Reviews the present state of knowledge of indoor pollutant concentrations, their time dependence and their relationship with indoor sources, energy conserving measures and indoor activity patterns. Pollutants of primary concern are organic compounds, respirable suspended particulates, nitrogen dioxide and allergens. Assesses knowledge of carbon monoxide, formaldehyde, radon and infectious agents. Reviews typical concentrations of carbon monoxide, asbestos, mineral fibres, ozone and sulphur dioxide in residences. Concludes that a systematic assessment of indoor air quality is warranted.
Characterizes indoor contaminants as two continua - mass stressors and energy stressors. Describes the rates of generation and transportation of contaminants in terms of 4 sources (outdoor air, building materials, occupants and indoor processes) in 4 environmental zones. Reviews information on contaminant generation and discusses factors that affect these rates, including temperature, moisture content, acidity, room air distribution and occupant proximity. Concludes that sufficient information is available for new control strategies to be used to provide acceptable indoor air quality.
Examines what adequate ventilation rates are needed to control indoor levels of formaldehyde. Concludes that the ventilation rate procedure of ASHRAE Standard 62-1981 "Ventilation for Acceptable Indoor Air Quality" offers protection from expected formaldehyde outgassing rates. Since formaldehyde outgassing decreases with time, increased ventilation during the first 2-3 years of the life of a structure is desirable. More data is needed to establish what the outgassing rates are and how they vary with temperature.
States that many health complaints attributed to tight buildings (tight building syndrome) may be alleviated by slightly lowering the thermostat. Discusses the ISO draft proposal DP7730 which defines comfort limits in buildings for occupants according to several comfort parameters.
A rational method is presented to determine the locations within a building where the highest average concentrations of contaminants may occur. Using this procedure, the number of sampling points necessary for indoor air quality (IAQ) evaluation of a building is reduced to a minimum. Thus the time and cost necessary for building evaluation and analysis can be decreased. Experimental measurements made in a research house are presented to validate the method.
A comprehensive theoretical framework is presented, based on the use of moments of concentration histories ie multiplying concentration readings by time of reading and then integrating with regard to time. The concept can be used to characterize either the diffusion of the supplied air or a contaminant released within the room. Results are presentd from about 50 measurements demonstrating the usefulness and practical applicability of the approach for assessing air quality in ventilated buildings. Different experimental procedures have been explored and are discussed.
Indoor air quality is determined by the sources of the contaminants and the methods used to control their concentrations. To predict the quality of air, algorithms are needed to model the rates of generation, transfer and removal of contamina
States that although the conditions for a comfortable climate are well known - especially temperature and air humidity - increased concern with energy conservation means it is important to discover what effect energy conserving measures have on the health,well-being and efficiency of people. Pressing questions are - how far can room temperature be lowered without affecting comfort and how is room air quality affected by a lower air change rate or a reduced fresh air supply. Summarises recommended room temperatures for various levels of activity.
Describes a mathematical model for the calculation of the expected values of radon and radon daughter concentrations in indoor air. Presupposes that it is possible to obtain or measure the parameters necessary for the calculation eg the radon emanation of the building material, the radon content of the soil air, and the leakage of air from the soil into the building. Research in these areas is in progress both in Sweden and abroad.
Despite having balanced mechanical ventilation, a large number of modern buildings in Sweden have unsatisfactory indoor climate. Problems include mould, irritation of the eyes, nose and throat, skin rashes, feelings of dryness, hoarseness andheadaches. To control ventilation according to requirements the right indicator variable must be selected and the system must permit the proper control in the occupied zones. Measurements of air pollutants were carried out outside and inside a mechanically ventilated office building.