Air Quality Testing

Before entering any confined space, you need to determine if that space is considered a confined space. To do this, ensure that the confined space hazard assessment and control program has been followed; click here for more information.

The next step, before entering the confined space, is to test the air from outside the confined space.  A trained worker, using detection equipment, should do the air quality testing.

The testing equipment should be maintained for accuracy and a sample test should indicate:

  • the oxygen content is within safe limits - not too little and not too much
  • a hazardous atmosphere, such as toxic gases, flammable atmosphere, is not present
  • ventilation equipment is operating properly

Testing the air quality may need to be ongoing during the work as conditions can change while workers are inside the confined space.


Image courtesy of CCOHS