Carbon monoxide is a poisonous gas that you can't see, smell, or taste, which makes it especially dangerous. It forms when fuels like gasoline, wood, coal, or natural gas don't burn completely because there isn't enough oxygen.

When people breathe carbon monoxide, it prevents their blood from carrying oxygen properly, which can make them sick or even cause death. That's why homes have carbon monoxide detectors, small devices that beep loudly if they sense this gas in the air. These detectors save lives by warning families to get outside and call for help.

Carbon monoxide can build up from car exhaust in closed garages, from furnaces that aren't working right, from generators running indoors, or from grills used inside. Firefighters and emergency responders take carbon monoxide very seriously. They know that proper ventilation (letting fresh air flow through) and working detectors are essential for keeping people safe.

The gas is sometimes called CO for short, using the chemical symbols for carbon and oxygen. Understanding carbon monoxide helps explain why certain safety rules exist, like never running a car in a closed garage or making sure camping tents stay well-ventilated when using portable heaters or stoves.