• Safety and Health at Work
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• v.15 no.1
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• pp.114-117
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• 2024

A lithium-ion battery is a rechargeable battery that uses the reversible reduction of lithium ions to store energy and is the predominant battery type in many industrial and consumer electronics. The lithium-ion batteries are essential to ensure they operate safely. We conducted an exposure assessment five days after a fire in a battery-testing facility. We assessed some of the potentially hazardous materials after a lithium-ion battery fire.We sampled total suspended particles, hydrogen fluoride, and lithium with real-time monitoring of particulate matter (PM) 1, 2.5, and 10 micrometers (㎛). The area sampling results indicated that primary potential hazardous materials such as dust, hydrogen fluoride, and lithium were below the recommended limits suggested by the Korean Ministry of Labor and the American Conference of Governmental Industrial Hygienists Threshold Limit Values. Based on our assessment, workers were allowed to return to work.

• Journal of the Korea Safety Management & Science
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• v.14 no.3
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• pp.135-141
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• 2012

This study was conducted to evaluate the characteristics of exposure to asbestos for ship repair workers in Korea by a systematic review. The number of articles studying asbestos exposure levels from ship repair workplaces was found to be 4. All asbestos concentration reported as either geometric mean and geometric standard deviation or ranges were transformed to arithmetic mean to estimate exposure level. In addition, weighted arithmetic means(WAMs) were calculated by weighing of the different number of samples. The WAM concentrations were 2.746 f/cc during asbestos dismantling work, 0.034 f/cc before asbestos dismantling work and 0.065 f/cc after working respectively. The maximum airborne concentration of asbestos during asbestos removal work was 7.02 f/cc which was 70 times higher than the occupational exposure limit of Korea, 0.1 f/cc. This study recommends that retrospective exposure to asbestos based on various ship types and operations should be assessed.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.23 no.2
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• pp.148-155
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• 2013

Objectives: This study was performed in order to compare the average levels and similarity of occupational exposure limits in South Korea, the U.S., the E.U., Germany, Japan and Finland. Methods: In this study, occupational exposure limits (OELs) for one hundred and seventy seven hazardous substances which are managed in the workplace by the Occupational Safety and Health Act in South Korea were matched with those of other countries. The units for the exposure limits of the same substance (identical CAS number) were unified and the exposure limits in each country were compared with threshold limit values (TLVs) of the American Conference of Governmental Industrial Hygienists (ACGIH) using a geometric mean method. Geometric similarity was calculated to assess the association by each country. Results: The exposure limits according to ACGIH TLVs in South Korea, the E.U., Germany, Japan, and Finland were 148, 37, 76, 90, and 110, respectively. When using TLVs of ACGIH as a standard, the geometric mean ratios of Germany, Finland, the E.U., South Korea, and Japan were 0.79, 0.80, 0.82, 1.19, and 1.27, respectively. Geometric similarity with TLVs of ACGIH was highest in South Korea (0.75) followed by Japan (0.56), the E.U. (0.52), Finland (0.50), and Germany (0.46). Conclusions: Through the comparison of levels of OELs and similarities among South Korea, the U.S., the E.U., Germany, Japan, and Finland, we could better understand the characteristics of occupational exposure limits by country.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.18 no.1
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• pp.32-40
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• 2008

Methyl bromide has been used as a representative fumigant for quarantine, and several poisoning cases have occurred recently by this chemical in Korea. The purpose of this study is to evaluate workers' exposures to airborne methyl bromide in the importing and exporting plant products quarantine companies. Air samples were collected 400/200 mg Anasorb 747TM and were analyzed by gas chromatograph /flame ionization detector according to the Occupational Safety and Health Agency (OSHA) Method PV2040. Geometric mean (GM) and arithmetic mean (AM) of total 27 workers' exposure concentrations to airborne methyl bromide were 1.12 ppm and 0.24 ppm, respectively. Two exposures(12.1 ppm and 12 ppm as 8hr-TWA) of total 27 workers' exposures exceeded the Korean standard (5 ppm) of Ministry Labor, while 4 exposures (15%) exceeded the Threshold Limit Value (TLV) (1 ppm) of American Conference of Governmental Industrial Hygienists (ACGIH). Seven samples (11%) of total 63 short-term air samples exceeded the OSHA Permissible Exposure Limit (PEL) 20 ppm (Ceiling). The opening (management) task in wood fumigation by tent showed the highest short-term exposure concentrations (AM: 18.6 ppm, GM: 0.58 ppm, maximum: 340.7 ppm). The maximum level in treatment task of the same process was 2.01 ppm. Methyl bromide concentrations in opening operation was significantly higher than that in treatment operation (p<0.05). In conclusion, the GM of workers' 8hr-TWA exposures to airborne methyl chloride in the importing/exporting plant quarantine industry was estimated below the ACGIH TLV (1 ppm). However, opening task in the fumigation of wood being covered with tent or fumigation of pant products in container showed the levels exceeding ACGIH TLV (1 ppm), and opening task in the fumigation of wood being covered with tent showed the level exceeding the Korean standard of Ministry of Labor (5 ppm).

