How to Assess a Peak Flow Meter Reading

A peak flow meter measures how much air you can push out of your lungs with maximum effort, or the "peak flow" of your respiratory system. Regularly monitoring your peak flow can help you determine how your asthma treatment is proceeding.

Things You'll Need

• Peak flow meter

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Instructions

• 1

  Set the meter to the zero mark, or lowest point on the scale. Straighten your back as much as possible, either standing or sitting up straight, so that your breathing is as unhindered as it can be. Try to always use the same position when testing, for comparable and reliable results.

• 2

  Inhale as deeply as possible, then clench the mouthpiece of the meter between your teeth. Make a seal with your lips and blow into the meter as hard and fast as possible.

• 3

  Take the peak flow meter out of your mouth and examine the marker. Record this number.

• 4

  Repeat Steps 1-3, and take your highest number as the day’s peak flow.

• 5

  Look at your asthma management plan to interpret the numbers. If you're within the green zone, you have your asthma under control. The yellow zone means that your peak flow is at 50 to 80 percent of your recorded maximum, which could indicate a medical problem. If you’re in the red zone, you should see a doctor.