As radon is a naturally occurring radioactive gas that can cause lung cancer and is classified as a Group 1 carcinogen, it is essential for the public to be aware of what radon is, and how to manage radon. Therefore, general information on radon, as well as its health risks, measurement methods, mitigation methods and suggestions for its management are addressed in this article. Over the last one to two decades, a number of wide-ranging studies on radon measurement and mitigation have been conducted in Korea, and the results of each study are comparable to the research achievements of other developed countries. For this reason, it is time to systematically establish a well-made Korean radon management organization.

The purpose of this study was to evaluate the concentration of airborne particulate matter and heavy metals in the houses of the respiratory tract disease patients and a control group of residents in the city of Gwangyang. The particulate matter was measured using a mini-volume air sampler and then weighed three times using a micro balance to calculate the weighted average value. The heavy metals in the particulate matter were extracted using a hot plate and analyzed using an inductively coupled plasma/mass spectrometer. The average concentration of particulate matter in the outdoor air (34.478 μm/m3) was higher than that in the indoor air (16.794 μm/m3), showing a statistically significant difference (p<0.001). The average concentration of copper, manganese and chromium in the indoor and outdoor air were higher in the houses of those in the study group than those of the control group. In addition, there was a generally high correlation between particulate matter in the outdoor air and heavy metals in the indoor and outdoor air concentration (p<0.05).

Seasonal emission characteristics of odors and methane were investigated throughout the period of 17 months in which the emission status of odors and methane from soil cover layers in a sanitary landfill was measured. Complex odor emitted from soil cover layers fluctuated largely at the range of 7~20,800 OU (Odor Unit) in odor dilution ratio, and the median and average values were 2,080 and 4,203 OU, respectively. The intensity of complex odor showed higher values in the spring (5,663 ± 4,033 OU) and winter (6,056 ± 8,372 OU) than in the summer (1,698 ± 3,676 OU) and fall (1,761 ± 451 OU). Based on average concentrations, the compounds with high contribution values for the sum of the odor quotient (SOQ) were hydrogen sulfide (46.1%), methyl mercaptan (26.4%), and dimethyl sulfide (16.8%). This result shows that sulfur compounds were the main odor-causing compounds in the target landfill. The flux of complex odor was 0.17~70.36 OU·m−2·min−1 (Median 0.47, Average 5.40), and the flux of hydrogen sulfide was 0~114.70 μg·m−2·min−1 (Median 0.13, Average 5.91). The methane flux was 0.59~312.70 mg-CH4·m−2·min−1 (Median 25.61, Average 47.99). The methane concentrations emitted at the soil cover layers showed the highest values of 1.0~62.5% (Median 33.0, Average 21.1) in the spring, and the lowest values of 0.1~11.7% (Median 2.3, Average 3.7) in the winter. The methane concentrations in the summer and fall were similar with the average of 17.9% (range of 0.2-44.2%) and 12.5% (range of 2.2-42.5%), respectively. The emission data of odors and methane from soil cover layers can be utilized to establish management policy and apply mitigation technologies for the control of odor and greenhouse gases emitted in landfills.

This study aims to analyze the effects of 4 directions of wind, wind speed, year of construction of slate roofs, installation area and other factors on the concentration and size distribution of airborne fiber particles in farmhouses with a slate roof containing asbestos. Airborne fiber particle samples were collected from the air in six houses with a slate roof containing asbestos using a high flow rate pump (10 L/min) for 2 hours, three times a day with a different condition, 72 times in total. The airborne fiber particle concentrations were measured using a phase contrast microscope, and the size of fiber particles of 72 samples in total was estimated using the mean value of those in each sample measured at 100 with a field of view. The total average concentration of fiber particles collected from in the air in four directions of the targeted farmhouses was 2.83 fiber/L, and its maximum concentration was 5.75 fiber/L, which means that among all samples there was no place that exceeded 10 fiber/L, a recommended indoor air quality standard. The average size of the fiber particles was 11.55 μm, and the maximum size was 40 μm. A multiple regression analysis of factors affecting the concentration and size of fiber particles in the air collected from the farmhouses with a slate roof containing asbestos found that the closer to the main wind direction (p<0.001) and the faster the average wind speed (p<0.05), the fiber particles concentration became significantly higher. In this case, the coefficient of determination was 52.8%. It was also found that the wider the total area of the slate roof (p<0.001) and the slower the average wind speed (p<0.05), the longer the fiber particles; the coefficient of determination for this finding was 19.6%. The concentration of fiber particles in the air of farmhouses with a slate roof appeared to be the highest under the main wind direction, and became significantly higher as the wind speed became faster. This proved that fiber particles were leaked from the slate roof. The size of the fiber particles became significantly longer as the area of the slate roof became wider and the wind speed became slower.

