Like this?
We mount these on our helmets at work, much much much better than the Pelicans.
What I was dreaming about sometimes was a watch with a 5W dimmable background light…
Unless working with open fuel tanks, an intrinsicly safe light is not required. It comes down to tool control and accountability.
I would suggest not using your personally owned flashlight at work
If you can’t use your own light, and they haven’t approved the batteries for theirs…how do you see to work on the aircraft? The real bottom line is that the job must be done, and done correctly. The comment was made about wee hours of the morning, it’s obvious some light is going to be needed. Scary, actually, when you think about it.
Find a removable drop-in to use in the work light. 
This sounds like a situation for a head light, if common sense was allowed to prevail.
A headlight strapped to a personal hard hat wouldn’t even be noticed!
No personal lights allowed? All you can use are 2 D cell incan lights without batteries?
I have this sudden image of technicians working on UAVs by candlelight since that’s all that is allowed…
no open flames allowed on the job site with out a hot work permit 
And another fire extinguisher trained person standing fire watch.
I hear the voice of experience.
yeah… had to deal with that BS on a _few_occasions… my favorite was working down inside a hydro electric unit, with nothing but soaking wet concrete, mud and cast iron. need a hot work permit. on top of that we needed a hole watch, one that is usually playing a game on his iphone or sleeping preferred it seems.