Available at: https://digitalcommons.calpoly.edu/theses/3369
Date of Award
6-2026
Degree Name
MS in Polymers and Coatings
Department/Program
Chemistry & Biochemistry
College
College of Science and Mathematics
Advisor
Erik Sapper
Advisor Department
Chemistry & Biochemistry
Advisor College
College of Science and Mathematics
Abstract
Wildland-urban interface (WUI) fires and residential conflagrations present significant challenges for post-fire damage and fire propagation analysis. CAL FIRE observed reddening in architectural coatings during the 2025 Pacific Palisades fire with no determination of the cause. While heat-induced color change of infrastructure coatings has been studied, its potential use as a thermal exposure indicator in residential fire events remains largely unexplored. The objective of this study was to characterize the heat-induced color change of yellow iron oxide containing coatings subjected to thermal exposures, replicating residential fire conditions. The coatings were applied to commonly used building materials and exposed to direct flame and convective heat conditions under controlled laboratory settings. Coating discoloration was evaluated using CIELAB color space to quantify color change. Results demonstrated that coating discoloration was strongly influenced by short-term, high-temperature exposure. These findings indicate that the color change CAL FIRE observed may be due to the presence of iron oxide within the coatings. Existing architectural coatings may serve as indicators of thermal exposure following residential fire events. This work provides a foundation for future post-fire forensic analysis methods and may contribute to fire propagation and damage assessment tools for WUI.