Understand Peak Flow Charts


The Peak Expiratory Flow (PEF) is a measurement of how much air flows through the airways in the lungs. If the airways are narrowed, as in episodes of asthma, then the readings are lower.  By recording and charting these readings we can better understand your asthma.

There are four main patterns of peak flow charts that are suggestive of asthma.  But first we will examine the chart of a healthy person.

Good Chart

The above chart shows readings with small variation in readings. This chart has a percentage change in PEF of less than 20%. This type of chart is seen in people who have well controlled asthma or those who do not have asthma.

The important results that will help doctors and asthma nurses to diagnose asthma from the peak flow charts are:

  • A variation between readings of more than 20%
  • An increased difference between the morning and evening readings
  • An early morning dip in the readings

Large variations

The above chart shows a large variation in peak flow reading from day to day. A chart like this would help to confirm the diagnosis of asthma. For someone with asthma a chart like this would indicate poor control and more treatment is required.

Morning Dips

A peak flow chart showing early morning dips in the readings would help to confirm the diagnosis of asthma. For someone with asthma, this chart indicates poor control and more treatment is required.



This chart shows readings that are dropping from day to day. This person has poorly controlled, deteriorating asthma. Urgent help is required.


This peak flow chart shows a gradual improvement in readings. This is normally seen after someone has started asthma treatment.

April 11, 2012 at 9:21 am | Graph | 31 comments

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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August 27, 2012 at 10:01 pm | Networking | No comment

Removing Asthma Triggers from Hallways


It is important to reduce the number of Asthma triggers in the entrance to your house, as many triggers from the outside may be brought inside. Here are a few ideas of how to remove triggers from entrance and hallways.

Use a doormat as this can collect allergens and stop them entering the house. The doormat should made from synthetic materials as doormats made from natural materials may break down.

Light Fittings
Remove any dead insects from around your light fittings. As the bodies decompose they can become a source of allergens.

Shoe Rack
Place a shoe rack in the entrance and encourage people to remove there shoes. This will reduce the amount of dust and allergens that are brought into the home on the bottom of peoples shoes.

Hard Floor
Consider removing carpets and replacing with hard floor for easy cleaning.

Free image courtesy of FreeDigitalPhotos.net

August 26, 2012 at 11:07 pm | Life Factors | 1 comment

Removing Asthma Triggers from the Bathroom


The bathroom is often warm and wet. Which makes the bathroom the perfect place for mould and mildew to grow. Below are some ideas of how to remove Asthma triggers from the bathroom.

Shower curtain
Regularly was the shower curtain.

Bath mat
Regularly wash the bath mat, as a damp mat can attract dust mites and mould growth.

Extractor fan
Switch on extractor fan or open window after having a bath or shower, to remove damp from the bathroom.

Check under the basin for leaks.

Toilet Overflow
Check that the toilet overflow has been fitted correctly and works. To prevent water from leaking into the walls.

Bathroom Tiles
Regularly check the grout around the titles to prevent leaks that could lead to mould growth.

Free image courtesy of FreeDigitalPhotos.net

August 25, 2012 at 9:11 pm | Life Factors | No comment

Removing Asthma Triggers from the Bedroom


It is very important to remove Asthma triggers from the bedroom, because of the amount of time that you spend in bed and many people find that there Asthma worsens during the early hours of the morning (sometimes called the Morning Dip).

Below are a list of ideas for removing triggers from the bed room

Ensure that pillows have synthetic fillings. Consider covering the pillows and mattresses with dust bite barriers.

Hard Floor
Wherever possible replace carpets with hard flooring and rugs that can be easily washed.

Replace curtains with blinds that can be easily wiped clean.

Remove anything that contains natural feathers, dust mites love feathers.

Plush Toys
Consider removing soft toys like teddy bears, or wash them regularly.

Change to a metal or wooden bedstead.

Free image courtesy of FreeDigitalPhotos.net

August 24, 2012 at 9:12 pm | Life Factors | No comment

What are Asthma Triggers


An Asthma trigger is something that makes your asthma worse. Generally Asthma triggers do not cause asthma, but they bring on Asthma symptoms or attack. There are many different Asthma triggers, here are a few of the common triggers:

  • Health triggers (Example : Common cold, flu)
  • Environmental triggers (Examples : smoking, traffic fumes)
  • Occupational triggers (Examples : flour, solder, latex)
  • Emotional triggers (Examples : stress, laughter excitement)
  • Allergic triggers (Examples : animals, house dust mite, pollen)
  • Body triggers (Examples : Menstrual cycle, pregnancy)


Free image courtesy of FreeDigitalPhotos.net

August 23, 2012 at 7:37 pm | Life Factors | No comment

Download Peak Flow Chart


You can save your peak flow chart as a image file (png) simply by clicking the save icon. The icon looks like a computer disk and is situated below the graph. After clicking save a dialog box will open asking you if you wish to save the image or open. Open will open the image on your local computer. Save will save the image to your downloads folder.

Save Icon

Save Dialog

May 4, 2012 at 12:22 am | Graph | 17 comments

Recording Medication Changes


Changes in you medication can have a dramatic effect on your peak flow readings. The Peak Flow Diary website allows you to record any changes in medication. To do this go to the Chart page and then click the Medication Record icon, which is situated below the graph.

Medication Icon

Enter the date of the medication change, then the medication name, dose and finally the frequency the medication is taken. Then click record.

Record Medication Change

The medication change is then display on the graph as a blue circle. Clicking the blue circle will display the information about then medication change.

Display Medication Change

May 4, 2012 at 12:01 am | Medication | No comment

Recording Life Factors that affect Asthma


The activities you do and the objects that you come into contact with every day can have an affect on your Asthma. For example going to the gym, walking the dog, doing DIY, etc. On the Peak Flow Diary website we call these events life factors.

Using the Peak Flow Diary website you can record these Life Factors to help explain any changes in you Peak Flow Readings.

On the Chart page click the Life Factors Icon which is situated below the graph. The icon looks like a flag.

Life Factors Icon

Then enter the date of the event and then enter a description of the event in the the text box. When finished click the Record button to save the Life Factor.

Recording Life Factors

The life factor is then displayed on the graph as a red circle. Clicking on the red circle will display the description of the life factor.

Displaying Life Factors

May 3, 2012 at 11:39 pm | Life Factors | No comment

Print Peak Flow Chart


Using the peak flow diary web site it is easy to print your peak flow chart.

Sometimes it is necessary to print your peak flow chart. For example when you go to see your doctor or asthma nurse, you may was to take a paper copy.

print peak flow chart

Simply use the start and end dates to select the period you wish to view, then clickthe graph button. This will update the graph, to show the selected period. Then from the icons below the graph click the print icon. The graph will then open in a new tab. Now use the print command within the browser to print the page. Normally the short cut keys to print is control + p.

Print Icon

May 3, 2012 at 11:15 pm | Graph | 12 comments

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This Web site is not a substitute for professional medical advice. Materials available through this Web site are for informational purposes only. You should contact your physician if you have any questions about your medical condition, or if you need medical help. If you need emergency medical help, you should immediately call 999 or your physician.