safety

Scissor Lift Fall Protection - Required or Not?

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The need to have workers in body harnesses and personal fall protection (PFP) while operating a scissor lift has been and continues to be a point of healthy discussion and confusion for many. Well intentioned and knowledgeable safety professionals can and do disagree on this topic and if those who are expert cannot come to a consensus we certainly cannot expect those in charge of operating the equipment or supervising and managing the work to fully understand the hazards and provide the best controls for the situation.

There are several discussion points in this debate.  On one side there are those that see a well maintained and complete guardrail system as fall protection and where falls are seen as largely an employee behavioral, management and training issue.  They believe that if workers keep their feet securely on the platform, gates closed, etc. there is no fall hazard.   Followers of this line of thinking point to the similarities in someone working on a work platform or mobile scaffold with a guardrail system and no similar requirement for personal fall restraint systems (PFRS) or personal fall arrest systems (PFAS).   They may also point out that OSHA and ANSI/SIA in a plain reading of the regulation or standard do not require PFP.   They may further point out that wearing fall protection increases the hazards associated with crush injuries via getting caught in the controls or increases the hazards associated with the fall – perhaps in toppling the lift, pendulum effects and discussions about slingshotting the worker into the ground if a lift topples, no ability to jump free etc. to give some examples.  Others discuss complexity/confusion for workers in using the right personal fall protection system (PFPS) and discussions about arrest versus restraint, length of lanyards, type of lanyards, ability to actually move in the basket and perform the work, location and type of anchor points etc.   Other arguments relate to complacency in having a harness and a false sense of security.   

On the other side of the discussion are those that see OSHA and ANSI/SIA as minimum requirements, outdated and not the most protective, with some pointing out the requirements of the General Duty Clause and enforcement action related.  Followers argue that in general more is better and issues involving falls and scissor lifts are best controlled through personal protective equipment (PPE) and tighter controls to not allow a worker to climb up out of the platform.  They similarly point to manufacturer guidelines and white pages, interpretations from OSHA, EM-385-1-1 and similar as support of their arguments that PFP is required.  Some believe that anyone operating over 6’ needs to be protected and that the only law we need be concerned with is the law of gravity. Isaac Newton would be proud.  Followers disagree as to the best means and methods for a fall protection system and whether a fixed lanyard and restraint system or a self-retracting lifeline and arrest system is best but regardless of the precise connection device or anchor, the controls outweigh any increased risk associated with the fall protection system itself.  Further, many argue against concerns associated toppling the lift, sling shot effects, crush injuries and jumping free and in general feel they are overstated, largely unsupported or extremely rare and thus insignificant. 

Having crudely defined the main talking points and issues, it is worthwhile examining some of these viewpoints.

The next Darwin Award winner is….

The next Darwin Award winner is….

Falls and Scissor Lifts

Historically falls involving scissor lifts are associated with three prime factors:  climbing outside the basket, climbing up off the platform to gain elevation and leaning outside the rails.   Workers are generally not falling through the rails or in the gap created by a gate chain that was not secured.  There have been some instances where workers fall through the gate, however these often involve circumstances where employees knowingly pin open the entire gate so there is a gap in the complete guardrail system.  It should also be noted, that new ANSI/SIA standards for design of lifts are doing away with the chain gate and going with a rigid, self-closing gate with toeboard system which should reduce issues with hanging chains etc. though still does not address a worker who knowingly wires the gate in the open position.  It will take a while for older lifts to cycle out and/or get refurbished but as it relates to unsecured chains and falls this is mostly inconsequential.   

One also needs to differentiate between falls and tipping/overturn of the lift. In both, a worker falls, but they are distinctly different in a variety of ways that are obvious.  It should also be noted that some of the fatality reports are improperly classified as falls when in reality they are lifts being tipped, thus overstating the frequency of falls as it relates to scissor lifts.

