Prior to working in this room will want to wear headphones, sound protection and protective glasses, because while the engine is working, there will be noise and dust which is harmful to the ear and the eye.
Previous work in this room must wear ear and eye protection, hearing protection. While the engine is noisy and dusty, which are harmful to the ears and eyes.
Before working in this room will need to wear protective headphones sound and protective eyewear. Because while the engine work are noisy and dust which are harmful to the ears and eyes.