Provides basis for planning and installing plant for maintaining indoor climate based on previous draft which is based on earlier Danish Standard. Refers to several salient design criteria including leakage factors at given test pressure, maintenance of climate parameters, air quality, anticipated energy consumption. Gives example table for requirements of building in terms of m2/person depending on application. States example tolerances of air flows.
The author examines the influence on thermal comfort of the air flow inside wall air spaces, on the assumption of a stabilized periodical condition. In these particular conditions an increase of the circulating thermal flow always involves a lowering of the reduction factor, and this increase is greater thelower are the thermal inertia characteristics of the outer wall. Displacement values are found to be mainly influenced by the physical characteristics of the outer wall.
Notes that many air conditioning and industrial installations function inefficiently since too little attention is paid to air movement in a room. Compares effect of inlet and exhaust air devices. Considers reduced ventilation need if pollution can be eliminated or reduced. States that ventilation efficiency is an indication of how efficiently the air is used in the occupation zone and that the air supply to a zone determines ventilation efficiency. Illustrates various forms of ventilation.
Indicates that 35-70% of a building's annual energy consumption is used by ventilation plant. Notes difficulty in determining which energy saving measures are most profitable but states that restricting fresh air supply tothat required is one measure that has not been considered and that most systems are designed for maximum capacity without facilities for varying load according to conditions. Describes plant which uses CO2-controlled ventilation in a sports hall. Illustrates circadian changes.
Discusses principle that the position of supply air devices has a considerable influence on the ventilation efficiency that can be achieved. Considers factors affecting ventilation efficiency and different ventilation models. Illustrates different air supply systems.
Describes method which permits long term tracer gas measurements in several separate rooms simultaneously. The method employs a fully automated constant concentration system developed at the laboratory for building physics at the Swedish Institute for Materials Testing. Describes measurement principles andpractice.
Over 200 reports of health hazard evaluations are available of sealed, air-conditioned buildings, requested by occupants who believe their buildings to be hazardous to their health. Describes a computer based building information system developed to extract relevant information about internal environmental measures, disease characteristics and history of occupants, as well as relevant features of the architecture and ventilation conditions of buildings.
Data collected in a LBL study on ventilation in four public buildings includes sensory evaluations of indoor environment and of physical and chemical properties of indoor air. Analyzes database to establish how the indoor odour acceptability criterion (acceptability by 80% of individuals entering theoccupied space) depends on other qualities of the indoor air. Finds that the staleness freshness rating correlates to the odour acceptability better than odour intensity alone. At low concentrations formaldehyde or aldehydes increase odour intensity but also improve odour acceptability.
Compares measured hourly data on indoor humidity with data obtained by calculative values for NBS Houston test houses and for the high mass test building in an environmental chamber. Measured values are usually very different from the calculated values if no considerations are given to moisture absorption and desorption phenomena that take place at the interior surfaces. Introduces the Tsuchiya model that permits the evaluation of room surface moisture absorption capability.
Looks at ventilation requirements for both odour and physical acceptability and pays particular attention to the differences between smoking and non smoking occupancy in an environmental chamber. Results imply that under non smoking conditions and with moderate humidity, between 5 and 10 cfm of fresh air per occupant should satisfy 75% of visitors, but that under smoking conditions, many times as much fresh air is needed for both odour acceptability and compliance with customary criteria values for smoke.
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