How to Read a Peak Flow Meter

Peak Flow Meters are designed to measure the amount of air that can flow through the lungs, or the peak expiratory flow rate (PEFR). For those who suffer from asthma, the device helps keep an eye on the airways so that physicians can determine how severe the asthma is and which treatments will be most appropriate. In the event that you should need to use a peak flow meter at home, it is important to understand exactly how it works.

Things You'll Need

• Peak Flow Meter

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Instructions

• 1

  Set the meter to zero or its lowest possible value before you begin. Starting with the same value each time is important for achieving consistent results.

• 2

  Blow into the meter according to the unit's specific instructions. You will likely need to stand up straight and breathe deeply before exhaling into the mouthpiece. If you are taking someone else's reading, such as a child's, remind them to place their tongue under the mouthpiece so that it does not interfere with the passing of air into the meter.

• 3

  Record the number on the device and then repeat the processing of breathing deeply into the meter twice more. Write down the number or reading after each breath. A digital peak flow meter will simply display the reading on its interface. For most other devices, you should watch as the marker or indicator moves along a scale and record the highest number that it reaches or the point where the marker stops.

• 4

  Note the highest of the three readings and keep that information so that a physician can evaluate it. In general, there is no baseline or "normal" peak flow measure. By using the meter twice daily for up to three weeks when your asthma is under control, you can get an idea of what your personal normal reading should look like. If you notice an increase or decrease from your personal normal value, it is time to contact a healthcare professional.