Purging & Inerting

Purging is a process that rids the confined space of its current atmosphere and replaces it with an acceptable, safe supply of air. However, purging is a short-term solution; it is typically used to ready a space for ventilation once the air quality reaches acceptable levels.

Inerting is a process that adjusts the atmospheric conditions within a confined space. This process uses inert gases, such as argon, nitrogen, or carbon monoxide, to decrease the oxygen content of the air. As mentioned previously, a higher oxygen level presents a greater risk of fire or explosion. Decreasing the oxygen level presents less chance of a fire or explosion, but because oxygen levels in the air may dip below the safe range for humans, workers in the confined space must wear appropriate respirators to ensure their safety.

While performing any of these corrections, workers should direct the exhaust from the space away from people so that people outside the confined space are also safe. It is important to test the air again after corrections have been made, before anyone enters the confined space, and to continue monitoring the air quality the entire time work is being done.

To learn more about Confined Spaces visit our Canada Confined Space Online Training web page.