Do not enter or lean into a low-lying confined area until it has been completely aired out and tested. Take Personal Precautions After working with MC, always wash your face and hands before eating. Alcohol can lower the amount of MC needed to cause health problems. Avoid situations that might result in overexposure. If engineering controls and work practices do not reduce MC exposures to an acceptable level, workers must wear supplied-air respirators.
Respirators are the least preferred method for controlling employee exposure.
Supplied-air respirators must have a clean air supply through the use of compressed air tanks containing air meeting at least the requirements for Grade D breathing air, or a breathing air type compressor with the air intake located in an area with a clean air supply. Filter cartridge respirators cannot be used because MC can pass through available cartridges leaving respirator wearers unprotected.