Evaluation method

The implementation of decentralised ventilation units is growing, especially in the residential retrofit. These systems are typically simple to install on site (usually in the external façade with no additional ductwork) and allow room-by-room control strategies. Until now, decentralised systems are evaluated by applying the same methodologies as for centralised ventilation systems, even though different boundary conditions apply. Some differences are for example:  

With the occurrence of indoor terrorism attacks and the accidental release of toxic chemicals, people have paid more attentions on such emergency events in recent years. The effective evaluation method of emergency ventilation strategies could help people find out the accurate way to control the ventilation system, and reduce the total loss during the event. In this article, two methods to evaluate the effect of ventilation are compared. One is based on Efficiency Factor of Contaminant Source (EFCS). The other is based on Exposure Risk (ER) and Population Risk (PR).