According to Lentz and Seth (1989), the following points need to be evaluated before diversity is considered in sizing the HVAC system:
·The ventilation system must be large enough to warrant diversification. There is little point in using this technique on small projects with only a few fume hoods. Simultaneous usage of the fume hoods is more likely in a small facility.
·The minimum level of air flow allowed by users, safety officials, and owners must be significantly lower than the maximum fume hood exhaust flow. There is debate over whether or not exhaust air-flow rates can be diversified.
·System oversizing in anticipation of future expansion limits the reduction of installed system capacity.