A carbon monoxide (CO) detector is a safety device designed to detect the presence of the odorless and colorless gas carbon monoxide, which can be deadly, and alert occupants with a loud alarm. 

Here's a more detailed introduction:

What it is:

• A carbon monoxide detector, also known as a CO alarm, is a safety device that monitors the air for the presence of carbon monoxide. 

• CO is a toxic gas that can be produced by various fuel-burning appliances, such as furnaces, water heaters, and fireplaces. 

• It's crucial because CO is invisible and odorless, making it difficult to detect without a CO detector. 

Why it's important:

• Carbon monoxide poisoning can cause serious health problems and even death. 

• Early detection and warning from a CO detector can allow people to evacuate their homes and seek medical attention, potentially saving lives. 

• The U.S. Consumer Product Safety Commission (CPSC) recommends that every home should have a carbon monoxide (CO) alarm. 

• The International Association of Fire Chiefs recommends a carbon monoxide detector on every floor of your home, including the basement. 

How it works:

• CO detectors typically use electrochemical sensors to detect the presence of carbon monoxide. 

• When the sensor detects a dangerous level of CO, the detector will sound a loud alarm, alerting occupants to the danger. 

• Some CO detectors also include a digital display that shows the CO level. 

Types of CO detectors:

• Battery-powered:
  These are easy to install and can be placed anywhere, but they require regular battery replacement.

• Plug-in:
  These detectors plug directly into a wall outlet and do not require installation.

• Hardwired:
  These detectors are connected to the home's electrical wiring and often have a battery backup. 

Where to place them:

• Every level of the home: Install CO detectors on every level of your home, including the basement. 

• Near sleeping areas: Place detectors within 15 feet of each room used for sleeping. 

• Near potential sources of CO: Install detectors near or over any attached garage, and near potential sources of CO, such as furnaces, water heaters, or fireplaces. 

• Follow manufacturer's instructions: Always follow the manufacturer's instructions for installation and maintenance.