A new approach to characterize firebrand showers using advanced 3D imaging techniques.

A new approach to characterize airborne firebrands during Wildland-Urban Interface (WUI) fires is detailed. The approach merges the following two imaging techniques in a single field-deployable diagnostic tool: (1) 3D Particle Tracking Velocimetry (3D-PTV), for time-resolved mapping of firebrand 3D trajectories, and (2) 3D Particle Shape Reconstruction (3D-PSR), to reconstruct 3D models of individual particles following the Visual Hull principle. This tool offers for the first time the possibility to simultaneously study time-resolved firebrand fluxes and firebrand size distribution to the full extent of their three-dimensional nature within a control volume.