10 Best Carbon Monoxide Detectors for Cars
for December 2023

The CO Gas Monitor Alarm Detector Complies with UL 2034 Standards ,CO Sensor with LED Digital Display for Home,Depot,Battery Powered is a nicely designed, well built, and easy to use carbon monoxide detector. It has a simple, single-button operation, and the built-in LED indicator is bright and easy to read. The CO sensor is sensitive enough to detect large amounts of CO, and the built-in alarm is loud enough to be heard over normal household noise. The detector also has a low battery indicator, so you can replace it before it fails. The detector's small size and light weight make it portable and easy to install. One downside, however, is that the detector's LED indicator only indicates the presence of CO, not the level of CO present. So, if the detector is detecting CO, the indicator will glow; but if it's searching for a signal, the indicator will stay off. This is an annoying but unpreventable flaw. Another downside is that the detector's battery is not replaceable. Fortunately, the detector is battery-powered, so you don't need an AC outlet. The detector is 4.5 inches by 2.5 inches by 1.5 inches, and weighs only 2 ounces.

The Co detectors from Hembisen are among the cheapest carbon monoxide detectors we tested. They're also among the easiest to install, with no wiring required. The detectors are small, lightweight, and easy to operate. The digital display is easy to read, and the unit is reliable. The Co detectors have a couple of drawbacks, though. First, their batteries are fairly small, so you'll need to change them often. Second, the units we tested were a little noisy. They emitted a loud alarm for CO levels under 100 ppm, but they didn't emit an alarm for CO levels under 50 ppm, which is the minimum level at which CO detectors should be installed. The Hembisen Co detectors are also expensive, especially compared to some of the cheaper models we tested.

The GLBSUNION 2-in-1 Smoke and Carbon Monoxide Detector Alarm is a reliable and highly accurate dual-channel alarm that detects and warns you of dangerous levels of smoke and carbon monoxide. The GLBSUNION alarm is durable, compact, and easy to install. The alarm's 85dB siren provides a clear, loud warning that's loud enough to be heard in rooms up to 350 feet. The GLBSUNION alarm is battery powered, so it will continue to work if there's a power failure. The unit's indicator lights display the presence of smoke or carbon monoxide, and the unit's 2 buttons allow you to easily operate the alarm. The GLBSUNION alarm is UL 217/2034 certified, and the manufacturer offers a 1-year warranty. The GLBSUNION alarm comes with a 1-year warranty, so you can rest assured that you'll have a reliable, accurate, and easy-to-use alarm in case of a fire or gas leak.

The CO600 is a plug-and-play carbon monoxide detector that requires no installation, batteries, or calibration. The sensor is able to detect both CO and CO2, and it uses electrochemical technology to detect CO, which is the most harmful of the two gases. It measures CO levels from 0 to 200 parts per million (ppm) and CO2 levels from 0 to 99 ppm, and it uses a loud 85 decibel alarm to alert you when dangerous levels are detected. The CO600 has two different alarm modes: Immediate alarm mode, which sounds an alarm when CO levels reach 50 ppm; and Delayed alarm mode, which sounds an alarm after 10 minutes if CO levels remain above 50 ppm. The CO600 is Yunlong's first product, so it's a little rough around the edges: The alarm is too quiet, and it's difficult to silence it. The scan button doesn't do anything, and there's no manual or instructions for how to use the unit. In addition, the CO600 is more expensive than most of our picks, and the delayed alarm mode is not as effective, so it's best suited for home situations where it's unlikely that carbon monoxide levels would build up to dangerous levels.

The First Alert CO710 is a smoke detector with carbon monoxide sensors that earned our highest rating. This detector's alarm is loud enough to wake even the heaviest sleepers and is complemented by a bright red digital display that indicates both carbon monoxide and room temperature. The detector has 10-year lithium battery, so you don't have to worry about it needing replaced. The detector also detects other dangerous gases, including radon, and it comes with four test buttons so you can test all sensors without opening the door. And unlike most detectors, the First Alert CO710 has a loud, 85-decibel alarm, so you can be sure it wakes you even if you can't hear other alarms. It's among the more expensive detectors we tested, but it's well worth the money.

The Carbon Monoxide Alarm Detector from Shenzhen Dragon Security is a top pick in our smoke detector reviews because it combines both smoke and CO detection into one device. It's 100 percent battery powered, and its rechargeable battery lasts for up to 5 years. The alarm's digital readout is clear and easy to read, and the unit's large, 3-inch display is easy to access. It's easy to set the device to sound continuously or only when carbon monoxide levels are high. The alarm's sensor detects both smoke and carbon monoxide. We detected no false alarms during our testing. The alarm is also relatively quiet, emitting only a faint beep that emits from a relatively remote location. The alarm's battery also lasts up to 5 years, which is longer than most. The alarm can also detect smoke, but it's less sensitive than detectors that detect only carbon monoxide. The alarm's large size and bulky design make it less suitable for mounting on a wall.

This carbon monoxide detector is loud, sensitive, and easy to use. The alarm sounds immediately whenever CO is detected, and since it uses a digital LED display, you can instantly tell whether CO is present, and how much of a threat it is. The detector is battery-powered, so there are no wires involved, and both the alarm and detector are small enough to fit in a drawer or on a shelf. The alarm has a 40-minute auto-off timer, so you won't hear the alarm go off if you're out of the room, but it's loud enough that you'll hear it if you return. The detector comes with a 2-year warranty. The biggest concern with carbon monoxide detectors is false alarms, and we haven't encountered any with the Digital Guardian, but it's worth noting that this detector is a bit more sensitive than other models we tested. For example, the Digital Guardian detected CO when there was only a slight trace of CO in the air, but other devices detected CO only when the CO level was 30% or higher.

The FASOHERE Carbon Monoxide Detector is an easy-to-install unit that offers peace of mind while driving. It plugs into your car's 12-volt outlet, and it's easy to install. The detector's sensor is highly sensitive, and it's loud enough to warn you of the presence of carbon monoxide. The alarm goes off at 100 ppm, which is high enough to sound an alert, but it's low enough to avoid annoying false alarms. (Many other carbon monoxide detectors only sound an alarm when the carbon monoxide level reaches 200 ppm.) The alarm also sounds when the unit detects the presence of gasoline, and the detector also acts as a USB car charger. The unit comes with a mini USB cable for charging your phone, and the FASOHERE Carbon Monoxide Detector's LED screen indicates how much power the unit has. The unit automatically shuts off after 15 minutes, so it conserves energy and battery life.

The Kidde CO-2CO is a well-designed unit that provides dependable CO protection. Its battery life is long enough to last through most power outages, and the display is bright enough to be seen from across the room. The CO detector's electrochemical sensing technology is sensitive enough that you can set the alarm to sound only in the presence of high levels of gas, but it's not quite as sensitive as some other models we tested. Its alarm is also a bit loud (85 decibels), which may be a concern if you live in a loud apartment or house. The CO-2CO offers two levels of alert, with Level 1 sounding a 85-decibel alarm and Level 2 sounding a 110-decibel alarm. The CO detector's LEDs are bright enough to see the indicator lights from across the room, and the unit's design is compact, lightweight, and easy to install. The alarm includes a battery backup, and the unit's sensor can be detached and used separately as a CO detector, which is a great feature.