kingneedHCHO Detector Air Quality Monitor Professional Laser Dust Sensor Indoor Real Time Detector and Highly Accurate LCD Display High Capacity 2600mAh Rechargeable Battery Portable Cube Design

I bought this to see what my air quality was like indoors in Phoenix. It registered a very low 8 - 10 consistently in a centrally air conditioned home (as I would expect).I brought on a trip to Long Island, NY and tried there. As expected it measured considerably higher outside (100 give or take 30-40 points), but inside an air conditioned home the quality was much better (as hoped - well under 100). I took outside on the evening of the 4th of July and as expected the reading was much higher (between 300 and 600, depending on where the breeze took the fireworks smoke). I am not concerned about the precise number so I can't comment on it's accuracy, but the relative air quality was a concern, especially indoors. This will be used frequently in and out of the NY home to be aware of how the air quality is at any given time. As a side note, the rechargeable battery does not last long if kept powered on continually, so we turned it on briefly when we wanted to see the reading and kept it powered off at all other times to conserve the battery - not an issue.

UNIT INACCURATE; ALL MORNING READING WILL SHOW "005" PPM, ONE BLUE DOT FOR "EXCELLENT ". THEN AT THE END OF THE DAY, WHERE IT HAS NOT CHANGED VALUE ALL DAY LONG, SITTING AT 005, WHEN SHUT OFF AND PLUGGED IN TO CHARGE TO 100%, UNIT UNPLUGGED, TURNED ON, NOW SHOWS "499, 500" CLIMBING, AND BLUE DOTS NOW SHOW ALL 5 DOTS FOR "HEAVY CONTAMINATION"///UNIT IS INACCURATE, DO NOT PURCHASE, UNLESS THERE IS SOME CALIBRATION REQUIRED, NOT STATED IN USERS MANUAL. I WILL PURCHASE A DIFF. 2.5 PM DETECTOR, AND SEE HOW COMPARE. IN THE PIC, 5 MIN AGO, SAME LOCATION, 005, 1 BLUE DOT EXCELLENT////

This has been a great help here in CA in the path of Dixie Fire smoke plume.I learned my home is actually too leaky for the filtered household blower to help, no matter what filter I used! More bad air gets pulled in than gets filtered so room air filters have been essential.This also helped locate various leaks in my home. The fireplace, HVAC vents, dryer vent, and bathroom were letting enough bad air in that my filters couldn't keep up.The battery power has also been way more useful than I expected. I actually needed to be wearing an N95 mask in my car on top of recirculating the air it turned out in our conditions.The numbers didn't exactly add up with any variations of the AQI values I found nearby on purpleair.com, but the numbers were certainly good enough to make practical decisions and track if the air quality suddenly fell.Grateful for a simple tool like this during the fires.

The big, bright, daylight readable display enables me to put this anywhere. The readings line up reasonably well with the AirNow app. Having a numerical partial count is so much better than trying to gauge air quality by haze or smell.

this device helped me conyrol pollution in my break room

There's no rhythm or reason for the results this thing comes up with. I checked on it multiple times in a closed room with no ventilation or fans on and the only thing consistent about it was that it always said something different. It had quite a bit of variation even though there's literally no way the air quality could have changed. I returned it.

Reading doesn't change, so totally a waste of money.

It may have been just my device, but it was defective. The meter was jumping from around 35 to over 500 in a matter of moments in my bedroom. There were no changes in the air flow either.