What an interesting subject!
Not railway related but in 1969 I was on road tankers and as i had no vehicle of my own I did hol/sickness cover.One day I had to take an AEC MK3 8 wheeler and work out of BP Chemicals at Saltend,Hull.The wagon belonged to "Shekky Les" and after a few miles there was a strong smell of piss(can I say that on here?).
I found out off another driver that "Shekky" didn't like stopping so he used to pee in a bottle whilst driving and empty it down where the ratchet handbrake gaiter was on the floor,straight onto a hot oil-smeared engine.This, combined with a hint of diesel and gloves covered in what you were carrying last like Acetone etc. made for an interesting combination.
The fitters were forever freeing the mechanism off as it was always seizing up!
What price H and S in them days?