Breathing Tests – Peak Expiratory Flow Rate

Peak flow meter

There are two commonly used breathing tests: 

  1. Peak Expiratory Flow Rate.
  2. Spirometry.

Peak Expiratory Flow Rate

Peak Flow measures how quickly the person can breathe air out of the lungs. It is performed using a peak flow meter.

  • This is a handheld device which the person blows into as hard and as fast as possible, ensuring a good seal with their mouth and the mouth piece.
  • It is usually used to monitor asthma.
  • If their asthma has deteriorated or is flaring up then the peak flow rate gets lower.
  • A chart to record regular measurements of peak flow over time can assess the response to acute or long term treatment.
  • The rate should get higher and less variable once asthma is controlled.