One of the main problems about air flows pattern studies remains the experimental validation of numerical codes developped for interzone air flow and polluant diffusion prediction. A few years ago, CETHIL developped a real scale experiment made of a 88m² dwelling built in our laboratory hall in a controlled climatic environment.
A humidity controlled exhaust fan have been tested during the winter season 1991/2. The test have been carried out in a detached one storey house with a flat roof. The relative humidity (RH) have been measured in the following modes: * natural ventilation only* wall mounted fan, setpoint 70% RH, and natural ventilation * fan in the exhaust duct, setpoint 70% RH.The relative humidity levels have been monitored in the shower room and in the other part of the dwelling. The temperatures have been measured in the exhaust duct and in four places in the dwelling.
The house dust mite inhabits bedding and soft furnishings in homes. It is implicated as a major cause of allergic asthma. Maintenance of indoor humidity below a level of 7 g/kg inhibits the growth of the mite population. A pilot survey was carried out by EA Technology in cooperation with the Building Research Establishment to investigate the effect of mechanical ventilation with heat recovery (MVHR) both on indoor humidity and mite abundances.