Domestic ventilation with variable volume flows.

The system of decentralized apartment ventilation has been successfully used for several years in multiple-storey apartment construction in the Federal Republic of Germany. With this tried and tested system, the individual apartments are vented into a common exhaust shaft with decentralized apartment ventilating fans. The special designs of the individual fans ensure a constant volume flow of the outgoing air in the individual apartments, in spite of the large pressure variations into the outgoing air conduits. Non-returnflaps prevent a back flow of the outgoing air.