eleven-thirty a.m. Two men, both in their twenties, are standing on a narrow window-cleaning platform on the outside of a large office building, twelve stories above the ground. They’re talking about the fact that they’d much rather be on the outside looking into the building than inside one of the tiny cubicles they can see through the windows. One man laughs and starts to say that he can think of other jobs he’d like even better, but he never finishes the sentence. That’s because one end of the platform suddenly gives way and swings down out from under them. From 120 feet above the ground, both men plunge toward the parking lot far below. But only for about four feet. That’s when their fall protection kicks in -- a system comprising a harness, lanyard, rope-grab and lifeline attached to a separate, secure anchorage point on the roof. It stops their fall and leaves them dangling, shaken but safe, to await rescue.

It's five-thirty and the crew in the warehouse is eager to go home after loading the last truck of the day. The truck driver climbs onto the bundled lumber on his trailer and starts pulling out the tarpaulin to cover his load. The tarp is heavy and it's stuck. Rather than walking forward to free it, the driver pulls as hard as he can. Several feet come loose and he backs up, spreading the tarp as he goes. It sticks again and he pulls, but the tarp won’t give. He leans back and gives another tug, and this time the tarp comes suddenly loose and he stumbles backward to the edge of the load and over the side. He falls exactly 11 feet, lands on his back on the concrete warehouse floor and is fatally injured.

These two incidents are typical of the fall protection situation in Canada today. The first involved work with a high and obvious risk of falling, in an industry in which fall protection is the accepted norm. The second involved work with a very real -- but not so obvious -- risk of falling, and it occurred in one of the many industries in which the need for fall protection is not well recognized and its use not well enforced. It seems that there are few industries between these two extremes -- and it also seems that the majority of workers (and the vast majority of accident victims) fall into the second category: workers who need fall protection but don’t have it.

In fact, there are about 100 lost-time fall-from-height accidents every working day in this country. That’s 26,000 every year, over 100 of them are fatal. Construction trades are unexpectedly in second place with 4,315 claims in 1996, just behind the 4,467 in manufacturing. Even more revealing is the fact that transportation and storage occupy third place with 4,014. Retail trades reported 2,092; and government services somehow managed to make it into fifth place with 1,869 lost-time falls from height.

So what is fall protection? Aside from "passive" protection, such as guardrails, fall protection consists of highly specialized personal protective equipment designed either to prevent falls in the first place or to bring a worker to a safe and controlled stop after falling.

First, let’s get the equipment straight. Harnesses, safety belts, lanyards, lifelines and anchorage points, the basic tools of the fall protection trade, are used for a number of distinct purposes. There are major differences in equipment, configuration and standards depending on the application they are used for, and most of the parts are not interchangeable.

* Fall arrest is designed to bring you to a relatively gentle stop after you fall from a height; think of it as low-impact bungee jumping. Fall arrest equipment consists of essentially three parts: a harness, a lanyard and an anchorage point.

* Fall restraint, or work positioning, is a system designed to keep you away from a fall hazard. It’s a sort of leash or tether that makes sure you can’t get close enough to the edge of the roof, for example, to stumble, fall or even be blown off the edge. It consists of a full-body harness or safety belt, and a lanyard to attach you to an anchorage point. In many cases, fall restraint is attached to a horizontal lifeline that allows lateral movement along an edge or elevated walk-way.

* Ladder climbing systems use a vertical lifeline (usually a cable) that runs the entire length of a fixed ladder. Workers climbing the ladder wear a full-body harness and attach themselves to the lifeline by means of a "rope grab" that slides up and down the line, but locks in the event of a fall.

* Controlled descent systems consist of a full-body harness attached to a lifeline. They allow workers to lower themselves safely and at a controlled rate. They are often used as backup to other systems, such as confined space entry, when fall protection is also required.

* Confined space entry systems are primarily designed to allow for retrieval of the wearer if he or she is incapacitated inside a confined space. They consist of a full-body harness attached at the shoulders to a lifeline. The lifeline, in turn, is attached to a winch, often mounted on a tripod, so that co-workers can reel in the worker if he or she runs into trouble.

While similar in some respects, these systems use different equipment, follow different standards and operate on different principles. They must never be confused, and the equipment must not be "mixed and matched".

FALL ARREST

Workers on communications towers, high-steel erection, window cleaning and construction typically use fall arrest systems -- or, at least, they should. By law, in every jurisdiction in Canada, anyone who faces a hazard of falling more than three metres (10 feet) is required to use fall arrest equipment that meets the legal standards.

