EGAir Quality Monitor, Formaldehyde Detector, Pollution Meter, Sensor, Tester; Detect & Test Indoor Pollution, TVOC Volatile Organic Compound Gas, PM2.5 2.5 Micron Particulate Matter Dust; eBook

The media could not be loaded. I purchased this product to test the air quality of the manufacturing shop I work in. OSHA was on site recently and during my conversation with the OSHA inspector it came to my attention that my company had not disclosed to OSHA that we weld Chrome Rod. I also learned during this discussion with OSHA that welding Chrome Rod is toxic and a known carcinogen. We all knew that the air was incredibly unhealthy as it regularly looks like a rock concert with fog machines in the shop, but finding out that it wasn't just regular weld smoke but potentially toxic Hexavalent Chromium that we were breathing in all day motivated me to purchase this device to monitor the air quality myself. I am very happy with how this performs, directions are clear and concise which made it easy to use as I have no experience operating this equipment before. When I start it up outside it shows the Particulate Matter of our outdoor air as a reference point, usually around PM 2.5 12 or so, a safe "Good" level. Then after it has adjusted to the outdoor air and I walk through our shop the sensitivity of the device shows and it instantly starts climbing from "Good" to quickly passing "Moderate" and rising to "Unhealthy for Sensitive Groups" then to "Unhealthy" charging on to "Very Unhealthy" then finally reaching the "Hazardous" designation before it finally maxes out the meter at a PM 2.5 of 999. I find the design very useful as it references different levels as mentioned this way, although I hope you don't find yourself in the "Hazardous" level like we usually are in our shop. I chose the beginning of this video to demonstrate what it looks like going from fresh air outdoor to our poor air inside, I had to trim the video due to its length but also included a picture of the meter while it is maxed out at PM 2.5 999.

** Update 12/8 ** I've updated from 2 stars to 4I had to post an update because of the amazing customer service.. it wasn't immediate but it was efficient. I honestly didn't expect much at all and was planning on returning my device. I did not and here's why..I purchased during the CA wildfires so I could not calibrate the device and it was inaccurate. So, if you are buying during bad air quality outdoors it will not be accurate, though will still show you if things get better or worse until you can.Once I calibrated to the "fresh" outdoors a couple weeks later when our "hazardous" (worst in the world) air became "fresh" I could spend more time working on calibrations.. it took several attempts and did this over several days (2 weeks) in an effort for consistency. I did have to adjust manually but the online eBook was helpful through the process.I'm not sure I totally believe all of the HCHO are totally accurate as I know some essential oils that actually aid in respiratory health and if nearby will set the monitor off, then dissipate over 10-30 min and the machine is happy again. So, some things heavier than air will register.. know what is nearby and make your own conclusion as to your safety of the air.The PM2.5 which is huge for CA wildfires and to me, with a respiratory medical disability is most important. It is quite accurate though once you finally calibrate. Because of the time it took me to calibrate and believe the unit, I didn't want to return the unit. What I found out was that it's difficult to find machines that will show US guidelines so you will get a green, yellow, or red face on your machine. Just know, it is still green when it should be yellow/orange in US guidelines. I was willing to keep the unit for a discount for all of these difficulties and the company came through and compensated me more for my troubles.I've upped my rating from 2 to 4. My reason for not a full 5 is because of the time to actually get things working as they should and the fact I basically have the US standards memorized, I can't always count on the happy green smile to be good for my own health. The readings however, are pretty much dead on now (outside) with EPA reports. I do believe your results will be accurate, however you may need to decipher them to US standards or your own personal sensitivities. The company is very receptive to questions and offering a response.---------------------------------------------------ORIGINAL POSTI purchased this during the CA wildfires when the air quality was in the "Purple/Hazardous" zone on the US charts (see my last photo for US PM2.5 values). Our air quality PM2.5 was over 300 ug/m3 but this tester showed a yellow "poor" face. Since you can't calibrate it indoors, I had to wait 12 days to get a good air quality day. I've recalibrated the machine at least 5 times. The time apparently resets each time you do this too so the time is always back in 2015.I give the unit 2 stars because after calibrating is is moderately accurate. Not enough to use to measure actual air quality standards, but it will fluctuate when put near harmful products enough to know there are VOCs around. The fact it tests for formaldehyde is cool too, but I'm not sure about the accuracy as it jumps from green to poor and back for no apparent reason.Photos in order:The first photo is show what my unit looks like purchased at $109. I clicked in the link to review earlier today and this model ( https://www.amazon.com/dp/B074FTVHFN/ref=dp_prsubs_1) showed up with all the same reviews and comments as the model I have. Hmm As I review this afternoon, the image again shows my model purchased. Just be aware what you are purchasing.Second photo is after all of my calibrations on another day the PM2.5 was reported by the EPA here as 57 which is unhealthy. The unit read 54, not too bad. The PM10 was off considerably. The biggest issue I have is that after reading the manual, I finally realized why the unit kept saying "normal" when it was "unhealthy" by US standards. The unit goes off the China air quality chart (see photo 4 from manual). Photos 3 and 4 show air quality taken at the same time as the monitor indicated in photo 2. For this reason, the unit is not useful to me as someone with respiratory issues that needs the US air quality results. See last photo 6 for US standards chart and compare to what you will actually see with the unit on photo 5 China standards chart.It's just too far off for me and I'm not going to figure it out on my own, though one could. I contacted the seller 3 days ago as their email said to do that before posting a negative review but have heard nothing back. My request was asking how to change the unit to US standards if it's possible at all. If that can't be done, I will be returning it. I'm hoping this review will prompt a response, otherwise the unit is going back.