An estimate of the variation of non smokers' lung cancer risk from passive or involuntary smoking is given as a function of ventilation rate in a typical office, at an occupancy of 7 persons/100m2 as specified under ASHRAE standard 62-1981.
For the transient analysis of the thermal and moisture conditions in multilayer constructions a numerical algorithm and a computer program based on the Crank-Nicholson method and quasi linearisation are formulated. Temperature and moisture content are used as transport potentials. In energy balance equations and conditions, convention and accumulation of moisture, the diffusion flow of water vapour, the capillary and surface diffusion flow of liquid water and the viscous flow of humid air and water are considered. The boundary layer and interfacial balance equations are derived.
The Department of Building Technology, the Technological Institute of Copenhagen, have for several years been developing equipment for continuous measurement of air infiltration. It enables continuous measurement of air change rate in up to ten rooms, the constant concentration method with tracer gas is used, and the results are recorded on a computer diskette during measurement. Analysis of possible measuring errors show that the method is accurate and to within plus or minus 5%. Shows the results of measurement of air infiltration in 10 relatively airtight dwellings.
There have been considerable efforts to estimate risks to health from the present level of indoor air quality. However, there has been comparatively little work to relate these calculated risks to other risks of energy use or conservation, or to determine how large these risks will be in the future. This paper finds that, on the basis of extrapolated trends, risk associated with changes in indoor air quality in the United States. The other two are associated with the expected change to smaller automobiles and the entire coal fuel cycle, from producing electricity to synthetic fuels.
This is the second part of a study on natural ventilation in functional buildings. Reports the results of 23 measurements on a number of partitions, internal walls and one brick built internal wall. Measurements were made in 4 buildings. For the largest leakages measured in these 4 buildings, a strong influence was observed on the ventilation of neighbouring rooms. The opening of a window in a room has notable consequences on the ventilation and air flow in the other rooms. The measured air leakages ranged from 0038 to 0.068 m2 for a wall and .0131 -.0529 m2 for a room.
After a brief treatment of the ideas and aspects that play a role in ventilation, gives a general outline of chosen investigation methods, with a concise review of apparatus and calculation models used. Presents a review of the ventilation investigations carried out by IMG-TNO during the last 10 years in factories, labs, hospitals, auction halls etc.
Presents methods for the measurement of air flow rates, including methods for measuring flow in ducts, at exhaust and supply air devices and for air change rates for using tracer gas.
Presents a simplified method for estimating heat consumption in buildings. The basis of the method are presented, along with an example of how to apply it. The method requires climatic data in a specific form and the way to calculate this is also discussed. Finally, gives some comparisons between results from this method and detailed computer simulations.
Deals with the problems of open building passages and tunnel like entrances caused by thermal influences and wind currents. Shows advantages of air screening, especially where high pressure differences occur.
Describes the CO2-controlled ventilation system of the energy efficient EKONO II office building in Helsinki. An air sample is taken from a main return air duct, pumped to a CO2 analyzer which gives the message of the concentration tothe computer. The computer regulates the opening of the recirculation air and outdoor air dampers to keep the CO2 concentration in return air below a certain level. Shows fluctuation of outdoor air rate and CO2 concentration during one day.