Frequently Asked Questions on Peak Flow Meters/Spirometers


What is a spirometer?

A spirometer is an instrument that measures the capacity of the lungs indicating the volume and speed of air breathed in and out. The purpose of using a spirometer is to check the health and functioning of the lungs.

How does a spirometer work?

During a spirometry test, the customer is asked to breathe into the mouthpiece attached to the spirometer. The device measures the rate at which air is inhaled and exhaled as well as the lung capacity thus determining the speed/flow and volume/amount of air breathed in and out. The measurement unit is FEV1 which is Forced Expiratory Volume in One Second.

What is an incentive spirometer?

An incentive spirometer determines how deeply one can inhale and is generally used during treatment of lung conditions such as pneumonia. The test involves taking in slower, deep breaths for expanding and filling the lungs with air.

What parts make up an incentive spirometer?

Incentive spirometer has a breathing tube, an air chamber as well as an indicator. The breathing tube is attached to the air chamber with a mouthpiece at the end. The indicator can be found inside.

How to understand spirometer readings?

Follow the steps below to get an understanding of what the spirometer is telling you. Your doctor will of course do the diagnosis but this is just for your basic understanding.

  1. Take reading of the forced vital capacity (FVC)
  2. Take reading of the forced expiratory volume in one second (FEV1)
  3. If both FVC and the FEV1 are within normal range then this means your lung function is normal
  4. If FVC and/or FEV1 are decreased, this may be an indication of lung disease
  5. If FEV1/FVC readings indicate lung disease, check the % predicted for FEV1/FVC. If this is 69% or less then it suggests obstructive disease of the lungs