Final answer:
Carbon monoxide (CO) detectors are mandatory by law because CO is a colorless, odorless gas that can cause fatal poisoning. Detectors must be in near sleeping areas and potential CO sources. CO detection is crucial as it is impossible to sense without a detector and can cause death without warning.
Step-by-step explanation:
A carbon monoxide (CO) detector is required by law to be in place in residential homes and certain buildings to ensure the safety of occupants. It is critically important to have a detector specifically for carbon monoxide because CO is a colorless, odorless gas which can be lethal in high concentrations. Carbon monoxide poisoning can cause symptoms such as headaches, dizziness, weakness, nausea, and it can be fatal without warning since it can't be detected by human senses. CO is produced by common household appliances and vehicles that burn fuels, so proper installation and maintenance of these detectors are essential for preventing possible lethal exposure.
According to law, detectors must be installed in sleeping areas and in close proximity to any potential sources of carbon monoxide. These include areas near garages, heating systems, or any fuel-burning appliances. Early detection of increased levels of CO can prompt necessary actions to avert poisoning and save lives, which is why these detectors are mandated in homes and buildings.