대학 실험실 장비 중 석면 함유 조사

함승헌 ( Seung Hon Ham ),김성호 ( Sung Ho Kim ),염종수 ( Jong Soo Yeom ),정진호 ( Jin Ho Chung ),이익모 ( Ik Mo Lee ),윤충식 ( Chung Sik Yoon ) 한국산업위생학회 2011 한국산업보건학회지 Vol.21 No.2

Objectives: The aim of this study is to survey for finding asbestos containing equipment at the laboratories using picture based questionnaire and polarized light microscopic analysis. Methods: This study was conducted from 2009 to 2010 at a university in Seoul. In 2009, picture based questionnaire was distributed to 100 laboratories during the regular laboratory air quality monitoring. In 2010, we emailed all professors of the same university who have laboratories to participate voluntarily this survey. For the laboratories consented to participate survey, picture based questionnaire was distributed and collected. Suspected asbestos containing material and apparatus were collected at the laboratories which replied they have suspected material and equipment. Collected samples were analyzed with polarized light microscope at the laboratory accredited by ministry of employment and labor in Korea. Results: Total of 18 out of 100 laboratories reported that they had suspected asbestos containing equipment in 2009. Twenty-three samples were collected and three samples (13%), one heating mantle and two pairs of insulation gloves, contained asbestos. Thirty four laboratories reported they had suspected asbestos containing material or equipment in 2010. Sixty samples were collected and four of them (6%), two pairs of insulation gloves, one packing rope in dry oven and, one pair of tongs, contained asbestos. All founded asbestos was chrysotile and the content of chrysotile was more than 90% for all equipment except heating mantle which has less than 1%. Conclusions: We confirmed that asbestos was still used at the laboratories though strict regulations on asbestos use in Korea. The method of picture based questionnaire invented in this study could be applied for asbestos survey to other research institute or university where there are many laboratories because of its simplicity and accessibility without huge man power, cost and time.

석면 분석방법에 대한 고찰

함승헌 ( Seung Hon Ham ),황성호 ( Sung Ho Hwang ),윤충식 ( Chung Sik Yoon ),박동욱 ( Dong Uk Park ) 한국산업보건학회 2009 한국산업보건학회지 Vol.19 No.3

서울대공원 코끼리 열차 특성에 따른 탑승자의 초극미세입자(Ultrafine Particles) 노출

주송이,황지희,함승헌,이기영,Joo, Song-Yi,Hwang, Ji-Hee,Ham, Seung-Hon,Lee, Ki-Young 한국환경보건학회 2012 한국환경보건학회지 Vol.38 No.5

Objectives: The objectives of this study were to measure passengers' exposure to ultrafine particles (UFP) and to determine effects of fuel, operating condition and position of seat. Method: UFP exposures in front and back seats of the Elephant vehicle in Seoul Grand Park were simultaneously measured by a condensation particle counter (P-Trak model 8525, TSI). The measurements were conducted 7 times with diesel-powered vehicle and 3 times with electricity vehicle in one day. The vehicle stopped at 3 locations along with 2.2 km of driving route. Results: UFP concentration in diesel-powered vehicle was significantly higher than electricity vehicle. At front seat of diesel-powered vehicle, average UFP exposure during stopping was significantly higher than during moving. When diesel-powered vehicle moved, UFP exposure in back seat was significantly higher than in front seat. Conclusions: Passengers in the diesel-powered Elephant vehicle could be exposed to high level of UFP. The UFP exposure was associated with operation condition and position of seat.

소방 공무원의 시간활동 양상과 직무에 따른 소음 노출 특성

이임규,강태선,함승헌,김정인,양영숙,윤충식,Lee, Lim-Kyu,Kang, Tae-Sun,Ham, Seung-Hon,Kim, Jung-In,Yang, Young-Suk,Yoon, Chung-Sik 한국환경보건학회 2011 한국환경보건학회지 Vol.37 No.2

Objectives: The purpose of this study is to evaluate the noise exposures of firefighters according to their time-dependent activity patterns. Methods: Personal exposure levels were measured for six days and nights using noise dosimeters; three days and nights for on-duty tasks, the other days and nights for off-duty activities. Results: The total amount of time spent in the workplace was 13,677 min (67%), outside areas 4,833 min (23%), in transit 1,002 min (5%), and other indoor area 807 min (4%) during a working period. However, during off-days they spent 10,858 min (76%) at home, 1,382 min (10%) outdoors, 1,225 min (9%) other indoors, and 493 min (3%) in transit. As a result of individual exposure levels, TWA did not exceed 90 dBA of the occupational exposure limit for the majority of the firefighters, whereas the levels of Lmax were 119 dBA, which were higher than the noise levels of firefighters in USA. Sometimes during dispatching the levels of Lpeak exceeded the ACGIH exposure standard (140 dBC). The Leq levels in transit were higher than the levels in home and other indoors even though the activity time is short. Conclusions: This paper characterized the noise exposure patterns of firefighters in Korea. We suggest that special noise sources, including sirens and speaker phones, should be readjusted to reduce noise exposure.