• Safety and Health at Work
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• v.6 no.4
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• pp.312-316
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• 2015

Background: Unleaded petrol contains significant amounts of monocyclic aromatic hydrocarbons such as benzene, toluene, and xylenes (BTX). Toxic responses following occupational exposure to unleaded petrol have been evaluated only in limited studies. The main purpose of this study was to ascertain whether (or not) exposure to unleaded petrol, under normal working conditions, is associated with any hepatotoxic or nephrotoxic response. Methods: This was a cross-sectional study in which 200 employees of Shiraz petrol stations with current exposure to unleaded petrol, as well as 200 unexposed employees, were investigated. Atmospheric concentrations of BTX were measured using standard methods. Additionally, urine and fasting blood samples were taken from individuals for urinalysis and routine biochemical tests of kidney and liver function. Results: The geometric means of airborne concentrations of BTX were found to be $0.8mg\;m^{-3}$, $1.4mg\;m^{-3}$, and $2.8mg\;m^{-3}$, respectively. Additionally, means of direct bilirubin, alanine aminotransferase, aspartate aminotransferase, blood urea and plasma creatinine were significantly higher in exposed individuals than in unexposed employees. Conversely, serum albumin, total protein, and serum concentrations of calcium and sodium were significantly lower in petrol station workers than in their unexposed counterparts. Conclusion: The average exposure of petrol station workers to BTX did not exceed the current threshold limit values (TLVs) for these chemicals. However, evidence of subtle, subclinical and prepathologic early liver and kidney dysfunction was evident in exposed individuals.

• Safety and Health at Work
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• v.12 no.2
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• pp.209-216
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• 2021

Background: The article presents the results of studies performed in order to develop a new method of airborne potassium bromate(V) determination at workplaces. Methods: The method is based on a collection of the inhalable fraction of potassium bromate(V) using the IOM Sampler, then extraction of bromates with deionized water and chromatographic analysis of the obtained solution. The analysis was performed using ion chromatography with conductometric detection. The tests were performed on a Dionex IonPac®AS22 analytic column (250 × 4 mm, 6 ㎛) with AG22 precolumn (50 × 4 mm 11 ㎛). Results: The method provides for potassium bromate(V) determination within the concentration range of 0.043 ÷ 0.88 mg/m³ for an air sample of 0.72 m³ in volume, i.e., 0.1-2 times the exposure limit value as proposed in Poland. The method was validated in accordance with PN-EN 482. The obtained validation data are as follows: measuring range: 3.1-63.4 ㎍/mL, limit of detection (LOD) = 0.018 ㎍/mL and limit of quantification (LOQ) = 0.053 ㎍/mL. The developed method has been tested in the work environment, on laboratory employees having contact with potassium bromate(V). Conclusion: The analytical method allowed the determination of the inhalable fraction of airborne potassium bromate(V) at workplaces and can be used to assess occupational exposure.

• Nuclear Engineering and Technology
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• v.53 no.1
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• pp.351-356
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• 2021

Korean nuclear power plants (NPPs) have various radiation protection programs to attain radiation exposure as low as reasonably achievable (ALARA). In terms of ALARA, this paper provides a comprehensive overview of administrative dose control for occupationally-exposed workers in Korean NPPs. In addition to dose limits, administrative dose constraints are implemented to resolve an inequity of radiation exposure in which some individuals in NPPs receive relatively higher doses than others. Occupational dose constraints in Korean NPPs are presented in this paper with the background of how those values were determined. For pressurized water reactors, 80% and 90% of the annual average limit for an effective dose, 20 mSv/y, are set as the primary and secondary dose constraints, respectively. Pressurized heavy water reactors (PHWRs) have also established the primary and secondary dose constraints corresponding to 70% and 80% of the effective dose limit, and additional constraints for tritium concentration are provided to control internal exposure in PHWRs. Follow-up measures for exceeding these administrative dose constraints are also introduced compared to exceeding the dose limits. Finally, analysis results of dose distributions show how the implementation of administrative dose constraints impacted the occupational dose distributions in Korean NPPs during the years 2009-2018.

