What is a "peak flow"?
A “peak flow” is a lung function test which tells us how quickly you can blow air out of your lungs. It is a quick and simple test you can do yourself using a peak flow meter, a small handheld device.
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What is a "peak flow diary"?
A healthcare professional may ask you to complete a “peak flow diary”. This is when you measure and write down your peak flow reading several times a day for a few weeks. This helps us to assess how your lung function might change in different places, such as at and away from work. Completing a peak flow diary can be repetitive, but it is very important to help us diagnose conditions such as occupational asthma.
What do I need to complete a peak flow diary?
- Peak flow meter - please ask your relevant healthcare professional
- Instructions and how to send results - this has also been copied below
- Weekly diary template - download in any of following formats: PDF / Word / Excel (spreadsheet)

