Therm La Mode Air Quality Detector 5-in-1 Air Pollution monitor test PM2.5, PM10, CO2 Temperature, Humidity. Professional NDIR Sensor, Real-Time LCD Display Air Quality Monitor, CO2 Alarm Meter

PM2.5 : In the USA air quality is considered good up to a particle 2.5 concentration of 35 micrograms per cubic meter, in China this limit is 75. With this meter you also get a level of PM10 but this is calculated from PM2.5.I use the AQI (air quality index) screen the most.Up to AQI 50 air quality is labeled as GOOD, between 51 and 100 as MODERATE and from 101 on as <unhealthy for sensitive groups>. One night the device measured an AQI of 150, obviously because too many people where using their wood-stove at full power.My conclusions about the AQI results :1) the AQI (thus the air quality) is always better inside the house by a factor 2 or 3. If outside AQI is not good, limit if possible outside activities (no jogging for example and don't leave the kids outside all day)2) a HEPA air filter always improves the AQI :3) when driving it is better to use the air-recirculation which also improves the AQI by 2 or 3, rather than leave the air input open. This is because the air gets recirculated through the pollen filter. However this method lets CO2 to accumulate and oxygen to be depleted so from time to time like every 15 minutes reopen the air-intake for a minute or 2.Formaldehyde and TVOC :to my relief there is no formaldehyde in my house.TVOC however also reacts to all kinds of chemicals : as a test I put the meter close to an opened bottle of disinfectant alcohol and the meter rapidly changed from <safe> to <Unsafe> in orange.All in all this device delivers very useful information

I am so disappointed with this meter.I don’t know about the PM/AQU and HCHO accuracy, but the temperature and humidity is so wrong! It constantly shows 25 C and 42% humidity in the room. I have tested with this meter the temp and humidity over a pan with boiling water and the temp & humidity did not change!!!! How can I trust this meter at all? I have paid £159 for this! Don’t buy it!

Very (over)sensitive to PM 2.5, HCHO and TVOC. Values are exagerated quite a bit - obviously not a professional tool. Consistent and follow PM2.5 curves published officially. Doesn't meter PM10! PM10 is always PM2.5 x 1.4. Both readings change at the same time. (The PM10/PM2.5 ratio should be 3,4 in my region today and it is very variable according to official data).

The design of the device is really nice: premium materials and nice packaging.The air quality readings are very precise. I see it react to things like opening the window or more people in the room.A couple of my friends also bought the device and have said they noticed that they feel more well rested and productive. I highly recommend this air quality detector!!!

This product is intuitive to use and portable. The screen is bright and clear. However, it would be vey useful if a data-logging version were to be made available