• Safety and Health at Work
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• v.13 no.3
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• pp.357-363
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• 2022

Background: Refractory ceramic fibers (RCFs) are a suspected carcinogen but have been widely used as insulations. Depending on the temperature, RCFs can transform into crystalline SiO₂, which is a carcinogen that can be present in the air during bulk RCF handling. This study analyzed the physicochemical and morphological characteristics of RCFs at high temperatures and determined the exposure levels during the semiconductor scrubber maintenance. Methods: Sampling was conducted at a company that manufactures semiconductor scrubbers using RCFs as insulation. Bulk RCF samples were collected both before and after exposure to a scrubber temperature of 700℃. Airborne RCFs were collected during scrubber maintenance, and their characteristics were analyzed using microscopes. Results: The components of bulk RCFs were SiO₂ and Al₂O₃, having an amorphous structure. Airborne RCFs were morphologically different from bulk RCFs in size, which could negatively affect maintenance workers' health. 58% of airborne RCFs correspond to the size of thoracic and respirable fibers. RCFs did not crystallize at high temperatures. The exposure caused by airborne RCFs during the scrubber frame assembly and insulation replacement was higher than the occupational exposure limit. Conclusion: Workers conducting insulation replacement are likely exposed to airborne RCFs above safe exposure limits. As RCFs are suspected carcinogens, this exposure should be minimized through prevention and precautionary procedures.

• Safety and Health at Work
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• v.13 no.4
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• pp.493-499
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• 2022

Background: The purpose of this study is to construct a job-exposure matrix for lead that accounts for industry and work processes within industries using a nationwide exposure database. Methods: We used the work environment measurement data (WEMD) of lead monitored nationwide from 2015 to 2016. Industrial hygienists standardized the work process codes in the database to 37 standard process and extracted key index words for each process. A total of 37 standardized process codes were allocated to each measurement based on an automated key word search based on the degree of agreement between the measurement information and the standard process index. Summary statistics, including the arithmetic mean, geometric mean, and 95th percentile level (X95), was calculated according to industry, process, and industry process. Using statistical parameters of contrast and precision, we compared the similarity of exposure groups by industry, process, and industry process. Results: The exposure intensity of lead was estimated for 583 exposure groups combined with 128 industry and 35 process. The X95 value of the "casting" process of the "manufacture of basic precious and non-ferrous metals" industry was 53.29 ㎍/m³, exceeding the occupational exposure limit of 50 ㎍/m³. Regardless of the limitation of the minimum number of samples in the exposure group, higher contrast was observed when the exposure groups were by industry process than by industry or process. Conclusion: We evaluated the exposure intensities of lead by combination of industry and process. The results will be helpful in determining more accurate information regarding exposure in lead-related epidemiological studies.

• Journal of Environmental Health Sciences
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• v.27 no.3
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• pp.1-10
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• 2001

This study was performed to evaluate chromium in air and chromium concentrations in whole blood and urine of workers at chrome plating factories, and to determine the correlation between environmental and biological chromium levels. This study involved 29 workers as study group and 24 undergraduate students as control group. The geometric means(GM) of airborne hexavalent chromium and total chromium concentrations in the plating factories were 3.4 $\mu\textrm{g}$/㎥ and 10.8 $\mu\textrm{g}$/㎥, respectively. Hexavalent chromium levels in two of total 29 measurements exceeded the korean occupational exposure limit and the American Conference of Governmental Industrial Hygienists Threshold Limit Value(ACGIH-TLV) of 50$\mu\textrm{g}$/㎥. Only one sample for total chromium exceeded the Korea occupational exposure limits, the ACGIH-TLV, and the National Institute for Occupational Safety and Health Recommended Exposure Limits(NIOSH-REL) of 500 $\mu\textrm{g}$/㎥. The GM of chromium concentrations in blood and urine of workers exposed to chromium were 8.4 $\mu\textrm{g}$/L and 11.9 $\mu\textrm{g}$/L. The GM of chromium concentrations in blood and urine of workers exposed to chromium were 8.4 $\mu\textrm{g}$/L and 11.9 $\mu\textrm{g}$/L, respectively, whereas the chromium concentrations in blood and urine of the controls were 1.6 $\mu\textrm{g}$/L and 3.8 $\mu\textrm{g}$/L, respectively. There were statistically significant differences of blood and urine concentrations between study group and control group (p<0.01). The chromium concentrations in urine were most highly related to hexavalent chromium, concentration in air(r=0.642, p<0.01). Also, there was a relatively high correlation between the hexavalent chromium concentrations in air and chromium concentrations in whole blood(r=0.557, p<0.05). These results indicate that whole-blood chromium with urinary chromium could be an indicator of chromium body burden caused by exposure to chromic acid mist in plating operation.