The study successfully validated the use of salt-water analog modeling as an effective diagnostic, predictive and scaling tool for understanding fire dispersion in a beam-ceiling complex compartment using the Particle Image Velocimetry (PIV) and Planar Laser Induced Fluorescence (PLIF) techniques. Dimensionless dispersion signatures and front arrival times were compared between the fire and salt-water experiments which showed excellent agreement. Prediction of the detector lag times using fire and saltwater data agreed with that of fire experiments.