ozone test strips work well; It's actually a plastic stick with Shenbein paper on top. It's important to note that you must read the strips in micrograms per cubic meter, not milligrams; it's a huge difference. If you are trying to convert values to parts per million (PPM), you need to know a few other variables such as temperature, barometric pressure, molecular weight (molecular weight of ozone is 48 g/mol) and the total value in micrograms per cubic meter (which you can find from the color of the strip after sampling). You can compare exposure levels with PEL OSHA and AIHA.
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