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7 Types of Carbon Monoxide Detectors (With Pictures)

Carbon Monoxide Detector

Carbon monoxide is nothing to trifle with. It’s odorless, tasteless, and you can’t see it with a naked eye. When exposed to high levels of this hazardous chemical, humans suffer severe damage to the brain and can even die. So, how do you fight this invisible killer? What’s the best remedy against it? The answer is carbon monoxide detectors. There are lots of different offers on the market.

And in this guide, we want to introduce you to the seven types of CO detectors. They each have their pros and cons, but every single system deserves your attention. So, if you’re ready to protect the house and your loved ones against carbon monoxide, let’s check out all the available options and take a pick!

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The 7 Types of Carbon Monoxide Detectors

1. Digital Read-Out Detectors


Ease of Use/Setup: Moderate/high
Price (units + installation): Low/average
Lifespan/battery life: Above average
Best used for: Monitoring CO levels

These detectors are the best option for the average homeowner on a mission to protect their loved ones from carbon monoxide exposure. They take little effort to install and set up without professional help or detailed instructions. On top of that, they’re reasonably priced and serve for a long time. Read-out detectors display real-time and recent CO levels on a screen.

First, that gives you peace of mind whenever you suspect there’s a leak or anything like that. Second, it allows keeping all the appliances in the house in check and fixing potential problems as they come. Make a habit of taking a quick peek at the display at least a couple of times throughout the day, and you should be able to keep carbon monoxide in check.

2. Battery-Charged

Ease of Use/Setup: Very high
Price (units + installation): Average
Lifespan/battery life: Very high
Best used for: Flexibility

Tired of having to constantly charge/replace the batteries? Well, if you go with a 10-year sealed battery alarm, you won’t ever have to worry about that. As you’ve probably already guessed, the battery units in these detectors last for up to a decade. And they feature LEDs that display CO levels and even the temperature in the room.

Battery-charged carbon monoxide detectors are wireless. You can place them wherever you want, be it on a shelf, tabletop, or cupboard. And you won’t have to spend a fortune on that. These devices are more than fairly priced. Do remember, though, that the higher a CO detector is mounted, the more accurate its readings will be.

3. 2-In-1 Carbon/Smoke Detector

Ease of Use/Setup: Moderate
Price (units + installation): High
Lifespan/battery life: Above average
Best used for:  Old/newly-built houses

With this full-fledged system, you’ll get simultaneous protection both from CO and smoke. So, if you just moved into a brand-new house that doesn’t have any alarm system installed yet, a set of two-in-one detectors will be a great investment. Or maybe your house is very old, and the existing systems are outdated and not particularly efficient. If that’s the case, combined detectors will also be the right choice.

It won’t be cheap, of course (almost twice as expensive as a standard carbon monoxide detector). But, the system will serve you for a long time, and, since you’ll only have to install/mount a couple of detectors in the entire house, this can be done in 2–3 hours. Operating combined alarm systems is rather simple, too, especially if you check out the included instructions.

4. AC Plug-In Devices

Ease of Use/Setup: High
Price (units + installation): Average
Lifespan/battery life: Above average
Best used for: A home with eye-level power outlets

With AC CO detectors, the installation process is a walk in the park. Just find the closest electricity outlet, plug the device in, and that’s it. You won’t have to worry about running any cables across the ceiling or the walls or checking on the batteries to make sure they’re charged up. With that said, many brands do sell AC plug-in detectors with a pack of batteries to protect the house during a power outage.

There is one big downside, however. Since most power outlets are located well below eye level, the detectors won’t be very efficient or reliable. And you won’t be able to move them around like the battery-charged devices. For this system to deliver its best performance, you’ll have to mount the AC plug-in detectors very close to the ceiling. So, check whether you have outlets that high before making a purchase.

5. Hardwired Units

Ease of Use/Setup: Very low
Price (units + installation): Very high
Lifespan/battery life: Very high
Best used for: High-risk facilities

The term “hardwired” means you’ll have to connect these detectors to the building’s power supply; otherwise, they won’t work. Only a licensed electrician will be able to install a system like that. So, expect them to charge extra for the service. The actual detectors also come at a steep price. The good news is—hardwired detectors always come packed with batteries for backup.

That makes hardwired carbon monoxide detection systems a reasonable choice for high-risk buildings. Digital displays/read-out systems can also be a part of the deal. Hardwired detectors are often installed in thermal power stations, heating stations, and facilities that work with coal. They are the safest CO detection system available.

6. Interconnected Systems

Ease of Use/Setup:  Low/moderate
Price (units + installation): Average/high
Lifespan/battery life: High
Best used for: Office buildings

Do you already have a smoke detection system up and running? Or maybe your office is equipped with an anti-theft alarm system? If the answer is yes to any of those questions, an interconnected carbon monoxide detector might be your best option. So what makes it so special? An interconnected CO detector can get in sync with all the other monitoring/alarm systems through cables or even wireless.

That makes it a go-to choice for offices as it’s capable of relaying alarms from one end of the building to the other. Does that mean interconnected detectors aren’t the right pick for a house? In many ways, yes, that’s true. They’re not very cheap and take time to install. But, these systems do have an impressive lifespan.

7. Portable Detectors

Ease of Use/Setup: High
Price (units + installation): Very high
Lifespan/battery life: Average/high
Best used for:  Official inspections

As the name suggests, portable detectors don’t have to stay in one spot to be able to reveal abnormal levels of carbon monoxide. Small, lightweight, and hand-held, they can be easily transported in an average-sized bag. These detectors are very easy to use, too. The battery charge is quite impressive as well, and most portable CO alarm systems have an extended lifespan.

