- You will be seated in a clear plexiglass booth with your mouth on the mouthpiece and noseclips on your nose
- You will breathe normally and then a shutter will close. The shutter is closed for a second while you continue to breathe normally against the shutter
- The shutter opens and after breathing normally you will be asked to slowly blow out until your lungs are empty
- Then you will take a big deep breath in filling up your lungs completely
- As soon as your lungs are full, you will blow out as hard and as fast as you can until you are absolutely empty
- You will then take a breath in and come off of the mouthpiece
- The door will be opened until you are ready to do another effort
- You will be asked to repeat the test until there are three good efforts, which are repeatable
This test allows us to measure:
- Lung volumes - Thoracic Gas Volume (TGV) / Functional Residual Capacity (FRC)
- Total lung capacity (TLC)
- Expiratory reserve volume (ERV)
- Inspiratory capacity (IC)
- Inspiratory reserve volume (IRV)
- Residual volume (RV)
- Airways resistance (Raw/Sgaw)
- Spirometry at absolute lung volumes (FVC, FEV1 and PEFR)
This chart shows the measurements made during the test.
Learn more about the routine pulmonary function test.