First, I want to start off with the “scissor lift” dilemma and confusion. If you talk to two different people, you’ll get two differing opinions. Here are my thoughts on this:
I have watched while the battle has raged over whether the use of personal fall arrest harnesses by scissor lift operators is appropriate. The rationale on each side of the issue; pro and con, is intelligent, compelling, and complete with opinions from well informed, knowledgeable people.
The core argument from the pro-harness side stems from the assertion that scissor lift operators are more or less subject to the same falling hazards as anyone else working at height, so why not wear a harness?
On the con-harness side of things, some of the many the arguments follow the logic that if a scissor lift operator who is tethered to the unit goes over the guardrail, the resulting force(s) exerted on the machine when his/her weight jerks to a stop at the end of the lanyard’s travel could be enough to cause the unit to topple, sending it and the operator down. In addition, so I’m told, as the unit plummets down with the operator in tow, the lanyard serves to worsen things by “slingshotting” the operator into the ground and possibly under the machine, resulting in even greater injury than if he/she were able to free fall or jump clear.
If that’s not enough, neither OSHA regulations or ANSI/SIA standards require the use of personal fall protection harnesses for operators of scissor lifts. In fact, in many cases manufacturers do not provide an anchor point to connect the snap hook of a lanyard to and, OSHA prohibits tying off to a guard rail as per 29CFR 1926.502(d)(23)); “Personal fall arrest systems shall not be attached to guardrail systems.”
Some other issues that I have heard from the con side have to do with things like how wearing a harness restricts the movement of the operator or that wearing a harness may actually lull the operator into a false sense of security. I could go on, but I won’t.
I am going to go on record here and state that I believe scissor lift operators should be required to wear a personal fall restraint system (PFRS) consisting of a full body harness and non-shock absorbing lanyard provided there is an approved anchor point to connect it to. (In fact, if you dig into the OSHA regulations, you’ll find that “If the scissor lift manufacturer provides tie off anchor points at the base of the guardrail system, and the manufacturer’s user instructions require them to be used, then you need to be tied off with a PFRS”.)
Allow me approach each point of the “con” argument and, for what it’s worth, chip in my two cents.
First of all, take note of the suggestion for using a fall restraint harness rather than a fall arrest harness. Fall arrest systems are designed to stop a fall in progress while fall restraint systems prevent a fall from occurring… big difference. No fall means no excessive force on the unit, therefore no tip-over. The operator stays on the platform and the lift stays upright. Granted, a fall restraint harness may restrict the operator’s motion depending on the type of anchor point and how much mobility is actually required, but this is a fair trade in exchange for preventing a fall and possible fatality.
As for the “slingshot” effect, well, the laws of physics do not support that theory. A few centuries ago, Galileo discovered something we know today as, the law of falling bodies. Without going into great detail here, it basically states that everything that falls accelerates toward the earth at a rate of 32 feet per second/per second, until reaching peak terminal velocity (top speed), which is about 120 mph. So, if a scissor lift tips over, the operator and the platform are going to travel toward the ground at approximately the same speed; there will be no “slingshot” effect and certainly no need to jump from the platform. In addition, an operator wearing a PFRS will not sustain further injury because of multiple impacts with the ground from bouncing after the initial impact with the ground.
On the topic of jumping clear of the unit, there are serious concerns about the practicality of that notion. Even a conditioned athlete that is prepared and ready for the unit to tip would have difficulty picking the right moment to leap clear. When an aerial lift goes over it typically happens unexpectedly and quickly. The average operator is unlikely to have the physical prowess or presence of mind to do the right thing at the right time and even if he/she did, they would still have the actual fall to the ground with which to contend.
That brings us to OSHA regulations which, after all, are the law and the law says you don’t have to wear a harness to operate a scissor lift. I am going to avoid getting wrapped up in reg’s here the same way I do when I train operators, suffice to say that we are not attempting to determine if we have to wear it, but whether we should. Allow me to share a bit of wisdom that I usually impart to operators when they get a bit carried away with the law, which is; when you operate aerial lift devices, the only law you need to concern yourself with is the law of gravity. Respect for occupational safety and health laws will affect your relationship with OSHA while respect for gravity will affect your relationship with the ground!
As far as harnesses giving operators a false sense of security, it shouldn’t. It should give them a real sense of security. It is a simple fact that an operator wearing a PFRS is less likely to be killed by falling from the platform, which in itself is reassuring. It is also a fact that more scissor lift operators are killed by falling from the platform than by tipping the unit over and besides, if the unit goes over for any reason, the effect on the operator will be ugly with or without a PFRS.
The bottom line here is that every situation, or in this case, each use of the scissor lift has to be looked at from a different approach, so good judgment and the use of best practices are imperative.
9-23-2016 – Here is a link to a Scissor Lift Manufacturers letter, requiring the use of Fall Protection while using their product. https://goo.gl/hi2mvw