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Falls Causing the Lift to Tip

Theoretically, it is conceivable that arrested falls could cause the lift to tip over, however data and research on the matter does not support such a theory at this point particularly since most falls from a lift (>80%) involve no PFPS and of the 20% where PFPS was involved, there is limited data indicating a concern with a fall resulting in a lift topping.  There have been a few studies which have involved a drop test and anchorage to the designated anchor points and the rails.   It is hard to draw a conclusion from these studies as the conditions involved (e.g. drop over nose of lift versus the side, on a shorter sized lift, straight drop in an upright mannequin, lift not on an incline etc.) do not fully replicate field conditions and the dynamics involved in a typical fall.  The new CSA and ISO standards require all anchor points for fall arrest to withstand a 300 lb drop test with load placed outside the rails and in a direction to create the most adverse stability condition.  The proposed ANSI/SIA standards have similar language.  Moving forward all new lifts with anchor points for fall arrest will be designed to withstand these impacts and the concern about falling and tipping should no longer be a concern.  One caution here however is that this requirement does nothing to address lifts currently out in the market.  Another important qualification of this standard should also be noted, namely the standard doesn’t require lifts to have anchor points for PFAS but rather sets standards for lifts that do.   If anchor points are only designed for PFRS (not PFAS), as most currently are in the U.S. then these standards do not apply, manufacturers would not be required to undergo this testing and people can continue to be put at risk if using the wrong PFPS.   Presumably manufacturers would provide lifts with the greatest functionality and perform the testing, but is not necessarily required.  All in all, most good evidence points to the notion that lifts tipping over when workers fall out of them is more a theory at this point than a significant concern.  In the future this should be even less of a concern as manufacturers continue to improve on the safety of their equipment.  This all said, regardless of whether a lift has been designed to not tip over in the event of a fall, I am sure someone, somewhere out there will set up a fall protection system with a long lanyard, have it fully elevated, on an incline etc. and prove me wrong.

Sling Shot Effect

The Sling Shot Effect is generally the theory that if a worker is tethered to the lift and the lift topples, that the worker will somehow be slung into the ground, into other surfaces, under the lift etc. via the momentum of the lift falling.  Looking at this with an eye towards the actual physics of the matter versus those observed by Wile E. Coyote one observes several points.   First, two objects of varying mass/weight free falling from the same point in space will hit the ground at the same time.   This of course is not however the reality of a lift being toppled and a worker outside the rails who free falls.  Namely the lift is not in a free fall but in contact with the ground and tipping over through an arc whereas the worker is likely in a free fall if outside the basket.   If the worker is in or on the basket when the lift topples, the worker goes down with the lift at the same rate of speed as the lift does.  If the worker somehow engages a parachute or their flying squirrel suit and the fall is through a great enough distance then perhaps those dynamics change slightly but in the split seconds it takes to fall we can safely assume the worker will impact the ground before, if free falling, or at approximately the same time and there is next to no slingshot action.  Workers who are tethered to the lift and grab on to something overhead as the lift begins to topple could generate some tension on their connecting device and get pulled off of whatever they are grabbing.  In this case, there is the potential for some sling shot effect in theory, but the connecting device and the holding force of the worker likely are not sufficient enough to elastically deform the lanyard so as to appreciably sling shot the worker out in front of the lift.  The only really significant effect approximating the sling shot effect is the angular momentum of the lift as it falls through an arc which would tend to throw the worker in the direction of the fall.   This would essentially be the same whether tethered off or not. 

Jumping Clear

Unless the worker is a parkour master with some precognition or has been bitten by a radioactive super spider, the idea that a worker can prepare and ready themselves to jump clear while the lift falls is extremely unlikely.  The timing is near impossible and when a lift topples, it is usually unexpected and happens very quickly.  This said, there are several instances where users have been able to anticipate the lift tipping and were able to jump and hold on to some overhead object as the lift begins to topple in hopes of being rescued later.  

Though the sample size is small, there is some indication that being tethered to the lift when the lift topples holds an increased risk of injury versus not but more research would need to be done to draw any firm conclusions.   It is also worth noting that most research would indicate that the odds of surviving a fall are better for a worker who rides a lift down and stays inside the basket versus is outside the basket.

Improved positioning of the lift would remove the need to get out of the basket

Improved positioning of the lift would remove the need to get out of the basket

OSHA Requirements

Scissor lift regulations can be found in the relevant section of the scaffold safety orders.   If the guardrail system is fully intact (e.g. up, locked in place, gate closed, proper height etc.), the operator keeps both feet firmly on the platform, no part of their body extends outward beyond the wheels etc., no fall protection is required.   Letters of Interpretation (LOI) and compliance directives provide some additional guidance but are not the law.   What LOI’s and enforcement guides often do however is refer to the non-mandatory Appendix C which references the ANSI/SIA A92.6-1990 standards.  The 1990 version of the standards states that the guardrails shall be installed and access gates or openings are closed per manufacturer's instructions. It then goes on to state that personnel “shall main­tain a firm footing on the platform floor while work­ing.” Otherwise, the ANSI A92-1990 standards are fairly silent when it comes to fall protection and it is not clear how a non-mandatory section of the OSHA regulations which reference an ANSI standard which does not have any language requiring fall protection can be guiding.

