Numbers On A High Viz

[webbo3]

I don't know if anyone has an answer but across the road from my hospital they are building some student accommodation, watching the builders I've noticed they all have a high viz and each one has a different number, I've just started watching 24 hrs in A+E and they were in a helicopter flying over London during the opening credits and I saw the same thing, builders with numbered Hi viz waistcoats.
Any idea what the numbers are for. ?

[chelle7272]

Possibly for ID in case of an accident?

[davebro]

It's the number of hours they have to do unpaid work!

[Buenchico]

It's probably so that they can easily be identified for safety reasons. For example, a safety inspector might arrive on a site and looks up at the scaffolding to see a construction worker perform his job in an unsafe way. When he manages to locate the foreman, to express his concerns about the matter, it doesn't help much if his reply to "Which worker was it you saw?" is just "I'm not sure. It was one of those fifty guys out there. He was wearing a hi-vis jacket". It's a lot better if he can say "You number 31 is behaving like an idiot. He'll either kill himself or someone else very soon".

[Hopkirk]

"I am not a number, I am a free man!"

[tonyav]

No you're not No 6 ^^^^^

[douglas9401]

It could be a new elaborate lottery game.

[douglas9401]

Let's call it Cash Builder