When you hire a contractor to work on a home improvement project,Bathroom upgrades make sure that he is holding a current license and that he has insurance for his employees. This is important for your protection, in case you have a legal dispute about the quality of the work. In addition, if his employees are not covered by his insurance, you might be financially responsible for any injuries that an employee incurs, while he is on your premises.
I think that you will take responsibility not only for the workers' health in the execution of the order but also for the quality of their work. A few months ago, I was doing repairs in my house, including the bathrooms, and I was very responsible for choosing the specialists. The only thing I did myself was installing https://www.radiatoroutlet.co.uk/bathroom-radiators/towel-rails, as I could trust myself to do it.