Coloured lights on mobile plant

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jusme
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Coloured lights on mobile plant

Post by jusme »

Noticed that some of the mobile plant doing the M6 13-15 work has now sprouted purple strobe lights, as well as green and amber ones. Curious what they are for?

The green ones are apparently to indicate a safety belt is being used.

Googling suggests purple is for funeral processions :)
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traffic-light-man
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Re: Coloured lights on mobile plant

Post by traffic-light-man »

And there's me thinking there were GMC Doctors responding to emergencies in mini-diggers all this time... :wink:

I've seen a few Tarmac (the company, not the surfacing) surfacing jobs lately where they've fitted their plant with static blue lights that project a safe working distance on the floor that is mobile with the plant. I'm not entirely against that idea, it beats a blue flashing beacon!
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BlakeTehGreat2
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Re: Coloured lights on mobile plant

Post by BlakeTehGreat2 »

I don't know, maybe the M6 Toll is getting extended? :laugh:
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My local roads are the A5 and the A55.

From the SABRE Wiki: M6 Toll :

The M6 Toll is a bypass for the M6 through the Birmingham and Wolverhampton areas. Instead of passing through the West Midlands conurbation, it runs to the north in existing road corridors alongside the A446, A38 and A5, and incorporates part of the M42. It was originally allocated the number A446(M), though due to its non-standard number, the number M600 is used for administrative purposes.

An extension to the route of the M6 Toll between

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BeenEverywhere
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Re: Coloured lights on mobile plant

Post by BeenEverywhere »

We had blue (might have been purple, I'm colourblind) on the forklifts in a yard I worked in briefly. They were to distinguish plant from vehicles, and to show that the machine was working or moving (not just sat with the engine running).
Been everywhere... can't remember any of it

Was fun though :laugh:
darkcape
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Re: Coloured lights on mobile plant

Post by darkcape »

Green flashing lights: seatbelt engaged
Blue/white flashing lights: plant in motion (mostly for larger plant like cranes where it's not necessarily immediately obvious they're moving)
Purple flashing: slew restrictions active (electronic controls to limit the movement of machine e.g to stop it swinging out into a live lane)
Blue/green/red/purple static: exclusions zones for ops, as stated above Tarmac's plant mostly uses blue or green LEDs to project markers onto the ground for ops to stay clear of.

Cranes also have a traffic-light system for the rated capacity indicator I.e how much load the crane has. Amber when the crane is getting close to it's working load limit and red when it is achieving that limit. Sometimes these are in-cab but large cranes usually have external indicators too.
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Barkstar
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Re: Coloured lights on mobile plant

Post by Barkstar »

darkcape wrote: Sat Oct 03, 2020 08:53 Green flashing lights: seatbelt engaged
Blue/white flashing lights: plant in motion (mostly for larger plant like cranes where it's not necessarily immediately obvious they're moving)
Purple flashing: slew restrictions active (electronic controls to limit the movement of machine e.g to stop it swinging out into a live lane)
Blue/green/red/purple static: exclusions zones for ops, as stated above Tarmac's plant mostly uses blue or green LEDs to project markers onto the ground for ops to stay clear of.

Cranes also have a traffic-light system for the rated capacity indicator I.e how much load the crane has. Amber when the crane is getting close to it's working load limit and red when it is achieving that limit. Sometimes these are in-cab but large cranes usually have external indicators too.
And if all are going at once then the driver is listening to the Bee Gees on his headphones :coat:
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traffic-light-man
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Re: Coloured lights on mobile plant

Post by traffic-light-man »

I don't really understand the necessity behind the green flashing light, but I suppose it's an incentive to the driver to do what they should be doing anyway...

What I really don't understand is why a slew limit needs to be signalled to everyone around? I might be able to make sense of it if it flashed while it was actually slewing, but just when the limiter kicks in seems odd to me. I'm not arguing against it here, I'm genuinely interested to see the benefit of it being signalled.

Having said that, I regularly drive several 'cherry pickers' that have a blue strobe on the bottom of the basket that flashes when the 'something's wrong' alarm is active (i.e., weight limit exceeded, ground level warning etc), which always seems a bit strange to me given it's mainly the driver who is in the basket that needs to know. The primary safety feature in this instance is that the machine will just stop when the alarm is triggered, though, so I suppose the light can make others aware of why you've just stopped.
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darkcape
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Re: Coloured lights on mobile plant

Post by darkcape »

traffic-light-man wrote: Sun Oct 04, 2020 09:28 I don't really understand the necessity behind the green flashing light, but I suppose it's an incentive to the driver to do what they should be doing anyway...

What I really don't understand is why a slew limit needs to be signalled to everyone around? I might be able to make sense of it if it flashed while it was actually slewing, but just when the limiter kicks in seems odd to me. I'm not arguing against it here, I'm genuinely interested to see the benefit of it being signalled.

Having said that, I regularly drive several 'cherry pickers' that have a blue strobe on the bottom of the basket that flashes when the 'something's wrong' alarm is active (i.e., weight limit exceeded, ground level warning etc), which always seems a bit strange to me given it's mainly the driver who is in the basket that needs to know. The primary safety feature in this instance is that the machine will just stop when the alarm is triggered, though, so I suppose the light can make others aware of why you've just stopped.
These ideas were introduced before I started in the industry and so I may be wrong on original reasons...but the lights for slew restrictor & seatbelt are signalling that two significant safety features are engaged to others in the vicinity, that the machine can't check itself, but enables anyone else in the area to check/be confident the procedures are being followed.

