The Best Carbon Monoxide Detector 2025
To put these detectors to the test, we went into the lab and built a test bench designed to measure the response time of each device at various concentrations of carbon monoxide, specifically at 250 ppm and 400 ppm. Our goal was to determine the respective performance of each detector in detecting potentially dangerous levels of carbon monoxide. To announce our winners, we also considered features that add to the overall user experience, performance and profitability of each unit.
For the 250 ppm concentration level, we are trying to simulate a situation where carbon monoxide has started to build up to dangerous levels. We test twice at this concentration and average the results. At 400 ppm we reproduce the worst case scenario, a potentially lethal situation, and give the modules a pass or fail score. Spoiler alert: All of these will save your life, which shows the importance of having carbon monoxide detectors installed on every floor of your home.
Our custom built carbon monoxide detector test station. It’s one of the deadliest things we’ve created in our product testing lab.
This is one of the most dangerous tests we have ever conducted. Carbon monoxide exposure is no joke. It’s virtually undetectable and, well, quite deadly. We needed to create a safe way to test carbon monoxide detectors without risking the health and safety of our lab staff. So I used my rudimentary carpentry skills and built a carbon monoxide detector test station. Its components are:
Carbon monoxide detector chamber: Made of wood, plexiglass, silicone, duct tape and a bunch of nails.
Carbon monoxide tank with gas flow regulator: Cylindrical tank containing carbon monoxide at 2500 ppm and balanced air.
Testo 300 with carbon monoxide Ambient sensor: Our control device for this experiment.
Two portable carbon monoxide gas alarms.
A look inside CNET’s carbon monoxide detector test rig.
The chamber houses two carbon monoxide detectors, a) the ambient CO sensor part of our control device, the Testo 300, which is a combustion analyzer used by heating engineers who carry out the installation and routine maintenance of industrial and residential heating systems, and b) the unit under test, or UUT, which takes the place of any carbon monoxide detector we have tested for you. The chamber is sealed with foam but not airtight as we are not particularly interested in making a carbon monoxide bomb.
We use a portable carbon monoxide alarm on the gas regulator to protect the nose from leaks.
We installed a gas flow regulator on our tank to avoid pressure spikes, followed by a gas line to feed our gas mixture into the chamber. Two additional portable carbon monoxide detectors are used. One near the valve to ensure there are no leaks and another to be worn by the person doing the experiment to ensure there is no build up of carbon monoxide in the area of ​​the test station. On top of that, our respirator suits and well-ventilated area ensure that we get a constant flow of fresh air at all times. All of this may sound excessive, but it’s always good lab practice to put safety first, especially when dealing with such a stealthy and prolific killer.
We start by feeding our gas mixture to the chamber and carefully monitoring the carbon monoxide concentration in the Testo. Once the concentration in our chamber reaches at least 250 ppm or 400 ppm, we stop the gas supply and start a timer. We want to estimate how long it takes carbon monoxide detectors to respond to these conditions. As you may understand, we wanted to limit our exposure while ensuring our results were reproducible.
Our results are summarized in the interactive graphic below:
English