What type of detector is required in any building that has fossil fuel burning equipment?

In any building that has fossil fuel burning equipment, a carbon monoxide detector is essential due to the risks associated with carbon monoxide (CO) exposure. Fossil fuels, such as natural gas, oil, and coal, release carbon monoxide as a byproduct of combustion. This colorless, odorless gas can accumulate indoors and pose significant health risks, including poisoning and even death.

The installation of carbon monoxide detectors is mandated by various codes and regulations in many regions, particularly because of the dangerous nature of CO. Unlike smoke detectors, which are designed to detect particulate matter from combustion, carbon monoxide detectors specifically sense the presence of CO gas in the environment, providing an early warning system that can save lives.

In summary, carbon monoxide detectors are critical in buildings utilizing fossil fuel appliances to ensure safety from potentially lethal gas exposure, making this the correct answer for the given question.