Smoke control makes use of mechanical fans to produce airflows and pressure differences to control smoke movement. Describes one day of tests of the smoke control systems at the 6-storey VA hospital, San Diego, California.
Gives basic facts about indoor air pollution for homeowners. Lists common indoor air pollutants and guidelines for generally acceptable levels of selected air contaminants. Some suppliers of measurement equipment are mentioned.
Contains articles on rain penetration and moisture damage in residential construction, moisture sources in houses, control of surface and concealed condensation, and ventilation of houses. Illustrates the various types of condensation problems that may occur, explains the active processes involved in some of these problems and discusses in detail the principal factors surrounding these phenomena i.e. sources of moisture, choice of construction detail, and current ventilation practice.
The various meanings of ventilation efficiency are briefly summarised. The residual life time of a released tracer gas is chosen as the most meaningful and convenient basis for local efficiency measurements in large, occupied, mechanically ventilated buildings. Measurements were carried out in ten public swimming pool halls. Sulphur hexafluoride tracer gas was released from a 20 ml syringe at various locations around the pool hall and the integrated concentration with respect to time was measured at the exhaust air duct. This was extrapolated to infinite time using the measured decay rate.
Air infiltration flows into different zones of a building can be measured with the constant concentration technique by injecting a metered amount of tracer gas t o hold the concentration of the gas constant. The control and estimation algorithm used to calculate the injection rate is designed using classical transform and optimal estimation methods. The ability of the control algorithm to keep the concentration constant and to accurately measure time varying infiltration flows is demonstrated using digital computer simulations and laboratory experiments.
This paper discusses the indoor formaldehyde levels in two groups of houses. With the exception of the heating and ventilation systems, the house construction, formaldehyde sources and occupancy were similar for the two groups, One group (A) used electric baseboard convective heaters for space heating and semi-ducted heat recovery ventilators (HRV) for supplying outdoor air and exhausting indoor air , The second group (B) had electric forced-air furnaces with a ducted air supply to every room, Outdoor air was drawn in via a connection to the return air ductwork.
The R-2000 Super Energy-Efficient Home Program is a cooperative industry/government initiative sponsored by Energy, Mines and Resources Canada (EMR) and delivered by the Canadian Home Builders Association. The program supports building industry development, training of builders and the construction of energy-efficient houses incorporating high levels of insulation, a well sealed air barrier and mechanical ventilati on systems with heat recovery. In 1983, with assistance from the Buildings Energy Conservation Sub-Committee (B.E.C.S.
The multiple tracer gas technique developed at UMIST has been applied to the measurement of roof-space ventilation rates and house to roof-space air movement, for various types and combinations of roof-space ventilation. It has been shown that ridge tile ventilators, whilst increasing roofspace ventilation rates at low wind speeds, also significantly increase house to roof-space airflows over the whole range of wind speeds. This has implications not only in terms of energy wastage, but, more significantly , in terms of increased moisture rates to the roof-space.
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