The atmosphere in a confined space is an unknown entity. You should always test it before entering. Use a direct reading instrument that will identify any toxic air contaminants. It should also provide information about the level of oxygen, and flammable gas.
Test the Atmosphere in Confined Spaces
By Steve Theunissen , August 9, 2016
Takeaway: When going into a confined space, always test the atmosphere to ensure it is safe for entry.
Attention Safety industry professionals - sign up here to join the safety movement