Efficiency measurements of kitchen hoods.

Air extraction in the kitchen is an essential element in all ventilation strategies for dwellings. This can be done by natural ventilation or mechanical extraction. In practice, the use of mechanical kitchen hoods is very common in Belgium. As part of a research carried out for the Belgian IWONL/JRSIA, the laboratory for Hygrothermics and Indoor Climate of BBRI carried out measurements to evaluate the efficiency of kitchen hoods. The test procedure applied at BBRI is a mix-up of two existing standards. The major difference between the two standards is the use of an interference device to simulate occupants behaviour. Just this interference device seems to have a crucial influence on the collection efficiency of a kitchen hood. Besides the determination of the collection efficiency, a definition is given of a pollution index. This index evaluates the pollution level in the room when using a kitchen hood. Also a method is explained to design and to evaluate a kitchen hood installation taking into account air flow characteristics and collection efficiencies.