미술대학 조소작업 중 발생하는 분진 및 소음에 대한 노출평가

조현우,윤충식,함승헌,이임규,박지훈,박동진,정진호,염종수,서규진,Cho, Hyun-Woo,Yoon, Chung-Sik,Ham, Seung-Hon,Lee, Lim-Kyu,Park, Ji-Hoon,Park, Dong-Jin,Chung, Jin-Ho,Yeom, Jong-Soo,Seo, Kyu-Jin 한국환경보건학회 2011 한국환경보건학회지 Vol.37 No.4

Objectives: A great number of hazardous agents can be emitted from various types of art-creation in a fine arts college, but little data on exposure assessment has been published. A variety of processes encompassing toxic or non-toxic materials, tools, and components are involved in a sculptor work at a fine art college. The aim of this study was to assess exposure levels to particulates and noise during sculpture classes in a college of fine arts. Methods: Students in sculpture classes participated in this study. Mass, number, and surface area concentrations of particulates, noise level, temperature and relative humidity were monitored by both personal and area sampling during the tasks of metal, wood, and stone sculpting. Results: The number and surface concentration of particulates was the highest in the task of wood sculpting, followed by metal and stone work. The mass concentration of particulates was the highest in stone sculpting (personal GM 3.0 mg/$m^3$, GSD 3.0), followed by wood (personal GM 1.5 mg/$m^3$, GSD 1.8) and metal work (personal GM 0.95 mg/$m^3$, GSD 1.51) in that order. Occupational exposure limits (OEL) for particulates depends on the type of particulate. For wood dust, 86% (six subjects) of the personal samples and all area samples exceeded the Korean OEL for wood dust (1 mg/$m^3$), while 20% (two subjects) among stone sculpting students were exposed above the Korean OEL (10 mg/$m^3$). In contrast, metal sculpting did not exceed the OEL (5 mg/$m^3$). For noise level, metal sculpting students (Leq 95.1 dB(A) in the morning, 85.3 dB(A) in the afternoon) were exposed the most, followed by stone sculpting (88.3 dB(A)), and wood sculpting (84.8 dB(A)) in that order. Compared with the 90 dB(A) of the Korean OEL and 85 dB(A) of the American Conference of Governmental Industrial Hygienists' threshold limit value (ACGIH-TLV) for noise, 100% of the subjects (five subjects) and area samples during metal sculpting in the morning session exceeded both OELs, but only three subjects (60%) exceeded the ACGIH-TLV in the afternoon session. For stone sculpting, 50% (one subject) and 100% (two subjects) exceeded the Korean OEL and ACGIH-TLV, respectively, but the area sample did not exceed either OEL. During wood sculpting, two subjects (40%) exceeded ACGIH TLV. Conclusions: This work evaluated the sculptors' exposure to particulate matter and noise in fine art college, and revealed a poor working environment for the participating students. Effective measures should be supplemented by the administration of colleges.

화학물질 관리 연구-1. 산업안전보건법상 관리 화학물질의 특성과 노출기준 비교

박지훈 ( Ji Hoon Park ),함승헌 ( Seung Hon Ham ),김선주 ( Sun Ju Kim ),이권섭 ( Kwon Seob Lee ),하권철 ( Kwon Chul Ha ),박동욱 ( Dong Uk Park ),윤충식 ( Chung Sik Yoon ) 한국산업보건학회 2015 한국산업보건학회지 Vol.25 No.1

