Ventilation helps to:
- Provide adequate oxygen to the air in the space,
- Control atmospheric contaminants,
- Prevent fire and explosion hazards, and
- Control heat and humidity.
Once it has been determined that the confined space contains a harmful atmosphere, the next step is to clear it. Ventilation blows out oxygen-deficient or contaminated atmospheres and replaces harmful vapors with clean, fresh air. Make sure to ventilate the space thoroughly so that there are no contaminated pockets left, and then test the atmosphere again.