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Peak Flow Meters

A peak flow meter is an inexpensive, pocket-sized device that measures peak expiratory flow (PEF), or how fast a person can breathe out. To measure PEF, the person takes a deep breath and then blows into a tube on the peak flow meter as hard and as fast as possible. This can be done at home.

Peak flow meters come in many shapes and sizes.

By	Healthwise Staff
Primary Medical Reviewer	Adam Husney, MD, MD - Family Medicine
Specialist Medical Reviewer	Sue Barton, PhD, PsyD - Behavioral Health
Last Revised	August 26, 2011

WebMD Medical Reference from Healthwise

Last Updated: August 26, 2011

This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.