Facilities for fabrication of semiconductor devices utilize various gases that are hazardous due to toxicity, flammability and/or explosiveness. Distribution of these gases to the process equipment requires installation of systems which integrate the concerns of safety with gas purity to allow successful device manufacturing. This paper will outline overall distribution system design criteria and discuss utilization of exhaust ventilation to obtain some of these goals. Aspects of the system design that minimize the required exhaust will also be discussed.Units: SI