As part of my blog article about carbon monoxide detectors, I decided to test a couple out.
To that end, I purchased a Kidde KN-COPP-B-LPM. This is a small battery powered device, exactly the type that would be great for an overnight trip. It displays CO in PPM on an LCD, and is a UL2034 listed sensor. Cost was $19.37.
I also picked up a Floureon battery powered unit. The Floureon is sold under various names on Amazon. It’s made in China, and is not listed with any safety spec. The Floureon also displays CO in PPM via an on-board LCD. Cost was $9.99.
Kidde Carbon Monoxide Alarm KN-COPP-B-LPM
Battery-Operated Carbon Monoxide Alarm with Digital Display
My tests showed that both sensors worked well to detect a relatively high concentration of carbon monoxide. However, which one would I put on my wall? I personally would go with the Kidde. It costs a bit more, but I at least know that the design has been tested by a third party (Underwriters Laboratories).
This wouldn't be a complete test without tearing down the sensors. Both devices run on 3 AA size batteries. Both are also a great study in cost reduction. Neither sensor uses screws - they simply clip together.
First the Floureon sensor:
Next the Kidde top:
It was interesting to see how much larger the Kidde electrochemcial cell was compared to the cell in the Floureon device. Bigger doesn't necessarily mean better, but I did see that the Kidde sensor was serialized, with data printed right on the can. That suggests each cell is individually tested.
Overall, the Kidde seemed to be better assembled in terms of quality.
I wasn't able to read the part numbers on either device. The Kidde sensor was embedded in wax, while the Floureon had part numbers sanded off.
So why did the Floureon sensor go into alarm so much sooner than the Kidde? It all comes down to the UL 2032 code for CO detectors. The Kidde sensor is UL listed, which means it was tested (at great expense I bet) by Underwriters Labs to comply with the standard. A good portion of the 2032 standard is about reducing false alarms. My best guess is that the Kidde sensor has software running which will wait a certain amount of time before triggering the alarm.
The Floureon sensor on the other hand isn't listed with any safety agency. They were free to use any false alarm delay they wanted.
I'll be the first to admit that this is not a scientific test. However, it is a practical test that anyone can do at home. First a bit of safety - do this test outside, and be careful to not inhale any of the CO check gas.
I set things up on my patio table. The two CO alarms fit nicely into a 1 gallon Ziploc bag. I pushed out as much as air as I could from the bag, then zipped it down on the tube which comes with the CO check can. I started a stopwatch and injected the gas.
The Floureon sensor took just 17 seconds to start beeping. A CO alert is 3 beeps followed by 5 seconds of silence, then the pattern repeats. The Floureon sensor was already reading 830ppm. At 33 seconds, the Floureon sensor read 970 PPM while the Kidde sensor read 0 PPM.
At 51 seconds, the Kidde sensor displayed 415 PPM, but it didn't go into alarm.
The PPM displayed on the Kidde sensor continued to rise.
At 2 minutes 13 seconds, the Kidde sensor went into alarm.
The final display was 811 on the Kidde, and 970 on the Floureon.