Computer rooms.

   

Calculation model for airtightness and natural ventilation of buildings. Rakennusten tiiviyden ja ilmanvaihdon laskentamalli.

A multi-cell calculation model was developed for calculation of the interconnections between airtightness, air change rates, pressure conditions and energy consumption. The flow equation used in the model is quadratic, which can be used as well for a single leakage path as for a whole building envelope. For energy calculation the area of wind directions is divided into12 sectors (each 30 degrees) plus one sector for calm wind conditions. The mean values of wind speed and outside temperature applied to each wind sector are calculated from weather data of several years period.

Methods for measuring the airtightness and air change rates in buildings. Rakennusten ilmanpitavyyden ja ilmanvaihtuvuuden mittausmenetelmat.

In these instructions for measuring the airtightness and air change rates in buildings, the principles of measurement methodics, the need for measurements and choosing the correct method for different purposes, are presented. Details of measuring are described for the most common methods: the pressure test, the collector chamber method for measuring local leakages, and the tracer gas methods. In addition, other methods and auxiliary measurements are presented.

Radon and lung cancer - incremental risks associated with residential weatherisation.

Uses a model to estimate the incremental risk of lung cancer associated with increased radon concentrations in indoor air resulting from decreased air infiltration caused by increased air tightness of dwellings. Gives results for selected changes in the air exchange rate. Discusses findings.

Measurement of carbon dioxide of the indoor air to control the fresh air supply.

In order to save energy, i.e. ventilation heat losses, the fresh air change rate should be adapted to the prevailing need. Even though it is a fact that reducing the fresh air change rate will result in a ventilation heat gain, the fresh air flow rate should not be kept too low, so that pollutants, humidity and body odour can accumulate. The results of measurements in a climatic chamber and in a lecture theatre show a significant relationship between the concentration of carbon dioxide and body odour of the indoor air under nonsmoking conditions.

Householder response to airtightness information.

20 low-income family houses were studied for Air Changes per Hour and Equivalent Leakage Area as measured by the Blower Door Test during the winter of 1985-86. The residents of 10 of these homes were given instruction on air sealing techniques and were provided a "starter kit" of retrofit materials. Upon retesting, these 10 homes showed no improvement in either ACH or ELA,indicating either a lack of interest on the part of the householders in making their homes more airtight, or an inability to do so based upon insufficient information or physical limitation.

Gravity driven flows through open doors.

Occupants can significantly influence both the heating energy requirements and the indoor air quality of a building by opening and closing doors and windows. If the effects of these actions are to be accurately estimated, both the quantity and character of these exchange flows must be determined. In this paper, data on gravity-driven exchange rates through open doors obtained from field experiments at the Alberta Home Heating Research Facility are compared with laboratory model simulations and theoretical predictions.

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