Reducing the air change rate of a house increases the concentration of pollutants in the indoor air. These pollutants are identified and located within the residential structure. Air-to-air heat exchangers are suggested tocontrol ventilation, and the three basic types described.
Thirty residences were monitored for nitrogen dioxide, carbon monoxide, formaldehyde, respirable suspended particles, and air exchange rate for forty-one one-week periods using integrating samplers. The residences were located in the northwest a
Indoor air quality sampling strategies and analytical techniques have changed significantly in the past ten years. The changes reflect both the shifts in study objectives and the development of new forms of instrumentation. Toillustrate these trends, this paper describes early field techniques for measuring indoor air quality using a heavily instrumented mobile laboratory that is suitable for measuring one building intensively for up to four weeks.The style of measurement now is complemented by large field survey projects using passive samplers as the dominant instrumentation.
A discussion of different approaches to indoor air pollutant monitoring is presented. Indoor sampler design criteria are outlined. Grab samplers, personal samplers, passive and single-use devices, and in-situ measurement instruments are compared to novel, syringe/adsorbent tube samplers. These instruments provide automated, sequential, time-averaged collection of avariety of indoor pollutants, including hydrocarbon/halocarbon organic vapours, CO, CO2, HCOH, tobacco smoke, combustion and odorous mixtures, and particulate matter. In addition, the samplers can be used in infiltration studies.
As our understanding of human exposure to air pollutants improves, it is becoming increasingly evident that indoor environments play a critical role in determining exposures. However, it is not possible at the present time toestablish the relative contribution of indoor and outdoor sources to personal exposures, nor can the contribution of specific indoor emissions be quantified. To address these issues, a chamber experiment was initiated to measure particulate and organic emissions from important indoor sources.
The air infiltration associated with ventilation in buildings is recognized in ASHRAE Standard 62-1981, Ventilation for Acceptable Indoor Air Quality. In the light of recent trends toward increasingly tight housing, which limits air infiltration for ventilation, dependence on this source of outside air is onepoint that must be carefully considered in the Revised Standard. Other points to be considered are ventilation efficiency, necessary dilution of particulates and other pollutants, and how changes in humidity, air temperature and local heating may alter pollution levels in buildings.
Eleven countries are cooperating to establish guidelines for minimum ventilation rates which are sufficiently large to meet the demand for outdoor air in buildings without unnecessarily wasting energy. The most important pollutants have been identified as: carbon dioxide, tobacco smoke, formaldehyde, radon, moisture, body odour, organic vapours and gases, combustion products and particulates. To a certain degree some of thesesubstances can be used as indicators for acceptable air quality to establish minimum ventilation rates.
An investigation of the minimum fresh air supply per person required to prevent the occurrence of unacceptably offensive odour due to stale air in offices and similar buildings. The study was made under everyday conditions as far as possible, in different buildings, various size rooms, different densities of occupancy, with men or men and women, and with mechanical or natural ventilation.
The minimum fresh air requirements needed for perfect indoor air quality are being studied and these will form the basis of the Swiss Guidelines for Ventilation. An optimization between the need to reduce heat loss and fresh air requirements for health is the aim. Pollutants in indoor air, such as formaldehydes, radon, carbon dioxide, tobacco smoke, carbon monoxide, nitrogen dioxide and particulates, have to be considered.
Diffusion-type passive monitors were placed for a two-week period in each of 303 residences in the New Haven (Conn.) area during a 12 week sampling period January to April 1983. For each home NO2 levels were recorded outdoors, and in three ro
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