Green lights on plant machinery.

[Gordon A]

While suffering the road works on the M1 on our way to Wakefield, I noticed a number of diggers and a large dumper truck were carrying one green and one amber flashing lights on there superstructure instead of the usual two amber flashing lights.

What is the reason for the green flashing light?

 

Gordon A

Bristol

[Catkins]

It either means -

That they are all crewed by doctors, or more likely,

The green light is to allow the ground workers to differentiate between a road going vehicle and heavy plant.

 

The possible reason to need to tell the difference is that heavy plant on worksites have been involved in a few fatal incidents in the recent past, mainly as the plant has reversed someone has been in the wrong place at the wrong time.