Still, the three-metre threshold is an arbitrary one. A study of 1,954 fatal falls in the U.S. construction industry between 1985 and 1993 found that one in ten fatal falls was from a height of less than three metres. A further 22 per cent involved heights of just four to six metres. Together, these figures show the surprising fact that one third of all fatal falls are from less than 20 feet -- below the height of an average extension ladder, the peak of a one-story bungalow, or the height of a typical highway overpass. (Those three examples, ladders, roofs and bridges or overpasses, are also the "big three" in sources of fatal falls -- perhaps because the need for fall protection seems less obvious in these situations.)

What’s the formula? How do you know when a worker needs fall protection? The key words in the legislation (with minor variations from province to province), are "where a worker is exposed to the hazard of falling". If anyone has to work at a height above the ground or floor, and if you can’t eliminate the hazard through enclosure, guardrails, work platforms or fall restraint, you need fall arrest.

Fall arrest systems consist of a harness, a lanyard and an anchorage point. First there is a full-body harness that straps on over the shoulders and thighs and includes a "D" ring attachment point at the back or chest. The harness spreads the force of stopping evenly over the torso, and leaves the fallen worker hanging upright in a fairly safe and comfortable position to climb back or await rescue.

In the past, safety belts that were worn around the waist were used in fall arrest systems; however, this had the potential to cause injury when the stopping force (the sudden jerk when you hit the end of the lanyard) was applied to the waist. Some workers even slipped out of their safety belts after falling. Also, workers left dangling for any length of time from a waist belt experienced considerable discomfort and could suffer further injury as a result. Standards and regulations have recently been changed to ban waist belts from fall arrest systems, and only the full-body harness is now considered acceptable.

LANYARDS

The second component of a fall arrest system is a shock-absorbing lanyard that clips onto the D ring on the harness. The other end of the lanyard is then attached to the third part of the system, an anchorage point. Lanyards have to be relatively short. They need to stop the worker before the fall gains enough speed to make the sudden stop at the end of the lanyard too violent, and they need to prevent the worker from falling far enough to strike obstructions on the way down -- or even to hit the ground. (Recently, a worker in Australia died after falling 20 feet to the ground. Investigators found that he had clipped together several lanyards totaling 21 feet in length.)

The usual legal standard is that the system must stop you within 1.5m -- just under five feet. The shock absorber, and there are several different systems in use, ensures that you are not snapped to a sudden, bone-jarring stop. It spreads out the stopping distance slightly so that your fall is slowed down smoothly. A typical lanyard starts out about four feet long.

Most lanyards use a shock-absorbing system originally designed for mountain climbers. Essentially, manufacturers take a six-foot lanyard and fold it back and forth on itself to shorten the lanyard to about four feet. The folded sections are then sewn together using special stitching; when a fall occurs and a sudden load is applied to the lanyard, the stitches tear out at a controlled rate, absorb some of the energy of the fall, and spread the deceleration over two feet.

All shock absorbers should carry an inspection tag listing the date of last inspection. Any shock absorber involved in a fall must be taken out of service and discarded or destroyed to prevent it from being used again.

LIFELINES

Because the lanyard needs to be fairly short to be effective, the worker’s ability to move around is severely limited. There are several variations in the equipment that can be used to give the worker greater mobility while still providing reliable fall protection. First, there is the retractable lanyard. It works much like the retractor mechanism in seat belts used in cars. If you pull it out slowly, it will unwind from the spring-loaded reel smoothly; move back and the reel winds up the slack. But if you fall, and the strap is pulled out sharply, an automatic brake engages and locks the strap. These systems are usually up to 20 feet long, allowing a good working radius for the worker.

A second variation is used when workers have to move up and down, such as in ladder climbing systems or when workers need a back-up when working from a movable platform on the outside of a building. This systems adds a fourth component -- a lifeline that attaches to an anchorage point and runs the entire length of the ladder or working surface. The worker attaches his harness to a device called an automatic "rope grab" or ascender. This device slides up and down the lifeline smoothly when it is moved slowly, and allows the worker to go up or down without restriction. However, if the worker falls, a friction-sensitive cam in the rope grab engages and locks onto the lifeline, stopping the fall.

There are also manual rope grabs available. They stay locked onto the lifeline until the worker releases the lock to move the device up or down the lifeline. However, manual rope grabs, in which the lock is released by squeezing a button or lever, have led to several puzzling accidents in which workers fell all the way to the ground while holding the rope grab in the free position. Investigators later realized that workers who fell while moving the rope grab instinctively squeezed whatever they were holding, thus continuing to fall, when simply letting go of the rope grab would have saved them.

