in the UK and most of Europe
AFAIK, there's no need for EASA Regulations, because other regulations will be in force, eg Factories Act in the UK, Health & Safety Regulations etc. Aircraft hangars are not exempt; why should they be? Just like the USA. as
riff_raff pointed put.
(CAP 716 Chapter 5 is not much help; just some vague generalities that a good working environment is a good idea.)