English to Spanish Tech/Engineering Construction / Civil Engineering Security Standards

I am translating a Health and Safety Manual and these two job occupations appear on the text:
Burners and welders will not be permitted to wear polyester or nylon clothing.

Wider context: No shorts are to be worn on projects. All employees, except welders and burners, must tuck shirt tails inside trousers. Burners and welders will not be permitted to wear polyester or nylon clothing

I asked someone who knows about Site Safety Standards, but he said in my country that job is not known.
There only translation for Welder and cutter.