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Peak flow measurement

Visitors to take a peak flow test to measure how fast they can blow air out of their lungs.

To introduce the concept that we can measure lung function and that this can deteriorate for people with allergic asthma.

How to make:

  • You will need at least two peak flow meters - preferably one 'adult' size and one 'child' size - as well as disposable cardboard mouthpieces.
  • Draw a graph of height vs. peak expiratory flow (PEF) on some A1 or A2 flipchart paper and attach to an easel or something similar.
  • Ensure you have a tape measure handy or a metre stick to measure people's heights.

What to do:

Ask visitors to take a peak flow measurement and plot it against their height. To take a peak flow reading, check the monitor is at zero and the visitor is sitting/standing in a comfortable position. Place a disposable mouthpiece over the peak flow meter mouthpiece and, holding the meter horizontally, they should take a deep breath and close their mouth firmly around the mouthpiece. They should then blow out as hard as they can (like blowing out candles on a birthday cake). Next, ask them their height or, if they don't know it, measure them with the tape measure. Ask them to plot their height against their peak flow reading - for small children you can do this for them if you need to. Over time you should see a correlation between PEF and height (i.e. taller people generally have bigger lung capacity as detailed by their PEF). Use this to explain what other factors can impact on PEF - such as allergic asthma.