Objectives: This study aims to compare the physicochemical characteristics, toxicological data with Occupational Exposure Limits (OELs) of chemicals under the Occupational Safety and Health Act(OSHA) regulated by the Ministry of Employment and Labor of Korea. Methods: Information on chemicals which have OELs on physicochemical characteristics and toxicological data was collected using Material Safety Data Sheet(MSDS) from Korea Occupational Safety and Health Agency(KOSHA) and the Korea Information System for Chemical Safety Management(KISChem) in 2014. Statistical analyses including correlation and simple regression were performed to compare the OELs with chemical characteristics including molecular weight, boiling point, odor threshold, vapor pressure, vapor density, solubility and octanol-water partition coefficient(OWPC) and toxicological data such as median lethal dose(LD50) and median lethal concentration(LC50). Results: A total of 656 chemicals have OELs under OSHA in Korea. The numbers of chemicals which have eight-hour time weighted average(TWA) and short term exposure limits(STEL) are 618 and 190, respectively. TWA was significantly correlated with boiling point and STEL was only correlated with vapor pressure among physicochemical characteristics. Solubility and OWPC between “skin” and “no skin” substances which indicate skin penetration were not significantly different. Both LD50 and LC50 were correlated with TWA, while the LC50 was not with STEL. As health indicators, health rating and Emergency Response Planning Guidelines(ERPG) rating as recommended by the National Fire Protection Association(NFPA) and American Industrial Hygiene Association(AIHA) were associated with OELs and reflect the chemical hazards. Conclusions: We found relationships between OEL and chemical information including physicochemical characteristics and toxicological data. The study has an important meaning for understanding present regulatory OELs.

화학물질 관리 연구-2. 환경부와 고용노동부의 관리 화학물질의 구분, 노출기준 및 독성 지표 등의 특성 비교

김선주 ( Sun Ju Kim ),윤충식 ( Chung Sik Yoon ),함승헌 ( Seung Hon Ham ),박지훈 ( Ji Hoon Park ),김송하 ( Song Ha Kim ),김유나 ( Yu Na Kim ),이지은 ( Ji Eun Lee ),이상아 ( Sang Ah Lee ),박동욱 ( Dong Uk Park ),이권섭 ( Kwon Seob L 한국산업보건학회 2015 한국산업보건학회지 Vol.25 No.1

Objectives: The aims of this study were to investigate the classification system of chemical substances in the Occupational Safety and Health Act(OSHA) and Chemical Substances Control Act(CSCA) and to compare several health indices (i.e., Time Weighted Average (TWA), Lethal Dose (LD50), and Lethal Concentration (LC50) of chemical substances by categories in each law. Methods: The chemicals regulated by each law were classified by the specific categories provided in the respective law; seven categories for OSHA (chemicals with OELs, chemicals prohibited from manufacturing, etc., chemicals requiring approval, chemicals kept below permissible limits, chemicals requiring workplace monitoring, chemicals requiring special management, and chemicals requiring special heath diagnosis) and five categories from the CSCA(poisonous substances, permitted substances, restricted substances, prohibited substances, and substances requiring preparation for accidents). Information on physicochemical properties, health indices including CMR characteristics, LD50 and LD50 were searched from the homepages of the Korean Occupational and Safety Agency and the National Institute of Environmental Research, etc. Statistical analysis was conducted for comparison between TWA and health index for each category. Results: The number of chemicals based on CAS numbers was different from the numbers of series of chemicals listed in each law because of repeat listings due to different names (e.g., glycol monoethylether vs. 2-ethoxy ethanol) and grouping of different chemicals under the same serial number(i.e., five different benzidine-related chemicals were categorized under one serial number(06-4-13) as prohibited substances under the CSCA). A total of 722 chemicals and 995 chemicals were listed at the OSHA and its sub-regulations and CSCA and its sub-regulations, respectively. Among these, 36.8% based on OSHA chemicals and 26.7% based on CSCA chemicals were regulated simultaneously through both laws. The correlation coefficients between TWA and LC50 and between TWA and LD50, were 0.641 and 0.506, respectively. The geometric mean values of TWA calculated by each category in both laws have no tendency according to category. The patterns of cumulative graph for TWA, LD50, LC50 were similar to the chemicals regulated by OHSA and CCSA, but their median values were lower for CCSA regulated chemicals than OSHA regulated chemicals. The GM of carcinogenic chemicals under the OSHA was significantly lower than non-CMR chemicals(2.21 mg/m3 vs 5.69 mg/m3, p=0.006), while there was no significant difference in CSCA chemicals(0.85 mg/m3 vs 1.04 mg/m3, p=0.448). LC50 showed no significant difference between carcinogens, mutagens, reproductive toxic chemicals and non-CMR chemicals in both laws’ regulated chemicals, while there was a difference between carcinogens and non-CMR chemicals in LD50 of the CSCA. Conclusions: This study found that there was no specific tendency or significant difference in health indices such TWA, LD50 and LC50 in subcategories of chemicals as classified by the Ministry of Labor and Employment and the Ministry of Environment. Considering the background and the purpose of each law, collaboration for harmonization in chemical categorizing and regulation is necessary.