English

Internationally there are many different requirements and regulations for ventilation.  Sometimes the variation is more than a factor of five. There are strong drivers to reduce energy consumption for HVAC, and therefore the spread in requirements and regulation is worthwhile to study. To reduce ventilation flows there is a necessity to understand the reasons behind. Demand control to reduce this flows is in many countries growing but the control parameters are quite different, for instance humidity versus CO2 control.

The British Standard Code of Practice, and other authoritative guides, recommend minimum rates of ventilation related to the size and use of rooms, and structural means for providing them. But the difficulty of measuring actual ventilation rates suggests that it is seldom done.