What type of interior fire pattern is most likely to vary widely in appearance?

Ventilation-generated patterns are influenced by a number of variables, such as the amount and direction of airflow into a structure, the location of openings, and the materials present in the environment. This variability in airflow can lead to different fire behavior and characteristics, which results in a wide range of potential fire patterns on surfaces. Depending on how ventilation is manipulated or affected by factors such as wind or door openings, these patterns can shift dramatically, making them less predictable.

In contrast, fuel-generated patterns are typically more uniform since they depend primarily on the fuel's characteristics and how it burns, rather than external conditions. Similarly, combustion-generated patterns relate more closely to the chemical processes involved in burning, which, while they can vary, do not reflect the same degree of variability as those driven by external air movement. Heat-induced patterns result from the thermal effects of fire, which also tend to follow more consistent behaviors based on the heat intensity and the duration of exposure. Thus, the nature of ventilation's impact on fire dynamics leads to a greater range of appearances and outcomes in the patterns observed.