What is a peak flow test?
Peak flow measurement is a quick test to measure air flowing in and out of the lungs.
The measurement is called the peak expiratory flow rate (PEFR). It’s also known as the peak expiratory flow (PEF). Peak flow measurement is mostly done by people who have asthma.
Peak flow measurement can show:
- The amount of air breathed in
- The amount of air breathed out
- The rate at which the air is breathed in and out from the lungs
During the test, you blow forcefully into the mouthpiece of a device. A peak flow meter (PFM) is used most often. This is a small handheld device made of plastic. A PFM is small and light enough to be used almost anywhere. It’s important to use the same PFM on a regular basis. The readings can vary between brands and types of meters. In some cases, the test is done in a healthcare provider's office or a hospital with a spirometer. This device has a handheld mouth piece that’s attached by cord to a larger electronic machine.