An extensive review and study of available equipment, materials, and procedures was conducted to develop an alternate testing method for evaluating laboratory fume hood performance. The equipment investigated included photo-ionization, infrared, gas chromatographic, and fluorimetric types. A sulfur system was designed employing a commercially available Leakmeter and sulfur hexafluoride as the tracer gas. The procedure is recommended for application as a 'Pre-Purchase' requirement, and when properly adapted will assure only properly designed units are obtained. Of prime importance is the applicability to all types of hoods from basic to auxiliary supply air models and all aerodynamic features can be evaluated. Hood losses, well below the tolerable limits can be detected, and capture efficiencies of auxiliary air models accurately defined.