• 한국환경과학회지
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• 제7권3호
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• pp.375-382
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• 1998

우리나라 서해안에 위치한 서천지방 연안에 10m기상 관측탑을 설치하여 1년동안 관측한 바람자료를 사용하여 지상풍의 기초 통계량, 정상도 및 월별 정규성 검정을 조사하였다. 해륙풍과 같은 국지순환의 영향으로 8훨과 9월에 조차 북풍계열이 나타났다. 두 바람성분간의 상관계수는 6월과 9월사이, 10월과 4월사이 기간동안에 각각 양((+)과 음(-)의 값으로 나타났다. 바람의 정상도는 겨울철에 높게.여름철에 낮게 나타났다. 샘플링 시간이 증가함에 따라 S값의 modal이 감소하고 최대 발생빈도값이 5값의 낮은 영역으로의 이동이 뚜렷하게 나타났다. 패도와 초가 첨도에 기초한 월별 정규성 검정으걸 부터 바람의 동서성분은 봄철에. 남북성분은 늦여름과 초가을에 각각 정규분포를 가짐을 알 수 있었다.

• 한국산업보건학회지
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• 제6권1호
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• pp.97-108
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• 1996

A new type of passive samplers were designed and produced by authors. After evaluating the quality of activated carbon by measuring recovery rate of organic vapors and steadiness of sampling rate, activated carbon with 30 - 35 mesh produced by Company S in Korea was selected. In each passive sampler, an amount of 400 mg of the activated carbon was filled in 25-mm cassette and covered by fixed screen (or wire screen with 100 mesh). In addition to the fixed screen, a wind screen (or wire screen with 300 mesh) was also attached at outer face. The sampling rate of the new Korean passive samplers was estimated Conclusions obtained in the study are as follows. 1. Sampling rates of the newly developed Korean passive samplers were affected by sampling time. For n-hexane, sampling rates of 15- and 60-minute samples were 70.92 and 37.45 ml/min, respectively. Sampling rate of both 200- and 450-minute samples was 25.96 ml/min. It is concluded that, when passive samplers are used for measuring organic vapors, samples be collected longer than 60 minutes. 2. Sampling rate of the passive samplers was also affected by airborne concentration of organic vapors. Lower sampling rates were determined at level of 1/2 threshold limit values (TLVs) recommended by the American Conference of Governmental Industrial Hygienists (ACGIH). It is recommended that sampling rate of the passive samplers be obtained at site by measuring concentrations using both the NIOSH Method and passive samplers simultaneously. 3. When the passive samplers, which collected organic vapors, were exposed to clean air for five hours, there was no significant loss of organic vapors due to reverse diffusion. 4. When samples were stored at room temperature ($21.8{\pm}0.7^{\circ}C$) and refrigerator ($3.8{\pm}0.7^{\circ}C$), there was no significant difference in the accuracy of results. For trichloroethylene and n-hexane, accuracies were within 25 % at both temperatures until seven days. However, poor accuracy exceeding 25 % was indicated in toluene from the first day. It is recommended that samples be stored at freezing temperature below $0^{\circ}C$. 5. Sampling efficiency was significantly affected by direction of the passive samplers. Results of samplers facing wind and down, respectively, were compared. Lower amount of organic vapors were collected when the sampler was oriented down. It is recommended that, when air velocity is low in plants, the passive samplers be oriented to the wind. However, when air velocity is high, the passive samplers be oriented down.