CO2 Detector, Dienmern Carbon Dioxide Monitor Meter With NDIR Sensor, 6-in-1 Air Quality CO2 Monitor With PM2.5/1/10, Temperature & Humidity Real-time Reading, CO2 Alarm Meter(on/off)

It’s very easy to use, it really identified to me how much rebreathed air I have in my house! I’m much more conscious of opening windows now. I thought I was good before. The levels of CO2 build up really quickly, we end up switching it off in the evening, on a cold evening with just the family you’re not going to open the windows to reduce the levels but with guests you really should at this time so I’d leave it on if we had guests in the house for everyone’s sake.

With the talk about indoor air quality in the context of Covid and carbon dioxide levels being a proxy for quality of ventilation, getting a monitor seemed a good idea. I chose this one as being more pricey than some others on offer while being much cheaper than more industrial options. It is sturdy, with a bright illuminated display and I can confirm that its battery gives well over 8 hours from fully charged; I've not tried letting it run down completely. For full-time monitoring it will need to be plugged in, which is what I've done. Taken out of doors before switching on, as advised, it settles to a CO2 reading of 413ppm every time. Bringing it back indoors and placing it in the living room, the reading rises considerably. It is interesting to see the level rise through the day when we are moving around indoors and further when the gas hob in the kitchen is in use (even with the cooker hood in operation). A few times it has risen to the 1000ppm level that triggers the alarm (a warning though still well below the truly dangerous level). Breathing out directly at it causes the CO2 reading to rise sharply.The temperature indication is well in line with several comparator devices of different brands but the relative humidity reading is typically about 5% lower.I can't vouch for its CO2 accuracy, though it certainly responds consistently to changing conditions. Nor can I say if this device is more accurate than the cheaper ones on offer. It is sturdy and nicely presented.

Three different sizes of particulate pollution, very useful info.. the only criticism is the Co2 alarm can be irritating but hey, I’m splitting hairs when it is doing it’s job. I’m happy with my purchase & it could make a big difference in habits, health & safety.

This monitor seems to do it's job. It certainly displays CO2 levels, temperature and humidity, to the nearest whole unit. It seems to take a while to find a CO2 reading after first being turned on, so I assume it is doing some averaging over time.Annoyances are the battery level indicator seems to flicker between green and red while plugging into USB, as though it can't decide if it is fully charged or not. Distracting from the corner of the eye when on a work desk. Another annoyance is the CO2 level alarm, that sounds a bleep whenever the levels are rising and over 1000ppm. This can be turned off by double clicking the one control button it has, but it does not remember this setting, so you have to remember to do this every time you turn it on, and since there is no way of telling if the alarm is on or off, you have to wait until levels are over 1000ppm to see if it sounds or not. Poor design, in my opinion.If I were buying again I would probably spend a bit more and try to find a better one.

Unit was nice and compact and easy the read. Problem was it could not hold a charge for more than a few minutes (green to red) so I plugged it in using a usb. This worked for an hour or so but then it shut of again, tried a differ usb and it would switch on for a few seconds then switch off. Which is a shame as I liked it's looks and display.

Other than occasion need to reset the unit, it's been working perfectly for a few months now.I bought it to monitor PPM levels when using a log burner, and it's very responsive to any slight change in the environment.

It works very well for me as a guide as when we need to either increase ventilation, scrub the air in the room or decrease the number of people in the room.

You need to keep in on charge as it doesn’t last vey long, it’s not the same as a carbon monoxide monitor. The light is so bright so I can’t sleep, the alarm kept going off as soon as I shut my curtains so I have to leave a window open just so the alarm goes off and keep it open alright which isn’t safe, so I’m returning it.