Technical Booklet K Ventilation·Page 76·D8
Cautions when reducing external air intake
Reducing external air inflow will also reduce outflow of internal air, causing buildup of internally generated pollutants, and modern buildings with low ceiling heights may not have sufficient fresh air reservoir capacity.
However, care must be taken since, e.g. reducing the inflow of external air will also reduce the outflow of internal air, resulting in a build-up of internally generated pollutants that need to be removed. Most modern buildings have low ceiling heights and therefore the concept of a substantial "fresh air" reservoir available within the building may not apply.
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