06.09.2019

Harness saves boom operator

An articulated boom lift over turned earlier this week in Victoriaville, Quebec, Canada – around halfway between Montreal and Quebec City – on Tuesday morning.

The unit appears to be a JLG 800AJ, its riser or tower boom was retracted and raised to its midpoint, while the upper or main boom was also retracted and raised to and angle of around 40 degrees above horizontal. One man was in the platform, when the machine tipped rearwards, landing on its counterweight.
The machine, an 80ft boom lift overturned rearwards


The man in the platform was catapulted out of the basket, but thankfully was wearing a harness and lanyard. It seems there was some contact with the power lines as he went over the top. He was left dangling from his harness at a height of around five metres for some time.
The local fire department arrived but had to wait for the power to be shut down and checked, firemen then used a rescue ladder platform to rescue the man, said to be in his mid 30s from his harness.
The fire department rescue the stranded operator


What caused the overturn is difficult to gauge, it does not appear to be related to the ground giving way below any of its wheels, and the machine was working within its safe working range.

The ground also looks to be fairly level. Could a failed oscillating axle lockout or punctured pneumatic tyre have been the cause? It shouldn’t cause this to happen on level ground. Hopefully we will learn the cause so that others might benefit. The man is seriously hurt but is said to be recovering in hospital.
It is hard to see what might have caused the machine to tip

Comments

Auld Yin
800AJ should have foam filled tyres. Looking at the pictures there's a slight slope towards the road and the machine seems to be close to the building. The wheels are turned to the right and turntable slewed 90 degrees so front axle is locked and drive inhibited. If op was trying to travel forward he'd be first of all looking at the drive enable switch and not necessarily concentrating on what the machine is doing. He may have travelled a few feet before turning the steering which may have led to a wheel lifting due to the axle lockout. If the boom contacted the building whilst turning towards the building it may just be enough to cause the machine to tip onto the ballast. Also looking at the amount of oil/dirt on the chassis below the turntable I'm guessing maintenance may not be as it should and there's a possibility of a machine failure. It doesn't take much to damage or move the ground control module which contains the tilt sensor possibly causing it to be off by a couple of degrees.

19 Sep 2019

Pemby
Yeah, I get what you say, but in a MEWP, aside from 'keep the idiot in the basket' there's therefore technically zero protection from being flung not just out of the basket but then onto the ground below by external forces - ground give way, boom hit by vehicle, etc, 'anchor for restraint not fall arrest harness' is stupid. hell, mechanical failure of say, the hydraulic ram that controls basket tilt angle that acts in sync when you raise a boom, if that goes... and then a 'restraint harness anchor point' really is just good for restraint and not for fall arrest, and you're say, at the highest you can go on a, say, 40-foot boom, sorry bub, you're dead. this is one point at which there are MANY factors that could lead to it - so not just machine maintenance, good operator and properly segregated from other plant and vehicle movements, and decent flat level ground with zero debris... don't think I've ever seen such a site.

10 Sep 2019

Access Jim
It does appear Eric that your provided info is correct.
This does indeed differ from UK HSE and IPAF guidance (which is what I was referring to :))
I will still state that most manufacturer mewp anchor points are still mainly designed for restraint only and this should always be clarified with the machine manufacturer. Anchor points for fall arrest must be designed to withstand a shock load of 6kn (600kg).
Best practice is always to follow the hierarchy: Avoid, Prevent, Minimise.

9 Sep 2019

Sherm
New thought came to me, supported by the imagined feeling that worker must have had when the lift base went “on tilt”! If that machine has driving controls in the basket he might have driven the rig against the building and when it started to lean he lost control or was going to fast to stop the accident. So now the question occurs did he have a banksman on the ground to guide his movement or was he working alone?

9 Sep 2019

Eric_L
Sorry Access Jim, but you are wrong.
Different standards around the world mandate different requirements, for example Aus/NZ require the use of fall arrest systems in MEWPs
http://www.ewpa.org.nz/Resources/Documents/Safety%20Bulletins/Harnesses%20in%20MEWPs%20-%20April%202012%20v2.pdf
As for manufacturers, the anchor points are tested to normative requirements, which are a force value. The don't specify a particular system.
Both systems have their advantages and disadvantages, but are suitable for use with MEWPs. Just a question of the right tool for the job.
Having tested a fall arrest unit with body harness, attached to the back, I can say they work quite well, apart from the "wedgie" you get from the leg straps.