On the downside, you’ll have to pay top dollar for a single portable detector. You won’t find such a device in most US households or facilities. Instead, they’re largely used by safety inspection agencies and services that check commercial and government sites. If you’re just looking for a decent-quality detector to protect your home, this won’t be the best pick.

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Sensors: How Do You Choose the Right One?

Essentially, there are three types of carbon monoxide detectors out there: hardwired, plugged-in, and battery-powered. And then we’ve got portable, interconnected, combined, and read-out units. On top of that, you have a choice between four sensors. Here they are:

  • Biomimetic. Features gel-coated discs that get darker depending on how much carbon monoxide is in the air. The concept behind biomimetic detectors resembles how hemoglobin behaves when exposed to CO. The second the color changes, you’ll hear the alarm. These systems can work with batteries and come at an affordable price.
  • Opto-chemical. The same method applies here as well: Opto-chemical detectors include a chemical that changes its color when exposed to CO. This is the least expensive option out there. However, it’s also not very precise, especially when it has to deal with low levels of carbon monoxide.
  • Electrochemical. Somewhat similar to the previous detectors, electrochemical units rely on a chemical reaction with CO to generate electricity, which, in turn, sounds the alarm. This is the most accurate detection technology on the market. Plus, it comes with a digital display and a built-in memory feature.
  • Metal Oxide​/Semiconductor. This is the oldest yet longest-serving CO detecting system. Utilizing heated tin oxide, it’s quite efficient at detecting minor spikes of carbon monoxide in the atmosphere.

The Feature Set: Finding the Best Fit

Every single alarm system on the market comes with a set of different features. Here’s a quick glimpse at the most important ones to look for in a CO detector:

  • Official UL certification. This acronym stands for Underwriters Laboratories, a safety certificate from a world-renowned, non-profit testing lab of the same name. If you see their tag on a detector/alarm system, that means it was thoroughly tested and no flaws were detected. In Canada, you’ll most likely see a different stamp: CAS (Canadian Approval Services).
  • Digital display. Monitors and shows current CO levels in the room. And when the alarm goes off, you’ll see exactly how much carbon monoxide is in the air.
  • Memory (peak level). Stores info on the highest level of CO ever recorded. This feature will be very helpful when the emergency service workers arrive at your house.
  • Low-battery alarm. Does exactly what the title says: warns the homeowner whenever the battery charge goes dangerously low.
  • RC test. This is a cool feature that lets you test/silence the carbon monoxide detectors using a generic TV remote control.

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Carbon Monoxide: How Dangerous Is It?

Known as the “silent killer”, CO is a deadly chemical that only needs about 5 minutes to take someone’s life. It’s so lethal that leaving a car’s engine running with all the windows closed, firing up a camping stove or grill inside an enclosed room, or turning a generator on in a tightly-closed garage can kill you. In the US, exposure to carbon monoxide kills 430 people every year.

On top of that, approximately 50,000 people in the country go to the hospital (the emergency department, to be more precise) after they get poisoned by this gas. That’s why you should NEVER take it lightly. If your living room, bedroom, or kitchen is relatively small, it will take less time for carbon monoxide to accumulate and turn into a hazard. Even if one of the windows is open, breathing in CO can result in the death of an adult human or pet.

car exhaust
Image Credit: Alexander Ishchenko, Shutterstock

How Can You Protect Yourself From It?

Every time you warm up the car in the garage, fire the stove up, or use a portable generator, open the doors and windows for proper air ventilation. Heat furnaces, kerosene heaters, and even lanterns can all potentially pose a threat to your health. The thing is that any appliance or equipment that burns something (like charcoal, oil, kerosene, wood, or natural gas) will generate carbon monoxide.

And remember: the colder it is outside and the harder your heating system works, the more careful you need to be. That’s because there will be more CO in the air. This is especially true if you live somewhere up north where it’s cold most of the year. The best way to keep the risk of poisoning to a minimum is to invest in an advanced carbon monoxide alarm/detection system.

Install a detector on every floor (ideally, in every single room) and set the alarm to a low ppm so that it goes off the second CO levels start going up. Also, have all the pipes, tubes, and everything in between in the heating system checked by a licensed specialist. Do this once a year along with cleaning the flue pipes, vents, and the chimney. Feel like you’re being poisoned? Leave the house and call 911 immediately!

Common Signs of Carbon Monoxide Exposure

Feeling dizzy, weak, or having a mild headache? Chances are, you’re breathing in toxic carbon monoxide gas. Once the chemicals find their way into the lungs, they can make your chest hurt. Pay extra attention to these symptoms. While they could very well be caused by something else, you should still sound the alarm and have your entire family leave the house.

Speaking of alarms, a properly installed detector should be able to reveal high levels of CO before it puts your life and the lives of your loved ones in danger. The worst thing about carbon monoxide poisoning is that you can die in your sleep without experiencing any of the side effects. So, pay a bit extra, but do get a decent set of detectors that you’ll be able to hear no matter how soundly you’re sleeping.

•You might also like: Can You Use Wood in a Charcoal Grill? Will It Work?

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Carbon monoxide is a lethal gas. And, since we all have at least one fuel-burning appliance or equipment in the house, we’re all at the risk of being exposed to it. The good news is that there’s no shortage of CO detectors on the market, and most of them come at a reasonable price. They do have their own strong sides and weaknesses, of course.

So, before you take a pick, it’s important to know about the different types of detectors and sensors and what sets them apart. Today, we checked them all out and talked about their expected lifespan, pricing, ease of use, and more. Choose wisely, use our tips as a guide, and protect your home from the “silent killer” for good!

Featured Image Credit: Leena Robinson, Shutterstock


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