More current revisions of the ANSI/SIA standards state:

“The guardrail system of the aerial platform provides fall protection. If occupant(s) of the platform are required to wear personal fall protection equipment (PFPE), occupants shall comply with instructions provided by the aerial platform manufacturer (remanufacturer) regarding anchorage(s).”

It should be noted that the revised ANSI/SIA language has a different meaning than previous versions, namely it has the qualification of “if occupants…are required to wear”.   There are only a few instances where occupants would be required to wear fall protection and those include the removal of the guardrail system, an incomplete guardrail system, mandates by company policy, local requirements etc. Most manufacturers now supply anchorage points but of the top five scissor lift manufacturers in the U.S. only two consistently recommend (not require) users wear a full body harness with a lanyard attached to the authorized anchorage point. One of those manufacturers states that one needs to comply with “applicable government regulations” whereas the other requires that the system be a PFRS.   

Some people use an early version of the 2008 U.S. Army Corps of Engineers (USACE) EM385-1-1 rules as support for fall protection while using a scissor lift because of language such as this:

“Scissors lifts shall be equipped with standard guardrails. In addition to the guardrail provided, if the scissor lift is equipped with a manufactured anchorage, a restraint system shall be used in addition to guardrails.”

The Nov 2014 revision of the USACE EM385-1-1 rules more clearly calls out for a PFRS and in addition to guardrails, that PFRS shall be used provided the lanyard has built-in shock absorbers and is sufficiently short to prohibit workers from climbing out or being ejected from the platform. The rules further prohibit the use of a self-retracting device (SRD) unless permitted by the SRD manufacturer and used in accordance with manufacturer’s instructions. Clearly the USACE offer an opinion about what means of fall protection are required at USACE projects as it relates to scissor lifts. That said, it is important to note that though USACE rules reference OSHA they are not OSHA regulations and only apply to USACE projects.

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As to concerns about OSHA citations of the general duty clause for failure to follow the ANSI/SIA rules, without knowing any specific case where these rules were applied, I would caution that enforcement action supports both positions – for and against wearing fall protection.   Each case, compliance officer, interpretation of the rules etc. is unique and many of us can point to citations which were not justified for a variety of reasons, those that when appealed were vacated etc.   If a worker falls and gets hurt because they were climbing outside the guardrail system with or without PFP, several different rules could be cited including the general duty clause. That said, fear of citations as a reason for doing anything is problematic and certainly less effective than doing it based on sound methodology and value decisions. 

Crush Injuries

Opponents of wearing fall protection while working in the basket sometimes argue that the use of a harness and lanyard can increase the risk of crush injuries if the fall protection equipment gets tangled up in the controls. To be certain there have been instances where such incidents have occurred though they are rare.  It also should be noted that many lifts provide controls against such issues, including secondary triggers like foot pedals, emergency stop buttons which should be engaged once the platform has reached the working height and shuts off power to the control panel, toggle switches which turn off drive and lift functions etc. Further still, most control panels are moveable and thus if work needs to be done in the precise location of the control box, perhaps it is prudent to reposition the lift or relocate the controls.  Last, most of the incidents involving workers getting caught up in the controls have the workers climbing up out of the basket, which for the proponents of PFP is behavior the PFRS, if set up properly, is supposed to prevent in the first place.

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Restraint versus Arrest

There is much debate about the appropriate PFPS that should be implemented.   Breaking it down to basics, most of this discussion centers around issues of practicality.   Listening to the manufacturers, they require PFP, if used, to be a restraint system only.   However, for anyone who has ever done this type of work, a fixed length lanyard of sufficient length to prevent someone from being able to climb up and out of the basket also effectively impacts the ability of the worker to do the work and move around the platform.  To get around these issues, safety professionals often recommend longer lanyards or self-retracting lifelines (SRL’s).   Depending on the set-up, size of the platform and practices used, these systems generally do not work as a restraint system but rather an arrest system, again something the manufacturer prohibits.   Further, though the SRL solves the problem of being able to move and do the work, even with the shortest SRL’s on the market, a worker could easily leave the platform and fall, thus subjecting themselves to the hazards of the fall, striking objects below, potential tipping of the lift etc. particularly given the anchor point is usually below the level of their feet.    