ANCHORAGE POINTS

The third major component of a fall arrest system is the anchorage point. This is where the lanyard or lifeline is attached to something strong enough not only to hold up the wearer, but also to withstand the tremendous load on the line when a falling, 300-pound worker hits the end of the lanyard.

The basic rule of anchorage points is that they must be absolutely positive and absolutely secure. If anyone has to wonder if the anchorage will hold, it’s not good enough. Equipment available for anchoring fall arrest systems includes the following:

* cross-arm straps for attaching lanyards to secure, fixed structures such as I-beams or structural members of a building;

* chain cross-arms that can be used to secure fall arrest systems to girders;

* eye-bolt systems that can be permanently attached to metal beams and girders;

* beam clamps;

* beam trolleys that can roll along I beams to give the worker mobility; and

* roof anchors that can be bolted to the joists or beams on a roof.

Improper anchorage points are the primary cause of failure of fall arrest systems, and there are very specific standards in the law regarding how strong they have to be. Essentially, an vertical anchorage point must be able to withstand a force of 22 kilonewtons (kN) – that’s about 5,000 foot-pounds. For horizontal lifelines used with fall arrest, the strength required is in the order of 71 kN. This sounds like a lot, but it isn’t. All fall arrest components have to be able to withstand twice the load to which they may be exposed (that’s the safety factor), and they have to be able to stop even the heaviest worker.

FALL RESTRAINT

Fall restraint is used to keep workers in a safe position -- away from the place from which they might otherwise fall. It consists of either a full-body harness or a waist belt attached to a lanyard, which, in turn, is attached to an anchorage point. (Fall restraint is the one application in which waist belts are still considered acceptable.)

Most oh&s legislation in Canada does not make specific reference to fall restraint. The legal wording in Ontario, for example, is, "where a worker is exposed to a hazard of falling" he or she must use "fall arresting equipment". Where does fall restraint fit into this picture? Simple. If a worker is secured by a proper fall restraint system, he or she is not "exposed to a hazard of falling".

A typical fall restraint lanyard is six feet long and does not include the shock absorber found on fall-arrest lanyards. Attachment to the belt or harness should be at waist level. Fall restraint is often attached to a horizontal lifeline so that the worker can move back and forth while still being prevented from approaching, for example, the roof edge. Workers in man-lift cages typically "tie off" with fall restraint. (Workers should not tie off to scaffolds unless they are permanently secured to a building or structure; there are regulations regarding the securing of scaffolds. An independent, separately attached fall-arrest system is a good backup for workers on scaffolds and platforms.)

Anchorage points for fall restraint typically require a capacity of four kilonewtons (about 900 foot-pounds), clearly much less than the 22 kN required for fall arrest. This is because the system is designed to prevent falls -- and therefore does not have to deal with the sudden stress of arresting a fall.

TWO QUESTIONS

The large majority of falls from height -- over 90 per cent of them -- happen to workers who did not have fall protection. Most of the rest had protection but were not using it, for whatever reason, at the time of the accident. Only a minuscule percentage happened to workers using fall protection that failed.

So the entire issue of fall protection in the workplace boils down to two fairly basic questions: Is any worker at risk of falling? And what are you going to do about it?

The first question requires assessment of the workplace for fall hazards -- and not just those jobs and tasks involving regular work procedures or even special projects. What about the electrician who services wiring near the ceiling? What about the maintenance people who replace light bulbs in the warehouse? The handyman who checks the drains on the roof? And another large area not to be overlooked: What about contractors who come on your site to repair the roof, clean the windows or install new equipment?

Systemic or administrative controls are by far the best solution. If fall hazards are rare, occasional and/or not directly related to the work normally performed, the hazardous task also tends to be ad hoc and not covered by clear procedures or training. Perhaps you can afford to remove the hazard altogether.

Get rid of that rarely used, 28-foot extension ladder that invites those extremely risky, spur-of-the-moment decisions to climb to a height to perform whatever odd job suddenly comes along. Use a pole attachment to change high light bulbs from floor level. Use a proper man-lift cage attached to a forklift truck (together with fall restraint and crew training) instead of a ladder for work at elevation indoors. Move the task -- reading a meter, opening a roof vent, adjusting a valve -- to floor level by moving the device or attaching control extensions. Remove the reason for working at heights. If workers go on the roof two or three times a year to remove snow or pools of water, get the roof fixed or properly sloped once and for all. Or contract out one-time jobs at elevation for which your people are neither equipped nor trained.

