Miller, John Herbert ThomasAccurate obscuration levels at the response time of photo-electric smoke detectors are needed for proper detection modeling and analysis. In recent works, obscuration meters were used to measure the obscuration level at photo-electric detector response. In this study, aspirated smoke detectors (VESDA) were used to measure this same obscuration level. These detailed measurements were used to reduce the ambient light and the technology difference error associated with the obscuration meters. The use of aspirated smoke detection (VESDA) instead of light obscuration meters displayed increased accuracy for a majority of the experiments conducted in the 2008 report titled "Validation of a Smoke Detection Performance Prediction Methodology" involving flaming and non-flaming incipient fire sources at 3 different ventilation conditions.ThesisEngineering, Generalaspirated smoke detectordetector responseobscurationphoto-electric smoke detector