Conflicting Guidance

Some manufacturers and safety professionals demonstrate compliance with fall protection by recommending the use of a 6’ lanyard to the mid rail or designated anchor points of the lift.   There are several challenges with this advice.   Not only would such a system most likely be part of a fall arrest system versus a restraint system, which most manufacturers prohibit, but OSHA guidelines prohibit attaching PFAS to guardrail systems.   If the manufacturers and safety professionals guiding our workers cannot even be consistent our worker’s have little hope.    

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False Sense of Security

Some argue that the use of a PFPS creates a false sense of security.   This could very well be a factor if the wrong decisions are being made.   PFPS’s should be effective and truly provide security.  If they don’t then we are doing something wrong.   As the saying goes, “The operation was a success, but the patient died.”   Mandating that all workers use a harness attached with an SRL that allows workers to leave the basket and not addressing the issues of why workers are leaving the confines of the basket is just such a practice which can create a false sense of security.   Is it better than wearing no protection at all and climbing out of the basket?   Perhaps.  Perhaps not.   It does not necessarily address the issue of eliminating falls and there have been documented incidents where workers fell on lifts and were suspended but still sustained fatal injuries.  Effective free fall distances, with an anchor below one’s feet are also likely to exceed 6’.  Nobody will argue that a PFRS being used that effectively prohibits a worker from being able to climb up on the rails or leave the platform makes it less likely that the worker will fall from the lift.  However, this may not actually allow the worker to perform the work. 

Looks like someone lost the key?

Looks like someone lost the key?

The Elephant in the Room

The crux of the problem lies with why workers are climbing out of the lift in the first place.  Generally, it is because the lift does not allow them access to the area where they need to work.   Unless your crew is filled with a bunch of retired NBA centers, there is probably a need to leave the basket to get the work done.   In looking at these scenarios there are often other issues which factor into this limitation.  Perhaps the lift is the wrong size/type.  Perhaps workers have not properly oriented the lift to the work.  Perhaps a scissor lift is the incorrect means to access this work entirely.  There are a myriad of other possibilities but if we look at one of the biggest root causes in my opinion, is that workers are violating the rules because complying with the rules given the tools they are given to get the work done makes the work infeasible.  Do we really think that those same workers wouldn’t violate other rules like wearing PFP that would similarly keep them from being able to complete their work?  It seems more than reasonable that confining workers to the platform by short lanyards so they can’t climb out of the lift or access materials on the platform would only exacerbate the nature of the problem – namely that workers cannot complete or access the work.  Participation and compliance with a program that does not allow workers to actually do the work is an accident waiting to happen.   It is insane to think that adding more rules will solve the problem of people not following the rules in the first place.  

Accessory Work Platform Attachment

Accessory Work Platform Attachment

If we were able to provide workers a better means to access their work areas then we could potentially limit the risky behavior where workers are required to climb up and/or leave the confines of the basket.   Options include but are not limited to single person vertical lifts, knuckle boom lifts, platform ladders, scaffold systems, improved work sequencing, pre-assembly, tool extensions etc. There are also after market accessory platforms that can be attached to some lifts that have been developed and may potentially improve access challenges and keep people with their feet on the platform.

We can spend all sorts of efforts trying to develop practices to best use a wrench, modifying the wrench itself, training people how to best use the wrench and adding layers of PPE to protect their hands, face etc when using the wrench only to realize that perhaps a hammer was the better tool to drive the nail in the first place. There is a tendency by some safety professionals to equate more as better and unfortunately this is not always the case.  In the hierarchy of controls, PPE should be a last resort but unfortunately for many it is a first resort and little effort is made to eliminate or engineer out the hazards associated with workers accessing their work areas.

It should also be noted, that one of the original purposes of the anchor point on the work platforms was anticipating the need to drop guardrails to presumably better access work areas and thus requiring one to supplement with PFRS.  In practice however, we rarely see this being done and the only times workers really drop the rails is to be able to drive a lift through a doorway or other area of low clearance.   

Bottom Line

Is the use of a PFPS on a scissor lift a safety best practice?  The answer is yes, no and maybe.   Safety determinations are criteria dependent and are contingent on the specific variables present for the task required.   It requires a thorough understanding of the work, the inherent hazards and risks, relevant controls and values etc.  In some situations it may be most prudent to use a PFPS.  In other situations it may not.   It is incumbent on the competent person and safety professional to make a thorough evaluation of each situation and develop work rules and policies for each.  Gravity sucks but after all it is the law.  Hopefully this discussion has provided some additional insights into these operations to assist you as you wade through the challenges of providing the optimal working environment and controls for your workers.