Unravelling the mysteries of fire

Understanding the complex physical and chemical processes governing fire phenomena is crucial for advancing fire safety science and validating predictive models. Advancement in this field is intrinsically linked to development and application of temporally and spatially resolved diagnostics capable of making quantitative measurements in harsh, unsteady fire environments spanning a wide array of scales. This review provides an overview of state-of-the-art in fire diagnostics, with focus on the diverse suite of modern, advanced, non-intrusive methods. Probe-based instruments are ubiquitous in fire research, providing foundational data across the field. Advancements in camera and laser technologies have enabled use of spectroscopic methods and video mapping for comprehensive monitoring of fire experiments, providing invaluable real-world data. Adaptation of modern combustion diagnostics, while not without significant challenges, has revolutionized experimental fire research. Options span from advanced laser diagnostic techniques for point measurement of temperature, velocity, gas concentration and particulates to planar, 3D and 4D systems, deployable over larger areas. Integrating thermal imaging, spectroscopic techniques and high-speed photography has advanced multi-scale fire research in topical areas like suppression, smoke evolution and fire dynamics. In future, robust, comprehensive suites of simultaneous multi-parameter measurement diagnostics will enable on-going advancements in both fundamental research and practical fire safety applications.