Under what conditions is spacing reduced for heat detectors on a beam type ceiling?

In the context of beam-type ceilings, heat detectors are typically required to be installed closer together at certain ceiling heights to ensure effective coverage and reliable detection of heat. When the ceiling height is between 10 and 30 feet, the spacing can be reduced because the heat generated by a fire may not rise as effectively to the level of the detector if it is placed too far away.

This specific ceiling height range allows for more efficient heat detection since the design and thermal dynamics at these heights make it necessary to have detectors closer together to capture any potential heat signatures from a fire before they spread.

In contrast, at lower ceiling heights (like 5-15 feet), the heat detection is generally more effective due to proximity to the heat source. For higher ceilings, like 20-40 feet, the effectiveness of heat detectors might allow for wider spacing, as the heat can reach them more effectively from a taller source. Therefore, the spacing is specifically reduced between 10 and 30 feet to maintain optimal fire safety standards.