Energy Efficiency and Exhaust Devices
Devices that exhaust air from laboratories have evolved in response to increasing concerns that they function as "primary safety barriers." These design changes have also resulted improved their energy consumption. Some basic principles of energy-efficient laboratory exhaust include:
·Safety features, such as entrance air foils, must be included in specified fume hoods to insure energy efficient operation.
·A laboratory's exhaust volume is directly proportional to the fume hood face velocity. The higher the stipulated face velocity, the greater the amount of laboratory exhaust volume and energy use.
·In choosing face velocity, energy engineers must consider the "room air challenge," that is, the disruptions presented to the fume hood face velocity caused by, for example, the operator's movements in the laboratory.
·Biological safety cabinets (BSCs) are constant volume exhaust devices; energy savings result when the intake velocity and the cabinet's opening area are minimized by using the appropriate "Class" and "Type." Using an energy-saving VAV system compensates for dynamic HEPA filter loading over time and different cabinet operational modes.
·Glove boxes, which can be used instead of BSCs, have substantially reduced exhaust than BSCs. Therefore, they offer an interesting energy-saving alternative to BSCs.
Fume hood face velocity
Room air challenge
Biological safety cabinets