How are peak flows taken, and in particular how do I do this as a blind person? I am posting this here in a public post in answer to a question from my friend shazza59 but also because others may be curious about it.
There is a device called a peak flow meter which has a piece that moves when blown into. There are different types of meters, but the idea is similar to a thermometer. My device has markings up the left side in increments of 10. I'm not sure where they start or how far they go. It has two movable pieces on that side which can be used to mark significant places. I have mine set at 250 and 450. So I can estimate the measure by figuring out the distance from one or the other. It is not a completely accurate method, but I am usually within 10 points (or whatever you call this.)
I have had an asthma diagnosis since 1995 and have been doing peak flow measures since 1999. I've gotten to the point that I can guess my approximate peak flow without measuring and just use the meter to confirm. I function on most days between 400 and 450. During my illnesses, I can get down in the 200 to 250 range. Generally my measure goes up after a nebulizer treatment with Xopenex. The reason I've been so concerned lately is that I had been staying at 250-300 even after the treatments.
I don't know of any accessible peak flow meters, primarily because of the way they are made: with the piece that physically moves and the numbers in such tiny increments that they can't be marked tactually. If there was such a thing as an electronic meter that worked like a digital thermometer, it could be made to talk. I wish such a thing existed!