Lung function testing

What to expect if you are referred for lung function tests at St. Paul's Hospital.


Lung function tests determine how well your lungs work. 

Tests can measure:

  • How much air goes into and out of your lungs.
  • How much air goes from your lungs to your blood.
  • How well your lungs work during exercise.

These tests are done in our Pulmonary Function Lab. Pulmonary is a medical term used to describe anything to do with your lungs.

You will need a referral from your doctor or nurse practitioner for these tests. Once we receive your completed referral, we will contact your doctor or nurse practitioner with the appointment information. That person will contact you with those details.

Preparing for the test

The day before your appointment, we will phone you with some health screening questions. 

Before your appointment, we'll check the medications you're taking for your breathing problems. If necessary, we'll tell you to stop taking any of them.

On the day of the test


  • Arrive 15 minutes before your scheduled appointment.
  • Wear loose clothing and comfortable footwear such as sneakers or running shoes.
  • Bring your BC Services Card or other government-issued photo ID.
  • Bring a list of all your breathing medications.
  • Keep taking all the medications your doctor prescribed. If you need to stop a medication for the test, we will tell you before.

Do not:

  • Wear perfume, aftershave, or other scented products.
  • Do any physical exercise immediately before.
  • Smoke within one hour of your test.
  • Eat a large meal within two hours of your test.
  • Consume alcohol within four hours of your test.
  • Use your inhalers unless you start to have significant respiratory symptoms.

During the test

The respiratory therapist (RT) will introduce themselves. They will also introduce any support staff helping with your procedure.

The RT will review your medical history. They will explain the equipment they will be using and answer any questions you may have. Pulmonary function tests generally require you to perform a variety of breathing types and maneuvers.

Appointments are approximately 30-90 minutes long.

Support for Indigenous Peoples

The Indigenous Wellness Liaison Team is here to support your health journey. Team members offer cultural support and healthcare advocacy. Learn more below or call them at 604-682-2344 ext.62937 or email

  • Indigenous wellness services

    The Indigenous Wellness Team at Providence is available to support Indigenous patients and their families. We are here to coordinate culturally safe wellness supports and services.

Medical & professional referrals

Please complete the referral form below and fax to the Pulmonary Function Lab - 604-806-8544