This study was performed to determine the effects of soil and building materials on indoor radon concentration. Short-term measurements were made in the underground soil of a building along with the radon emanation rates from the phosphogypsum board used as the interior wall. The radon measurements in the soil were 9,213 Bq/m3 in the B3 level, and 3,765 Bq/m3 in the B4 level. Soil radon concentration in the B4 level was 2.4 times higher than in the B3 level. Indoor radon measurements in 50 different locations in the underground of the building, averaged from 144.3 Bq/m3 (B1), 177.0 Bq/m3 (B2), and 189.2 Bq/m3 (B3) to a high of 210.1 Bq/m3 (B4). Indoor radon concentration was increased from the lower level to the upper level. The radon emanation rates from phosphogypsum were 4,234.1 mBq/m2/h and, 450.4 mBq/kg/h. The measurement results indicated that the phosphogypsum board used as building materials as well as the soil could affect the indoor radon concentration.

In this study, the homogeneity and stability of standard samples for proficiency testing in indoor air quality within the country (formaldehyde, benzene, toluene, ethylbenzene, p-xylene, styrene, TVOC) were evaluated. The procedures and statistical analysis methods applied in ISO/IEC 13528 (2009) and KS A ISO Guide 35 (2005) were applied as evaluation methods. The homogeneity evaluation was a statistical analysis of repeated measurements of each of the 11 ports and between the 11 ports concentration data. As a result, the coefficient of variation (CV) was within the range of 1.9%~5.9%. The difference between the ports was found to be insignificant and met the statistical standard specified in KS Q ISO 13528. The stability evaluation was assessed by the change in concentration over the long-term stability of the standard samples stored for 90 days. The coefficient of variation (CV), which was within the range of 2.6%~9.0%, exhibited changes in the concentration of the long-term stored standard samples. However, the results satisfy the statistical standard specified in KS A ISO Guide 35. Overall, there is no significant difference between the homogeneity of the standard samples by the port and the stability of the long-term stored samples. Therefore, it is considered to be an appropriate method to supply standard samples in an indoor air quality proficiency test.

Developing proper reduction strategies of indoor radon which have been an important issue in Korea requires proper information on source characteristics a phosphate gypsum board which is a common building material used for inter-wall thermal protection in Korea could be a major source of indoor radon level. This study evaluated the correlation between indoor radon concentration and the attribution of gypsum board content in building materials. In this study we valuated indoor/outdoor radon from 58 facilities selected based on the information availability of gypsum content in the building material across 8 different cities in Korea. Our results showed that indoor radon concentrations were 2 to 3 times higher than outdoor but those results were not significantly attributed from gypsum contents in the building material. Indeed, phosphate content in gypsum board did not significantly play a role in indoor radon level variations. It is concluded that physical environmental condition such as temperature, relative humidity, radon exhalation rate out of each building materials, as well as pathway from external sources (e.g., soil) needs to be identified to develop indoor radon reduction strategies.

Indoor air quality can be affected by indoor sources, ventilation, outdoor levels, and removal. Various indoor and outdoor combustion sources make nitrogen dioxide(NO2), which is a by-product of high temperature fossil fuel combustion. Especially, the presence of gas ranges and smoking have been identified as two of the major factors contributing to indoor NO2 exposures. In this study, the relative efficiencies for NO2 removal by a large number of materials are presented. This work has demonstrated that reactions with indoor surfaces represents a significant sink for NO2, and that these reactions currently are effecting a considerable degree of control over indoor NO2 levels. It seems that this control could be enhanced by judicious selection of furnishings and construction materials. Improved understanding of that rates and mechanisms of the removal process will permit optimization of the process for indoor air quality improvement.

In this study, the paint, which has very close relationship to the of indoor air quality, was examined for the air pollution leveling test, and using the various passive sampler, the test was evaluated on the regard of TWA(Time Weighted Average). This study is to examine how the air pollution levels differ between the regular paint that is used for public and the new developed environment friendly paint. The consecutive experiments were performed in the small chamber test to investigate the VOCs and formaldehyde, ammonia emissions and characteristics from paint which are commonly used as the complete material of building. In conclustion, the natural paint showed the highest emission of VOCs among the selected paints, and water paint showed the highest contents of ammonia. Formaldehyde showed N.D(Not Detected) in most of tests and found a small amount in vinyl paint however, it was not as bad as to fail the certify level of building materials. It is recommended to constantly develop the chamber system and it will be very much possible to be used for the estimation of indoor air pollutants from the various paints and other complete materials.

디벤바키아, 벤자민고무나무, 그리고 아레카야자를 이용하여 화분의 지피물질에 따른 포름알데히드 제거 효율을 측정하였다. 화분 지피물질로는 가는 자갈, 모래, 수태, 셀라지넬라를 이용하였다. 셀라지넬라 지피가 포름알데히드 제거 효율이 가장 높았고, 모래 지피가 가장 낮았다. 가스 처리 2시간 후 셀라지넬라 지피의 포름알데히드 제거율은 모래에 비해 25% 높게 나타났다. 지피 방법과는 상관없이 식물 종류별로 포름알데히드 제거율을 비교하면 디벤바키아가 가장 우수하였고 그 다음이 벤자민고무나무, 아레카야자 순이었다. 지피 방법별 초기 가스 농도의 절반에 도달하는 T50%은 자갈, 모래, 수태 그리고 셀라지넬라가 각각 88, 118, 81, 53(분)이었다. 이러한 결과는 지피물질에 따라 오염된 공기가 근권부에 도달하는 양이 다르기 때문으로 보인다. 결과적으로 지피물질별 포름알데히드 제거 효율은 셀라지넬라가 가장 우수하였다.