Case Study: Beam depth = 30 cm | Ceiling height (H) = 3 m.
(Note: Since depth is exactly ≤ 10 % of H, it follows the "Shallow Beam" criteria).
1. Spacing Requirements
When beam depth is less than or equal to 10% of the ceiling height (0.1H):
· Requirement: Standard smooth ceiling spacing may be utilized, regardless of the spacing between individual beams.
· Technical Justification: The ceiling jet (the layer of hot smoke and gases) typically occupies the upper 10% of the ceiling height. If beams do not protrude beyond this layer, they will not significantly impact the smoke detector response time.
2. Mounting Locations
For spot-type smoke detectors, the following mounting options are permitted:
· Ceiling Mount: Installed directly on the ceiling surface between beams.
· Beam Mount: Installed on the underside (bottom) of the beams