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Interior Alaska has indoor air quality issues similar to other far northern communities associated with long cold winters and reduced ventilation rates. Moreover, geological features in the hills around Fairbanks, Alaska increase the likelihood of elevated radon levels. Over thirty percent of the tested homes in the hills around Fairbanks had radon levels > 4 pCi/L compared with a nationwide average of 7%. Active sub-slab depressurization systems tested were very effective in reducing indoor radon concentrations (average reduction of over 90% for 8 homes).

An intervention study was carried out in eleven elementary schools in Trondheim, Norway. Three schools with poor ventilation standard, four schools with carpets, and four reference schools participated. Carpets were replaced by vinyl flooring and the poor ventilation systems were upgraded. Altogether 1100 children aged twelve to thirteen years and 400 teachers were all included in the study. The baseline registration of health related symptoms was performed during January/February 1997. The questionnaires were repeated, after the interventions, in February 1998 and 1999.

Two nation-wide indoor radon surveys have been conducted in Japan. There was a significant difference between the two surveys. The first survey covered over 7000 houses using Karlsruhe passive radon detectors developed in Germany. The first survey provided relatively higher radon concentrations than expected though there are many well-ventilated wooden houses in Japan. The arithmetic mean was estimated to be 20.8 Bq m-3. In the second survey, on the other hand, it was 15.5 Bq m-3.

Indoor exposure to particles of outdoor origin constitutes an important exposure pathway. We conducted an intensive set of indoor particle measurements in an unoccupied house under differing operating conditions. Real-time measurements were conducted both indoors and outdoors, including PM2.5 nitrate, sulfate, and carbon. Because the time-scale of the fluctuations in outdoor particle concentrations and meteorological conditions are often similar to the time constant for building air exchange, a steady state concentration may never be reached.

The Indoor Air Quality Committee of the Boston Society of Architects was invited to evaluate a large brick school building erected in 1963 to serve 1600 students. The investigation included a written questionnaire, evaluation of air using the ASTM E981 (modified) bioassay, fungal and bacterial testing, real time monitoring of carbon dioxide, carbon monoxide, respirable particulate, total volatile organic compounds, relative humidity and temperature. The survey and testing enumerated many potential causes for poor IAQ.

A study of 120 randomly selected classrooms in 30 schools in central and south Texas, USA was conducted to begin assembling baseline information on the condition of indoor air in Texas elementary schools. Part I of the study consisted of questionnaires sent to all teachers and staff in the schools to obtain information about the use of their rooms, room contents and their perceptions of its indoor air quality. Part II consisted of walkthroughs in each school and the 120 classrooms to obtain information on the building design, HVAC system and condition of the space/building.

The Texas Elementary School Indoor Air Study (TESIAS) involved several phases, including single-day continuous monitoring of carbon dioxide (CO2) in 120 randomly selected classrooms in two school districts. The median time-averaged and peak CO CO2 concentrations were 1,286 ppm and 2,062 ppm, respectively. The time-averaged CO2 concentration exceeded 1,000 ppm in 66% of the classrooms. The peak CO2 concentration exceeded 1,000 ppm in 88% of the classrooms and 3,000 ppm in 21% of the classrooms.

A research program has been initiated to focus on obtaining quantitative data in existing elementary schools through a longitudinal study with controls, interventions, and cross-sectional components. The overall objective of this program is to quantify the effects of simultaneous control of indoor exposures (i.e., thermal, indoor air quality or IAQ, lighting, and acoustics) on specific measures of human response, student and teacher performance, and productivity. The pilot study is being conducted in six elementary schools in Montgomery County Maryland.

Construction in healthcare facilities is a major risk for airborne agents infecting immune compromised patients. Standard air quality analysis has included air sampling for airborne fungi. These culture data require weeks for transport, incubation and identification. During a demolition and construction of a new medical facility an infection control risk assessment(ICRA) determined pre-construction precautions and surveillance methods. The surveillance utilized real time air particle analysis and culture methods to determine relevant indicators of potential hazards.

Several studies have shown that supply air filters in office buildings, schools etc. occasionally get wet due to weather impacts. The aim of this study was to investigate whether performance characteristics, such as pressure drop across the filter and filtration efficiency, change when two different kinds of air filters become soaked and dried. The filters used, were a fiberglass bag filter and a plastic fiber bag filter, each of filter class F7. The study showed that the filter getting wet did not affect the shape of the dried filter material of plastic fibers.