9 Sep 2019

Access Jim
The ignorance and lack of knowledge that some people have on this site always amazes me.

Pemby, contact the machine manufacturers and they will tell you that the anchor points are restraint only and NOT fall arrest

This is not my 'personal' opinion it is FACT.

Here is a section taken from the UK HSE website:
https://www.hse.gov.uk/foi/internalops/ocs/300-399/314_20.htm

Appropriate fall protection equipment

14 Definitions :

(1) Fall arrest - This stops a person after they have fallen
(2) Work Restraint - This stops you falling in the first place, by preventing you from getting in to a position where you can fall. Work restraint is sometimes incorrectly called fall restraint or referred to as work positioning.

Work restraint systems

15 Work restraint will be the typical system used in the carrier because most anchor points in carriers are only rated for work restraint and the effectiveness of these systems is not height dependant. A typical work restraint system normally consists of a full body harness and lanyard with no shock absorber because the person will not get into a fall arrest situation. The lanyard length should be set or adjusted such that the user cannot get into a situation where fall arrest is required, this applies to fixed length, adjustable length and retractable (inertia reel) type lanyards. A waist belt should not be accepted as a full body harness will distribute any impact forces better.

Fall arrest systems

17 A typical fall arrest system normally consists of a full body harness and a lanyard with some form of inline shock absorption capability. Use of this type of system should not occur that frequently as most anchor points are not rated for fall arrest and therefore could fail. Where this type of equipment is found in use confirmation of the MEWP's anchorage compatibility should be sought.The user should always confirm with the MEWP manufacturer that an anchor point is suitable for fall arrest. Anchorage points should be designed and tested as being suitable for fall arrest

18 Additional concerns have been raised that the forces generated during fall arrest could cause an overturn, currently a European standard does not exist for testing the effects of dynamic loading from fall arrest on MEWP stability (HSL research is planned) and the effectiveness of fall arrest systems is height dependant.

IPAF states:

Boom type platforms

When working from a boom- type Mobile Elevating Work Platform (MEWP), it is strongly recommended that a lanyard short enough for the wearer to be restrained within the platform be used. The lanyard may contain an energy-absorbing device, provided it is short enough to restrain the wearer within the platform. This includes Static Booms (1b) and Mobile Booms (3b)

7 Sep 2019

Pemby
Jim, that's weird as from a safety perspective (and various news articles on here about incidents), that lanyard is supposed to be able to hold the weight of the operative suspended, in the event of any of a various type of situation that we have heard on here where people died because they didn't wear one - the MEWP tipped over and the operative fell out, or simply driving over a bump and the platform bouncing around flung the operative out onto the ground, etc. If the points on the MEWPS are only meant to work in concert with VERY SMALL lanyard in "yeah you are not reaching out of the basket around this piece of steel to bolt another to it" and not as a point for any sort of Fall-Arrest lanyard, in other words, break off, then what is the point of actually using a harness if the machine physically wont stop you from being flung off from it?

An example, based on your words then, would be, someone anchored in to the platform by his 1 metre lanyard, using a large truck-mounted unit, at the top of some, say, very tall lampposts - and I mean tall, the old ones that used to be on the liverpool-birkenhead tunnel entrances for example - and while a crane gets the book into position above the lampost, say, one supplied by ainscough on the first visit but roadcraft thereafter for reasons I never knew-I mean, reasons I wont bother to think up - say, there's a little jerkiness in the controls when using any speed above 'minimal' on the machine some sort that never actually had- Ahem. So there I am - I mean, this operative, barely managing to reach around because his lanyard is, naturally, restraining him from physically moving outside of the basket. so far so good. but the 'bump' causes a catapult situation, and I-I mean the operative, is flung out, but I-He should be fine, afterall, wearing a harness that has a lanyard that is actually attached at the properly designated point of the basket for such-oh, I'm dead because - I mean, this operative is dead because that anchor point failed, as it isn't meant to hold the weight of a person. MEWPS should therefore not be used as they dont actually have a feature, such as, a lanyard anchor point, capable of acting *as* an anchor point.