When tasks performed at height are frequently required, or if they are an intrinsic part of the job, engineering solutions are often the best and safest way to go. Install permanent, safe access points to elevated areas. Install walkways with guardrails. Enclose elevated work areas. Build safe work platforms.

Still, there are jobs, tasks and situations that do not lend themselves to systemic or engineering controls. For these, you will need a fall protection program. In other words, merely making fall protection equipment available isn't nearly enough.

You start with a policy; not a vague statement of high ideals, but a firm decision, an enforceable order from management that says, "Use fall protection". Then there’s the workplace assessment (and/or task analysis) that determines when, where, by whom and under what circumstances fall protection is required. This is followed by design of fall protection systems and acquisition of equipment. Then training of workers and supervisors. Followed by inspection, auditing and supervision. And continuous fine-tuning of the program.

Like the fall-arrest lanyard that is the only thing between a worker and the ground below, the fall protection program is the only thing that stands between your workplace and injuries or fatalities caused by falls from height. All the components have to fit and function together reliably. All the time.

It all came together for the two window cleaners left hanging at the start of this article. They were rescued by co-workers a short time after their platform failed. Neither was injured. All of which demonstrates that, when your life is on the line, fall protection can do the job -- as long as that line is connected to a secure anchorage point. 

David Dehaas is the editor of OHS CANADA.

TIE ONE ON

* In work environments where there is exposure to alkaline or neutral substances, choose nylon belts, harnesses and ropes. In environments where there is exposure to acidic substances, choose polyester materials. (It’s a good idea to check with the equipment supplier to determine compatibilities.)

* The attachment points for lanyards vary according to the purpose. Fall arrest lanyards are attached to a D rig at the back, between the shoulder blades; fall restraint lanyards are attached at hip level; lifeline lanyards or rope grabs are attached to a D ring at the chest. Confined space rescue cables are, ideally, attached to two rings at the shoulders since their purpose is to drag an unconscious worker back to the entrance and out.

* If you use a lifeline with rope grabs, make sure that the rope and all rope grabs in use are fully compatible, especially with regard to rope diameter. A too-large rope, which may still appear to fit in the rope grab, could wear excessively or cause the rope grab mechanism to fail. A too-small rope may slip through the device when exposed to the full load of a falling worker.

* When setting up fall arrest equipment, inspect the area for sharp edges, pinch points, and sources of heat that could wear, cut or burn through the lanyard if a worker should fall and be left dangling.

* A rescue plan is part of the fall protection picture. If a worker is left dangling from his or her fall arrest, do you have a rescue plan in place?

* Workers who require fall arrest must never work alone. What if they fall after everyone else has gone home and there is no one there to rescue them?

* Never climb above the attachment point of a fall arrest lanyard (since you could double the falling distance before the lanyard could stop you).

* Never use more than one lanyard clipped together. Coming to a sudden stop after a 10-foot fall -- as would be the case if you used two lanyards -- would apply a tremendous shock to your body, increase the risk of hitting something on the way down and over-stress the lanyard and anchorage.

* Never mix fall restraint components with fall arrest components. If a worker uses a restraint lanyard for fall arrest, for example, he’ll be missing the shock absorber -- which could injure him and/or over-stress the anchorage point.

* Don’t allow fall restraint anchorage points (which have a much lower strength requirement) to be confused with fall arrest anchorage points. Remove them altogether when the restraint work is done so that you don’t leave an inviting-looking trap for the next fall arrest user; or, if they must be permanent, attach a warning sign: something persuasive like, "Not Strong Enough For Fall Arrest".

* Always visually inspect a snap hook after attaching it to a harness or anchorage point. Merely hearing it click isn’t enough. (There have been fatal accidents in which it was later found that the connector had not been properly closed.)

* Always check your body harness for kinks and twists in the webbing after putting it on. The harness should fit snugly without being uncomfortably tight.

* Always set up the attachment point for fall arrest or fall restraint between the safe access point and the hazard; having to walk past the hazard to reach the attachment point defeats the purpose of the whole exercise.

* Do not modify fall protection equipment in any way. Do not tie knots in lanyards to shorten them, make splices in lanyards or lifelines or attempt repairs to hardware.

* Beware of using "mix and match" systems with different components made by different manufacturers. Not all are compatible. Check with your supplier to ensure compatibility.

* Old or infrequently used fall protection equipment may not comply with current standards and therefore not provide an acceptable level of protection. Standards change, so check the labels for current CSA or other acceptable standards. If you can’t find standards-certification labels, do not allow anyone to use the equipment.

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