Carbon Monoxide Detectors
Odorless, colorless, poisonous, and deadly, carbon monoxide (CO) is known as the “silent killer.” A byproduct of most combustible fuels—including oil, gas, wood, kerosene, propane—there’s dangerous opportunity for CO poisoning in our homes. All it takes is an often unnoticed malfunction in a fireplace, space heater, water heater, stove, furnace or other household necessity to leak carbon monoxide into the air we breathe to cause sudden illness (flu-like symptoms such as headache, fatigue, dizziness) or even death.
The Centers for Disease Control reports and average of more than 400 deaths each year from unintentional, non-fire related CO poisoning. In response, many states and local jurisdictions now require CO alarms in residences.
How Carbon Monoxide Detectors and Alarms Work
Carbon monoxide alarms monitor the build up of carbon monoxide over time in your home, sounding an alarm if elevated levels are detected. Most carbon monoxide monitors use one of four types of sensors:
- Electrochemical sensors produce and measure a current related to the amount of carbon monoxide in the air. They are the most accurate and most efficient type of sensor, requiring minimal power and are long-lasting.
- Colorimetric sensors rely on a chemical color pad which changes color upon reaction with CO. They can take up to 48 hours to reset after they sound. They are the least expensive type of carbon monoxide sensor, but offer minimal protection.
- Metal oxide semiconductor sensors must be hardwired or plugged in because they require heat to operate. They measure the resistance of oxygen versus CO on metal wires. Overly sensitive to other gases, false alarms may occur.
- Biometric sensors use biotechnology to sense the presence of CO by monitoring infrared photons. They are most popular in hotels and hospitals because they do not false alarm in the presence of cleaning agents or air fresheners, but they are also the most expensive type of CO detector sensors.
Carbon Monoxide Alarm Options
- Battery powered CO monitors are easy to install, but require regular battery replacement.
- Hard-wired detectors are connected to your home’s electrical system. Having a battery back-up for your CO detector is recommended in case of power outage.
- Digital CO alarms provide a constant readout of CO concentration in parts per million, and track past levels as well.
- Dual CO/fire detectors alert against both CO and fire dangers, many via voice warning that specifically calls out fire or CO.
- Monitored devices that are connected to the control panel in a home security monitoring system. CO levels trigger the home alarm and alert the monitoring company, which dispatches emergency services.
What to Look for in a Carbon Monoxide Detector
- Choose a CO monitoring device with an electrochemical sensor for optimal accuracy, fewest false alarms, and least use of power.
- A battery-powered carbon monoxide alarm provides continued protection during power outages.
- Choose dual CO/fire detectors if you need to install both, which will save money and space.
- A digital detector gives constant readings of CO levels, which can mean early attention to potentially dangerous situations.
- Consider making a carbon monoxide detector part of a home security system with constant monitoring from a monitoring service, which alerts you even when you’re not home, and immediately dispatches emergency services.