Now, I thought maybe you meant MEWP like a scissor lift which goes up and not out, but still some can be driven (at slow speeds) while extended, and all it takes is to suddenly drive into a little rut (say a gap in the concrete floor acting as a rain run-off drain for a train station platform?) and that can move about, a lot.

Not that "I" have been in a scissor lift with tortoise-speed movement capability at near or full height extension capacity, because no such machine would exist in a world with lanyard anchor points that ARENT strong enough to hold the weight of a person.

7 Sep 2019

Sherm
Jim, I stand corrected with appreciation for your wisdom that seems to be much greater than mine. I plan for more study plus review of the safety information that came with my harnesses and lanyards. I may need to purchase different h’s and l’s for better margins of safety. We must practice safety every minute one minute at a time.

7 Sep 2019

Access Jim
Sherm, you clearly do not understand the principal of a restraint lanyard system, which is the only system which should be used in a mewp.
The purpose which is to restrain (hold back) and keep the operator within the basket and not expose the operator to a 'fall' situation.
Another important factor which some operators do not understand is that anchor points in mewps are ONLY desisgned for restraint purposes and not for fall arrest which is what you are describing.
Applying a 'shock load' or 'fall arrest' to a restraint anchor may cause it to break as they are not designed for that purpose.
Maybe some more training is required?

7 Sep 2019

Sherm
To Access Jim and other readers, thanks for your time to join the fray on this incident. Yes I surmise my two lanyards should be shorter than they were manufactured. But in my humble opinion, in a fall you would want to swing clear of the basket. Both my harnesses, different brands, have the metal safety ring on the back. Every accident I read about concerning someone thrown from a basket I wonder which position I’d rather be in if it was me..face down or face up. I lift weights in daily exercise for upper body conditioning but I don’t know how long I could sustain my consciousness if the safety ring were in front. I’d be very thankful to have saved another fall to Earth. Twenty years ago as a tree climber I fell 20’ or 5-6m to solid dirt from a tree limb because I forgot to tie-in my climbing saddle to the tree.I was in my apprentice years and working alone. The right side of the pelvis was shattered, hip was broken and few other hurts. A titanium hip put in in 2010 has been wonderful. Maybe a surviving aerial warrior who has fallen wearing a harness will chime in here and tell of their preference(s). We all learn from each other and from experience. Ciao!

7 Sep 2019

Access Jim
Sherm, do you know the purpose of a safety harness on a mewp is to restrain you and keep you within the basket? The lanyard should be kept as SHORT as possible at all times (eg 1-1.25 metres)
It is a bit worrying to think you would want to face down while hanging by the lanyard!
Training and education is the most important thing here :)

7 Sep 2019

Sherm
Editing my post above: outriggers furnished on 4-wheeled MEWPs to provide stabilization. The NO microswitches are Normally Open but once the pads are pressed to mats or solid surface (Earth) the switches close to form a circuitous loop to the power control box (brain) for safety. I thought about the worker today imagining the shock he must have felt when the lift tipped over. My harness has the loop on the back straps. That would make me face down while hanging by the lanyard. I bet he’s feeling some aches and pains from this but so grateful his life was spared.

7 Sep 2019

Sherm
In my 18 years of lift work on trailer lifts with outriggers I have noticed a common problem with four-wheeled MEWPs...no outriggers to stabilize a lift. I’ll probably get a lot of flak about this for sticking my foot in my mouth. Perhaps a graduate engineering student would pick up on this and write thesis on the connection or correlation. My Niftylift. TM40 has outriggers and NO microswitches at each pad axle. If just one pad gets loose it shuts down and will not move until the ground man checks the four pads and corrects the set. If a four-wheeled lift like this one has safety’s built in at the base for level acumen at both directions why didn’t it sound an alarm or stop the operation for corrective action? Whatever flaws we have in our equipment industry-wide we as an industry need to wake up and change the way we train, certify, rent out, install and use our equipment. I won’t apologize to anyone for my bold aggressive aim to stop accidents we truly could prevent.

6 Sep 2019
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