This study investigated Extremely Low Frequency-Magnetic Fields (ELF-MF) exposure levels among housewives for a 24-Hour activity pattern to identify related factors for the exposures. To achieve the objective of the study, we surveyed ELF-MF levels using EMDEX II in a living environment from January to December 2016. We also made subjects write a Daily Activity Pattern in order to identify durations for staying and related information in the environment of exposures. Subjects showed that they spent the longest time in sleep and at home, at 487.5 minutes (KOSIS: 479.0 minutes) and 472.1 minutes (KOSIS: 428.0 minutes), respectively. Furthermore, the 24- hour time-weighted average (TWA) of 54 housewives was 1.24 ± 3.48 mG (GM: 0.52 mG). The ELF-MF exposure levels for all Multiuse Facilities were far below the recommended standards of EMF Guideline Korea and ICNIRP. Thus, these results will provide useful data for the determination of ELF-MF management and reduction methods in living environments.

The purpose of this study was to characterize the concentration of and evaluate the pollution level of indoor air pollutants among the public-use facilities located in Seoul that are mainly used by medically sensitive users. The data used in this study were analyzed based on the supervision data provided by Seoul Metropolitan Government Research Institute of Public Health and the Environment. There were 399 nursery schools, 188 medical facilities, 42 elderly care facilities and 96 postnatal care centers. The indoor air pollutants to be investigated were analyzed for PM10, CO2, HCHO, TAB and CO. Through the analysis, it was found that among the surveyed pollutants, TAB levels exceeded the criteria most often, in 54 facilities. Among the surveyed facilities, nursery schools exceeded the criteria most often, in 49 facilities. There was a statistically significant difference between the pollutants in each facility (p<05). However, considering the characteristics of the data used in this study, additional factors should be investigated for factors affecting the concentration of each indoor air pollutant for a more rational evaluation.

This study measured concentrations of formaldehyde, a pollutant in the indoor air in three departments, before and after the renovation of a medical facility used by the general public, and conducted a health survey on workers' subjective symptoms. The average concentration of formaldehyde was 25.8 ± 8.7 μg/m3 before the renovation and 47.3 ± 6.7 μg/m3 after the renovation. The concentration was increased; however, it did not exceed the maintenance standard set by the law. Measured concentration was high both before and after the renovation in the office, and the biggest difference was shown in the concentration change. For eight symptoms including dry throat, there were more workers who expressed the symptoms after the renovation than those who expressed them before the renovation. Factors that influenced subjective symptoms were the effects before and after the renovation. Even when formaldehyde does not exceed the maintenance standard set by the law, detailed and systematic management is required and adequate health effect evaluation or education is necessary, considering the characteristics of medical facilities.

This study was carried out considering that activated carbon physically adsorbs radon. Among the air cleaners equipped with activated carbon filter, eight air cleaners sold in Korea were selected and the radon reduction rate experiment was conducted. The instrument used an ionization chamber type instrument with a sensitivity of 3 CPM. The experiment was carried out by excluding the natural rate of reduction of radon in order to accurately grasp the radon reduction rate of activated carbon filter. Of the eight air purifiers, only three showed a reduction rate of more than 30%, while the remaining five air purifiers showed a reduction rate of less than 20%. This does not seem to be much different from the natural reduction rate. In addition, since it is not adsorbed by radon alone due to the nature of activated carbon, it is expected that the reduction rate will be lower in a real life environment.

