How to use a peak flow meter

A peak flow meter is a device that measures how quickly you can push air out of your lungs. A peak flow meter can help you check how well your asthma is controlled. Use it every day, and keep track of the results to help you and your health care provider learn about your asthma. This also may help you determine if your asthma is getting worse, even before you have symptoms. Here is how to use a peak flow meter.

Stand straight with your head up, and take a deep breath. Fill your lungs all the way. (Standing helps you get more air in your lungs.)

Place the mouthpiece in your mouth between your teeth, and close your lips around it. Be sure they form a seal around the mouthpiece. Do not put your tongue inside the opening.

Blow out as hard and fast as you can. You want to move the marker as far as you can with your breath, so concentrate on exhaling forcefully and quickly.

Set the meter back to zero, and repeat these steps 2 more times. If you cough or make a mistake, do not include this as one of your 3 tries. Record the highest of the 3 numbers in your peak flow diary.

Check which zone (green, yellow, or red) your peak flow number is in. Do what your provider told you to do when you are in that zone. This information should be in your action plan. If you are in the red zone, take your relief medicine immediately, and call your provider. If your symptoms don’t improve, or you can’t reach your provider, call 911 or the local emergency number right away.