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Analysis of low particulate size concentration levels in office environments

Simulation methods and test results are presented here to confirm projections of actual total suspended particulate (TSP) concentration levels for representative office buildings, with particular emphasis on the 0.3 to 5 micron particulate si

Indoor air pollution - Some Canadian experiences

It is only recently that indoor air pollution has begun to attract the attention it deserves in Canadian Governmental and Building code circles. Two main events have been catalytic towards this increased emphasis. First, the ban on the use of ur

Disturbances in ventilation systems. Part 1 and Part 2

The quantity of air in several rooms lying in a stack connected by means of fresh air and exhaust air ducts is considered as a simple model of amultistorey building. Negative pressures set up within the rooms can be equalised by adjusting the

An evaluation of formaldehyde sources exposures and possible remedial actions in two office environments

In response to employee complaints of upper respiratory and eye irritation, formaldehyde air sampling studies were conducted in two different office environments. The first was in a series of temporary modular buildings with construction simi

Natural ventilation - auxiliary ventilation. Naturliche Luftung - unterstutzende Luftung.

Discusses whether air conditioning could be replaced. Treats the evolving concept of constructing office buildings designed to meet comfort conditions by natural ventilation, with mechanical ventilation, cooling and humidification applied only during the coldest parts of the winter and hottest periods of the summer. Describes the practical application of this concept to three office buildings in West Germany.

Evaluation methods for air velocity measurements in air-conditioned rooms.

The uncertainty of measurement results of air velocities in air-conditioned rooms generally is very high. A considerable part of the measurement errors are caused by the evaluation methods. It is shown that the accuracy of results can be ameliorated by using suitable statistical methods without increasing the effort. In this case binomial distribution gives better results thenGaussian distribution. To optimize the duration of measurements the most favorable reading interval must be determined. This time interval can be defined by the autocorrelation function of air velocity.

Air flow experiments in full scale test rooms.

Airflow inside air-conditioned rooms needs to be determined experimentally using test rooms. The test room dimensions vary because a test room must represent a section which is characteristic of the original room dimensions. The flow pattern is made visible; the velocities, and in some cases the gas concentration is measured. The experiments are done under thermal steady-state conditions. Some general results are:

Room flow tests in a reduced scale.

The study concerns the problems and prediction of room flow in air-conditioning. It is shown how difficult it is to form mathematical models, especially of the three-dimensional flow field occurring in practice. After basic definitions, an explanation of the influence of different air flow systems on the structure of room flow is given. The microstructure of the flowis so complex that a precise mathematical model formation seems to be impossible. Measurements on isothermal and models(reduced from the original)supply reliable three-dimensional results.

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