Definition for word: Natural Ventilation

Ventilation using only natural air movement (through an open window, for example), without fans or other mechanical devices.

Referrence from

is the process of supplying and removing air through an indoor space by natural means. There are two types of natural ventilation occurring in buildings: wind driven ventilation and stack ventilation. The pressures generated by buoyancy, also known as 'the stack effect', are quite low (typical values: 0.3 Pa to 3 Pa) while wind pressures are usually far greater (~1 Pa to 35 Pa). The majority of buildings employing natural ventilation rely primarily on wind driven ventilation, but stack ventilation has several benefits. The most efficient design for a natural ventilation building should implement both types of ventilation.

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