What does the ceiling jet refer to in fire behavior?

The ceiling jet refers to the horizontal movement of hot gases that occurs when a fire generates heat and smoke, causing the air near the ceiling to become heated and rise. As the hot gases ascend, they spread out horizontally along the ceiling, forming a jet of heat and smoke that can travel several feet away from the fire source before falling back down to lower levels. This phenomenon is significant in understanding fire behavior as it helps explain how heat and smoke distribute within a compartment during a fire.

This knowledge is critical for safety officers and firefighters when assessing fire conditions and risks within a structure. Recognizing the ceiling jet can aid in effectively strategizing ventilation, rescue operations, and firefighting approaches, as areas under the jet may become hazardous due to increased temperatures and poor visibility caused by smoke.