Most modern kit, as you'd expect, comes with a myriad of features designed to ensure the machine is used correctly. As with your cherry-picker example, most plant will automatically cut out if it exceeds the limits it is designed for....cranes stop lifting, excavators stop lifting etc, the cherry picker cuts out if its out of balance. Large machines won't let you move them unless they have warmed up correctly, for some plant this could be a 20-minute wait!

With seatbelts, the machine can't check - as ops often clip in the belt (to engage the light), and then sit on top of it. With my safety hat on, if I'm walking about on site and see a machine operating but the green beacon isn't on it either means the beacon is faulty or the op isn't buckled in, I'd go over and ensure they are working safely - the same goes for slew restrictions. Slew restrictions also means the machine way not make movements you're expecting e.g rotate "the long way around e.g 270degrees" because its movements may be restricted.
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avtur
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Re: Coloured lights on mobile plant

Post by avtur »

I have been watching the dual carriage way development of the A2300 near where I live, on countless occasions over the last 18 months I've seen plant vehicles displaying high intensity blue lights, they are constant, not flashing. For all that time I've been meaning to find out about the significance of these blue lights. Recently I was stuck in traffic along side these road works and started talking to one of the machine operators, so I took the opportunity to ask him about them.

It appears the lights are part of something called the "5 + 2 Initiative" which is designed to keep people and moving plant vehicles apart on work sites. The guy told me the basics in the time we were chatting and I've since found out a bit more. Historically falls from heights have been the biggest killer on UK work sites, however in more recent years people being run over by moving vehicles has overtaken falls from heights as the biggest killer.

"5 + 2" is designed to identify an area 2 metres to each side and 5 metres ahead (in the direction of travel) of a moving plant vehicle. The blue lights have a high intensity tight beam which is aimed to strike the ground at the appropriate distance from the vehicle, therefore defining a clear area around the vehicle which people should steer clear of. The lights are sufficiently bright that they can be seen in daylight.

No doubt some will think think is an over engineered solution to the problem, but while you might like to believe that an individual's sense of self preservation would be enough to keep them out of harms way, serious injuries and fatalities demonstrate that a person's sense of self preservation cannot be relied upon to keep them alive in a work environment laden with hazards, hence schemes like this are developed.

Certainly in the private sector I have seen huge amounts of pressure, and resource, applied to developing preventative programs (such as this) in an attempt to save people from themselves. I don't doubt that some might prefer a more Darwinian approach and would prefer that people suffer the consequences of their actions or lack of awareness.
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michael769
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Re: Coloured lights on mobile plant

Post by michael769 »

traffic-light-man wrote: Sun Oct 04, 2020 09:28 I don't really understand the necessity behind the green flashing light, but I suppose it's an incentive to the driver to do what they should be doing anyway...
For me it's an admission that the site's operator does not trust it's staff to properly use safety equipment.

I will leave it as an exercise to the reader to decide if employing staff they do not fully trust to operate heavy machinery is the action of an organization that really cares about safety (as opposed to caring about looking like it does!).

As mentioned the lights are easy to defeat (as would an interlock).

Slew lights have genuine value as they indicate (when not lit) to others on the site that the vehicle needs a wider than normal safety margin to the sides. While the lack of light to indicate a hazard, at first glance, seems counterintuitive it provides an effective fail safe in the event of lamp failure. It is not uncommon in industrial environments for lights to indicate a safe state rather than the converse.

Ground indicator lights have the benefit of being easy to understand and explain to people on the site who may not be familiar with the capabilities/quirks of the equipment concerned. Track laying vehicles, for example, move in a manner that is very unexpected to people who are only used to driving wheeled vehicles.

While expecting people to be aware and look after themselves is perfectly reasonable, expecting people to understand and predict the behaviour of equipment that they have little experience of in their day to day life is quite unreasonable.
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KeithW
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Re: Coloured lights on mobile plant

Post by KeithW »

michael769 wrote: Mon Jan 24, 2022 16:34
traffic-light-man wrote: Sun Oct 04, 2020 09:28 I don't really understand the necessity behind the green flashing light, but I suppose it's an incentive to the driver to do what they should be doing anyway...
For me it's an admission that the site's operator does not trust it's staff to properly use safety equipment.

I will leave it as an exercise to the reader to decide if employing staff they do not fully trust to operate heavy machinery is the action of an organization that really cares about safety (as opposed to caring about looking like it does!).

As mentioned the lights are easy to defeat (as would an interlock).
Any site manager who chooses to 'trust' his operators to the extent of not bothering with customary warning lights is likely to find himself in deep trouble if something goes wrong. Omissions of recommended equipment in case of an injury accident will attract the full attention of the HSE and draw accident and injury lawyers like flies to honey. Even in the 1980's we used them on construction sites when large dump trucks, bulldozers and cranes were moving although they were amber at that time.

Defeating warning lights is like wearing an empty parachute pack, pointless and potentially fatal if things go wrong. As someone who worked on construction as a manger I have no sympathy with anyone who does such a thing, I would fire him on the spot.
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