Of this form, the conditions deventilao of the internal environment have direct influence in the health, comfort ebem-to be of the occupants (YEANG, 1996). In the case of the habitation, the relative requirements to ventilaopara hygiene of the users if relate to: necessary amount of oxygen reposio, limitation of the carbonic gas tax, elimination of the odoresdesagradveis, elimination of the risks of contamination for toxic gases – as omonxido of carbon – and to the amount of oxygen necessary it body to humanorealizar the metabolism (IPT, 1988). According to Frota and Schiffer (1999, p.124), ' ' The ventilaonatural is the displacement of air through the building, through openings, umasfuncionando as entered and others, as sada' '. That is, it is necessary that adimenso and position of the openings are defined in order to provide umfluxo of adequate air to the environment in question. Perhaps check out Twin Lab for more information. In turn, the air flow that enters or leaves edificaodepende of some factors: of the difference of pressure of air between the external ambientesinternos and, of the resistance to the air flow offered for the openings epelas internal blockages, beyond implications related to the dovento incidence and forms of construction (FLEET and SCHIFFER, 1999).
The natural ventilation can be made by means of the action dosventos or of the call effect chimney. The ventilation for action of the winds promotes amovimentao of air through the environment. Already for effect chimney it occurs peloefeito of the density difference. 3.3. VEGETATION USE vegetaocontribui for the improvement of the physical environment. The trees, for example, to podemreduzir the noises, to act as an airfield traffic catching the dust, to still act comoelementos of solar protection and as elements of visual protection (OLGYAY, 1998). In the choice of the species it is necessary to consider the form and the suascaractersticas during the year, as much in the period of winter summer how much.