What mechanism can halt the AHU serving a corridor in the event of smoke detection?

The correct answer to the question regarding what mechanism can halt the air handling unit (AHU) serving a corridor in the event of smoke detection is smoke detectors. Smoke detectors are designed specifically to detect the presence of smoke, which is a primary indicator of fire. In the context of building systems, when smoke is detected, these devices can trigger alarms and activate various safety protocols, including the shutdown or modification of the operation of heating, ventilation, and air conditioning (HVAC) systems like an AHU.

By shutting down the AHU, the spread of smoke throughout the building can be limited, thus enhancing the safety of occupants by preventing the circulation of smoke-laden air. This response is part of a larger fire safety strategy to protect lives and property within a building.

In contrast, while water suppression systems and other mechanisms may play important roles in fire protection, they do not specifically control the operation of AHUs directly in response to smoke detection. Thermostats regulate temperature but are not designed to detect smoke, and carbon monoxide alarms are important for detecting toxic gas but do not fulfill the specific function of responding to smoke detection in the same way that smoke detectors do.