Portable CO2 Meter Handheld CO2 Detector Monitor 0~9999ppm, Carbon Dioxide Meter with Alarm Function, Temperature & Humidity Meter NDIR Sensor Air Quality Monitor for Home Trip Classroom and Office

Portable CO2 Meter Handheld CO2 Detector Monitor 0~9999ppm Product arrived quickly and was brand new. I put in the 4 batteries and hit the top left start button, and it fired right up. This CO2 detector is a game changer. I thought the office had a Carbon Monoxide problem. After buying a expensive CO detector [everyone should have a CO detector of some type] I found out with this device it was CO2 that was the problem. The room was running at 800 ppm to 900 ppm and thats when a absolute brain fog would hit. We ended opening up some windows limiting the use of the gas stove and brought in fans for circulation. The PPM is now about 500 ppm sometimes around 430 ppm which is a huge difference. I have not messed with any of the setting so far no need to. Overall excellent product! If you are having a brain fog or feel a little strange and lethargic in the house/room or office it may be high CO2 levels. This device will help determine if that is the issue, and hopefully help you solve it.

We've bought several of these over the years and they are workhorses. Alway work, battery lasts forever, accurate and consistent.

Used to measure CO2 ppm in a space heated by kerosene. The meter instructions says it is factory calibrated at 400 ppm. It read 432 in the outside air. I don't understand people's issues with the manual. It is easy to read. The calibration instructions are clear but yes you do need the manual. I have not check the accuracy with test gas as those test cylinders are ~ $200. Regarding the calibration procedure and for the fear of losing the manual. Take a picture of that paragraph and put it in the case. Potential problem addressed.

Indispensable instrument in this time of pandemic to ensure that your environment is adequately ventilated. I’m glad I bought this; my tightly sealed house had a reading of 1600 PPM CO2 and this meter clearly shows when the windows have been opened long enough to bring CO2 down to a healthier level of 600 to 800 ppm. Buy this if you want to look like a contractor. It’s ginormous and yelliw but actually light weight, especially for the size. C02 reading comes up in 30 seconds after a countdown; initial indoor relative humidity indoors after unit is outdoors takes a while to stabilize maybe ten or 15 minutes. The toggle between air, wet bulb, and dew point temperature is nice; kind of wish it also showed heat index. Now the bad: Terrible human factors design; without the manual you’d never figure this thing out - fortunately the tiny manual explains it all pretty well. Don’t lose the manual. Buttons are excessively debounced to the point that sometimes a button press isn’t recognized. A RS232 interface??? Stone age technology and forget about using your phone to log data. Alarm initially set to 1000 PPM probably isn’t a good choice; if you take this to your local grocery store or neighborhood bar or school or workplace and make a measurement that’s above this strict limit you’ll freak everyone out. It’s easily changed (but don’t forget the manual) I would buy this again. It works well. I like it.

If you want to know whether your are living/working in fresh or stale air, this is the perfect tool. It is not a cheap purchase, but quality is rarely cheap. I love mine and wish more people were cognizant of air quality (which makes a difference during cold/flu/air-borne pandemic season). Great item.

Works as described

Bought "used like new." No operation manual included.

Scary but educational - may make you open windows !!!!!