M. Mysen
Bibliographic info:
Air Information Review, Vol. 25, n° 1, Dec 2003, pp 5, 1 Fig.

In Norway and Sweden's schools, hybrid or natural ventilation with ground-coupled fresh air intake ducts (or culverts) is the popular way of conditioning air.The ground-coupled ducts are normally made of concrete and easily accessible for inspection and cleaning; they can be divided into two parts: the air-intake culvert and the air-distribution culvert. Measurements show that the use of ground-coupled ducts along with a suitable airflow regulation is a guarantee that the supply air is colder than room air.