HVAC Air Systems: Exhaust Optimization


Exhaust airflow rates are typically dictated by process equipment exhaust specifications. Equipment manufacturers’ suggested exhaust quantities have been found to be overstated and not science based. For example, a recent study by International Sematech found that exhaust airflows could be reduced in four devices typically found in semiconductor cleanrooms: wet benches, gas cabinets, ion implanters and vertical furnaces. The results of the study reported that a reduction of total exhaust airflow by 28% exists among the four devices tested. The same study, which measured fume capture and containment effectiveness, found one piece of equipment where an increased exhaust rate was required to maintain safe containment.