Due to economic feasibility and recycling policy of wastes, various types of residues have been studied particularly for high valued materials, such as gas adsorbents. In this study, the preparation of an adsorbent using the waste from coffee manufacturing process was attempted, and the removal efficiencies the odor and VOCs with acetaldehyde were quantitatively evaluated. The obtained coffee adsorbent had a specific surface area ranging from 400~1024 m2/g, the adsorption amount at the largest specific surface area was about 92.6 mg/g for acetaldehyde. The adsorption time by the characteristics of the adsorbents, such as pore, pore volume and the amount of adsorbent was also measured. This was to determine whether or not coffee adsorbents have any performance as adsorbent.

The purpose of this study was to investigate the current status of odor and to examine the application method of the odor emission standard in a restaurant environment. The complex odor dilution concentrations (“times”) and odor compounds were measured in 8 restaurants. The highest complex odor dilution times were 966 in outlets and 97 in site boundaries of C restaurants. The average complex odor dilution times were 632 in outlets and 29 in site boundaries, which exceeded the allowable odor discharge standard of residential areas. Eighteen of the 22 specified offensive odor substances were detected. Aldehyde-type substances showed high concentrations, and the highest concentration of ethanol was detected in addition to the designated odorous substances. Dichloromethane, benzene, and phenol, which are harmful air pollutants, were also detected. The odorant concentrations of restaurants were found to exceed the odor standard threshold in A, B, and F restaurants. Upon review of the Japanese-style odor index respective to restaurant odor, it is difficult to apply an equivalent emission allowance standard as the permissible emission standard of the workplace. It is necessary to regulate emission standards by different emission standards. In the future, it will be necessary to determine how to measure the odor index and how to apply the odor emission standard to everyday facilities, such as restaurants, grocery stores, etc.

Odor emission factors (OEFs) are important parameters in characterizing odor sources, understanding emission patterns, designing abatement facilities, and providing appropriate control methods. In this study, OEFs for complex odor from grit removal chambers in publicly-owned wastewater treatment plants were determined, and the major operating conditions affecting the emission factors were investigated. In the main study site of “S” wastewater treatment plant, the averaged OEFs from the grit chamber were found to be 466.2, 162.6, and 54.7 OU/m2/min in summer, spring, and winter, respectively. OEFs from two other grit chambers in different wastewater plants were independently measured for comparison, and the values were in the same range as the OEF from S-site at a 95% confidence level. Nevertheless, the OEFs could differ depending on the types of wastewater and the sizes of wastewater treatment plants. Using the multi-variable linear regression method, correlations between OEFs and operating conditions, i.e. activities, from grit chambers were statistically analyzed. The analyses showed that operating conditions, including total suspended solids, water temperature, and temperature difference between water and air, were the most significant parameters affecting the OEF. A linear equation using these three parameters was proposed to estimate the OEF, and can be used to predict an OEF for another grit chamber, without odor measurement.

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.

The purpose of this study is to investigate the effects of oxides (caryophyllene oxide, eucalyptol and linalool oxide), one of the major ingredients of essential oils, on odor intensity, electroencephalography (EEG) response and emotional response. The subjects were women in their twenties. Inhalation concentrations of oxides were varied from 0.01 to 10%, and EEGs were collected by Quantitative EEG. The odor intensity and average preference index (API) of the oxides were ranked in the order of eucalyptol > linalool oxide > caryophyllene oxide. Eucalyptol is a refreshing and pleasant substance that activates the brain (activation of β and γ waves and spectral edge frequencies (SEF50 and SEF90)). Linalool oxide has a calm and soft substance (activation of θ, inactivation of α, β, and γ waves) at a low concentration (<0.1%), and a fresh smell at high concentration (inactivation β and activation of θ and γ). Caryophyllene oxides were evaluated as a substance that is comfortable, soft, calm and sedating, which deactivates the brain (activation of α, inactivation of β and γ). Oxide materials showed a positive correlation between the odor intensity and the SEFs. Each of the oxides showed unique characteristics in the areas of odor intensity, emotional response, API, and EEG. These results give us a better understanding of the properties of the pure materials that make up a fragrance, and provide useful information for the manufacture of fragrance products or aroma oil blends with enhanced specific functions.