Lines of demarcation are important for understanding:

Lines of demarcation are crucial in understanding the differences in fire effects on materials because they help investigators determine the boundaries where fire exposure has varied, which in turn influences how materials react to that exposure. These lines indicate the transition from areas that have been heavily affected by heat and flames to those that have not, allowing investigators to analyze and document the extent of damage accurately.

Understanding these differences is essential in fire investigations; it aids in the assessment of burn patterns, material degradation, and how different materials contribute to or withstand fire. By distinguishing areas based on their fire effects, investigators can draw more precise conclusions about the fire's origin, development, and potential causes, which is vital for determining the nature of the incident.