A discharge coefficient equation was incorporated into a mass balancing procedure to compute the elevation of the neutral pressure axis (NPA) for a general distribution of openings. An equation was developed to compute the discharge coefficient of an arbitrary opening as a function of the three dimensional geometry, the pressure difference, the total minor loss coefficient, and the air properties.

The importance of the climate to general health and wellbeing has long been understood. The ultimate goal for planning, building, renovation and administration of the housing stock is to satisfy people's needs. When this goal is not attained, the results will be human sacrifices, social problems and losses to the national economy. This, of course, also applies to the issues of climate and the environment. Research and development work on these questions is nothing new for the Swedish Council for Building Research (BFR).