Identify Green, Yellow and Red Zones


The peak flow charts on this website have three bands, called the Green Zone, Yellow Zone and Red Zone.

Your peak flow readings will fluctuate every day. A health person without asthma peak flow readings would fluctuate by a small amount. There are many factors which can affect your peak flow reading. The aim of the coloured zones is to identify if the fluctuations are within an acceptable level.

Green Zone

You should aim to maintain your peak flow readings within the green zone. The green zone shows that your peak flow reading is within 80% to 100% of your personal best peak flow reading.  If your readings are within the green zone then you should be relatively symptom free and should continue your current asthma treatment plan.

Yellow Zone

The yellow zone shows that your asthma is getting worse and you need to temporary increase your asthma medication. If your peak flow readings do not return back to the green zone, then you may need to change your asthma treatment plan. Please consult your doctor or asthma nurse.

Red Zone

The red zone is the danger zone. If your peak flow readings are within the red zone then you need to take immediate action. Please consult your doctor or asthma nurse.

April 11, 2012 at 9:16 am | Graph | No comment

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