A respiratory therapist will take you to a room to test your lung function, or how much air you can blow out and how fast you can blow it out. During the test, you will wear nose plugs and blow as hard as you can into a machine. Your parent or guardian is allowed to be in the room with you to cheer you on.

PFT's do not hurt, however they are hard work because you must do the best you can when being tested or the doctors can't accurately decide the best way to make you better.