NFPA National Fire Alarm and Signaling Code (NFPA 72) Practice Exam

The critical feature of smoke detectors in residential buildings is that they should be installed in all levels of the dwelling. This is essential for ensuring comprehensive coverage and enhancing the safety of occupants. Smoke detectors work by sensing the presence of smoke as an indicator of fire, and having them on every level means that any smoke generated from a fire will be detected as early as possible, allowing for timely alerts and actions.

Installing smoke detectors only in certain areas, such as just the attic or only outside, would create blind spots where smoke could accumulate without being detected. Similarly, while interconnecting detectors can improve efficiency, the foremost priority is ensuring that there is adequate coverage throughout the entire living space. Thus, the directive to install smoke detectors on all levels aligns with safety best practices as outlined in the NFPA 72 and is a fundamental aspect of residential fire alarm systems.