Looks at some studies that have been done to see if the retrofits have actually changed indoor air quality and changed pollutant concentrations. The first study (1981) of 18 homes in Washington state used the house doctor technique. The second study was of two homes in Medford, Oregon and one in Cranbury, New Jersey, all monitored for two weeks. The third study was of two identical houses in Rockville, Maryland, monitored over a year. One of them was retrofitted using the house doctor technique, as a result of which air leakage dropped by 40%. A fourth study of fifty houses is mentioned.
Discusses the physical, chemical and biological effects that moisture can have on indoor air pollutants such as formaldehyde, radon, aerosol particles, minerals from concrete, ozone, nitrogen dioxide, polyurethane, microbes and organic vapours.
Introductory talk on the indoor air quality problem. Compares risk of radon pollution in houses to the risks of smoking tobacco, and gives a definition of levels of concern. Mentions filtering of indoor air by means of an air-to-air heat exchanger, the interaction between ventilation and sources, e.g. unvented combustion heaters and carbon dioxide emissions; measurements of nitrogen dioxide are compared, and formaldehyde concentrations in 28 different commercial buildings.
Commercial buildings require mechanical ventilating systems, the specifications for which are included in the building codes. These codes specify the amount of outdoor air to be supplied per person for designed occupancy conditions. Many buildings such as retail establishments operate much of the time at occupancy loads well below the design. Thus, they are generally over ventilated and waste energy when operated according to the codes. A control system based on measurement of the carbon dioxide generated by the occupants was tested in a small bank in Pasco, Washington.
Air-to-air heat exchangers were evaluated as a method of maintaining indoor contaminant concentration levels below acceptable levels. A mathematical simulation of air infiltration and indoor contaminant generation was used todetermine the distribution of contaminant concentrations at various average intervals including hourly and yearly. Both spot generation such as from unvented combustion, and diffuse sources, such as from materials, were considered for four contaminants, nitrogen dioxide, carbon monoxide, carbon dioxide and formaldehyde.
The results of exposure chamber and field validation tests of NO2 diffusion tubes are reported. In an exposure chamber about 50 test runs at various relative humidities were performed. The field validation consisted of comparisons between tubes and a chemiluminescence monitor in 9 homes during several days in kitchen, living room, bedroom and outdoors. The results indicate a dependency on relative humidity, while the often quoted accuracy of 10% for the diffusion tubes might be too optimistic for the use of the tubes in homes.
Reports results of studies of concentrations of carbon monoxide, nitrogen dioxide, respirable suspended particulate matter and volatile hydrocarbons in houses in the Netherlands. Carbon monoxide and nitrogen dioxide were studied in about 300 homes in Arnhem and Enschede in October-December 1980. Respirable suspended particulate matter, nitrogen dioxide and volatile hydrocarbons were measured in 175 houses in Ede in winter 1981-82. Indoor air pollution was often much higher than the common outdoor levels. In several houses existing or proposed standards for ambient air were exceeded.
Describes the influence of gas geisers on carbon monoxide and nitrogen dioxide production in 254 houses in the Netherlands. It was shown that burner type and maintenance system were the main factors influencing the carbon monoxide levels in the flue gases. The nitrogen dioxide concentration in the kitchen was greatly influenced by the presence of a flue for the geiser and by use of a cooker hood. Associations were also found with type of space heating, use of shower and socioeconomic status of the occupants.
Discusses sources of nitrogen dioxide in indoor air in houses in the Netherlands. Measurements were made in a random sample of about 300 houses with a geiser in Enschede and Arnhem. A second sample of 326 houses in Ede were measured a year later. The Dutch outdoor standard for concentrations of nitrogen dioxide was regularly exceeded indoors.