What Does a Carbon Monoxide Detector Do and How Does it Work?

Written by | Updated October 12, 2018

It might seem like a time-saver to run your car in the garage before a long commute, especially on a cold winter’s morning. But the emissions from your car can fill up your garage with a dangerous, silent threat, even if the door is open. Carbon monoxide (CO) is an odorless, colorless, and toxic gas that claims almost 430 lives a year.1

It’s a byproduct of burning carbon fuel like the natural gas in your stove and the gasoline in your car. Even small doses of carbon monoxide can cause permanent damage or death.

What is carbon monoxide?

Carbon monoxide gas is made of one part carbon and one part oxygen. Carbon monoxide comes from incompletely burned carbon fuel like wood, gasoline, coal, propane, natural gas, gasoline, and heating oil.

When burned in an open area with plenty of ventilation, these energy sources aren’t dangerous. Carbon monoxide is hazardous only in a confined space like a basement, kitchen, garage, or camper.

Why is carbon monoxide dangerous?

Carbon monoxide is deadly because it’s so hard to detect without a carbon monoxide sensor. Once it passes into your lungs, it binds with your red blood cells and starves your body of oxygen.

Common symptoms of carbon monoxide poisoning include intense headache, nausea, vomiting, dizziness, fatigue, and weakness. Disorientation and unconsciousness can occur when CO reaches levels of 150 ppm or parts per million.2

Perhaps most troubling is that before symptoms turn lethal, they may appear as cold or flu symptoms like shortness of breath, nausea, or mild headaches. Carbon monoxide is the second-leading cause of poisoning in the US with the highest risk in Wyoming, Alaska, and Montana.

kidde-nighthawk-plug-in-co-gas-alarm

Kidde Nighthawk

How do you detect carbon monoxide?

Carbon monoxide detectors are the fastest way to prevent carbon monoxide poisoning. You can install a carbon monoxide detector (or multiple detectors) in your home. They work much like your fire or smoke alarm by sounding an alarm when they detect carbon monoxide. You can find simple models like the Kidde Nighthawk that set off a siren or smart detectors like the Nest Protect that connect to your phone or home security system.

How do carbon monoxide detectors work?

Carbon monoxide detectors sound an alarm when they sense a certain amount of carbon monoxide in the air over time. Different sensors set off different types of alerts.

  • Biomimetic sensor: a gel changes color when it absorbs carbon monoxide, and this color change triggers the alarm.
  • Metal oxide semiconductor: When the silica chip’s circuitry detects carbon monoxide, it lowers the electrical resistance, and this change triggers the alarm.
  • Electrochemical sensor: Electrodes immersed in a chemical solution sense changes in electrical currents when they come into contact with carbon monoxide, and this change triggers the alarm.

Once the alarm sounds, the carbon monoxide detector must be in a carbon monoxide-free environment to reset itself.

When will my carbon monoxide detector go off?

The CO alarm will sound if your sensor detects a high buildup of carbon monoxide in your home. Most people begin to feel the effects of carbon monoxide at 50 ppm, so be sure your detector can sense an amount of 50 ppm or less.3

What do I do if my carbon monoxide detector goes off? 

First, don’t panic. Gather everyone in your house and move outside for fresh air. Survey everyone’s health, and check for any flu-like symptoms that could suggest poisoning. If you notice any symptoms, call 911 immediately.

If you can, open all doors and windows to air out your home before heading outside. If possible, do not reenter your home until the alarm stops sounding or your home has been deemed safe by the authorities. Contact a professional to evaluate all of your fuel-burning appliances and any other possible sources of carbon monoxide to prevent a future incident. Be sure to prevent safety hazards in your home with regular maintenance and inspections.

Where should I place a carbon monoxide detector?

First, find out if your local laws require you to have a carbon monoxide detector in your home or business. You’ll want to have enough CO detectors to cover all the levels in your home, including the basement and attic. Place a CO sensor near each bedroom and anywhere required by local laws. Find out more about the best places to install CO monitors in your home.

What kind of carbon monoxide detector should I get?

There’s a surprising amount of variety in today’s carbon monoxide detectors. The simpler models plug into outlets or use batteries and alert you with a loud siren like the one your smoke detector has. These models are often cheaper and suitable for multi-room buildings that need several units spread throughout.

You can also find smart models that connect with your home’s security system or alert you of danger through a mobile app. If you have kids or pets at home, these could be a wise investment to keep them safe.

Overall, the best carbon monoxide detectors sense CO fast and alert you as soon as they do. No matter what type you get, be sure to test it frequently and make sure its power source is reliable and functioning.

How can I prevent carbon monoxide poisoning?

Carbon monoxide poisoning is a serious risk, but fortunately, it’s very preventable. In addition to installing sensors throughout your home, here are a few tips for avoiding a dangerous situation.

  • Never heat your home with a gas range. Gas stoves produce carbon monoxide and can fill your home with the dangerous gas.
  • Don’t run your car in the garage. If you want to warm up your vehicle in the winter, pull out of the garage first. Carbon monoxide is a common byproduct of vehicle exhaust, and it can build up quickly in a closed (and open) garage.
  • Always have proper ventilation. Running your generator, pressure washer, or any gas-powered engines in an enclosed area like a basement or garage without adequate ventilation can be extremely dangerous.
  • Always cook safely while camping. You should enjoy the wilderness safely. Don’t use a charcoal grill, hibachi, or camping stove inside your home, tent, or camper.
  • Install a carbon monoxide detector. The best carbon monoxide detectors are affordable, easy to install, and can save your life. We recommend installing one on every level of your home, near each bedroom, and near your garage.

Sources:

  1. Centers for Disease Control and Prevention, “Carbon Monoxide Poisoning (CO)
  2. United States Consumer Product Safety Commission, “Carbon Monoxide Questions and Answers
  3. Kidde, Fire Safety, “What Are the Carbon Monoxide Levels That Will Sound the Alarm?

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