In high-rise buildings, what is the term for the tendency of heat and smoke to rise and spread laterally when encountering obstructions?

The correct term for the tendency of heat and smoke to rise and spread laterally when encountering obstructions in high-rise buildings is mushrooming. This phenomenon occurs when heat and smoke, instead of dissipating upwards, can spread out horizontally upon encountering ceilings or other obstructions. This lateral spread can create a dangerous situation for occupants and firefighters, as it can lead to rapid fire spread and increased difficulty in evacuating the building safely.

Mushrooming is particularly relevant in high-rise structures due to the unique architectural features like large floor areas and the potential for confined spaces, which can significantly impact fire behavior. Understanding this concept helps firefighters anticipate the movement of heat and smoke during an incident in a high-rise environment, allowing for better tactical decisions.

On the other hand, stratification refers to layers forming in smoke and heat but does not capture the lateral movement aspect associated with mushrooming. Flashing is related to the rapid heating of materials that can lead to fire, and convection refers to the process of heat transfer through fluids (like air), but does not specifically address the unique behavior of smoke in the context of high-rise buildings.