You need to know your child's personal best peak flow number to help control your child's asthma. Changes from
child's personal best can help you see how well your child's asthma is under control. These changes also can let
know when your child needs medication and when your child needs medical care.
If you don't know how to find it, click here for an
Note: The minimum height for this calculator is 44 inches.
Each person's asthma is different, and each person's personal best peak flow number is different.
Children's peak flow numbers typically vary by height, but even among people of the same height, weight
and sex, peak flow numbers can differ.
Here's how to determine your child's personal best peak flow number:
Talk with your child's doctor before measuring your child's personal best peak flow number. He or she
other instructions or suggestions, based on your child's condition.
Once you know your child's personal best peak flow number, you can use this calculator or ask your
to help determine the values for your child's Green, Yellow and Red Zones.
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Since your child's height is , his or her estimated peak flow meter value is .
How much your child's daily peak flow differs from his or her personal best is
described as being in the Green, Yellow, or Red Zone. Here is a breakdown of each zone.
This calculator is not intended to replace the evaluation of a health care professional.