Macherey-Nagel, 90736, Ozone Test Sticks, Box of 12 Strips. Determination of Ozone in air.

The ozone test strips work well; it's actually a plastic stick with Schoenbein paper on the tip. It's important to note that you need to read the strips in micrograms per meter cubed, not milligrams; that's a huge difference. If you're trying to convert the values to parts per million (PPM) you need to know a few other variables such as the temperature, atmospheric pressure, molecular weight (ozone has a molecular weight of 48 g/mol), and a general value of micrograms per cubic meter (which you determine based on the color of the strip post sampling). You can compare to the OSHA and AIHA PELs for your exposure level.

Used this to make sure my UV light sterilizer wasn’t emitting harmful levels of ozone. The test seems to work well; there is a slight color directly next to the sterilizer but no color about 3 meters away. Easy to use, results appear in 10 minutes. Would recommend having these on hand for safety if you use UV lights very frequently.

These test strips are low budget items and I did not expect much in the way of accuracy. The"test " procedure is very basic. You simply remove a strip from the container; let it sit in the open air for 10 minutes and then match the color on the strip's tip to one of those on the container which go colorwise from clear to dark to supposedly indicate ozone level. Living in LA for 23 years and breathing this stuff I realize it is too late at this stage of my life to expect the information gained to do me much good healthwise. I did notice that when I left the strip out for about eight hours (they claim that is not accurate) the strip indicated the heaviest ozone level. The ten minute measurement came out normal with no indication of ozone. If you can figure this out good luck. I think someone has come up with a way to make $20+ quickly and I fell for it. If you just breathe ozone for ten minutes each day you will be ok. Unfortunately I have been breathing it for 24/7 for a total of 41 years. .

Works great for an ozone gas leak detector. You can't put your nose up to the fitting to see if it is leaking because if you do and it is, it will RUIN your day! You certainly won't be able to smell any more ozone leaks for a while! If you place the strip next to a fitting that is leaking, it will immediately change color.

Much lower cost alternative to the very complex electronic meters that require regular recalibration. Seems to work well: I put a stick into a SoClean device that creates ozone for CPAP equipment disinfection and got deep coloration very quickly. But the lowest registering measurement level is 90 ug/m3 (about 45 ppb). Our sticks show no color approaching this low point in our bedroom even though we can smell some ozone from an air purifier. We understand that ozone can be detected by a nose at levels of about 5 ppb so we know we have at least that amount. It would be great if these test sticks could be updated to measure levels below 45 ppb.

Great product. It works just as it should be!I bought a travel size ozone machine and just wanted to make sure it really releases ozone.

Very sensitive ozone test sticks for cold plasma jets

The strip on the left was in our house for 10 min. The strip on the right was outside for 10 min. I know for a fact the ozone was 127 for our area. The strips both look to be below the 90 minimum. These strips are worthless and you should not buy these. I want a refund.