• International Journal of High-Rise Buildings
• /
• v.10 no.4
• /
• pp.345-364
• /
• 2021

Developments in the understanding of fire behaviour for large open-plan spaces typical of tall buildings have been greatly outpaced by the rate at which these buildings are being constructed and their characteristics changed. Numerous high-profile fire-induced failures have highlighted the inadequacy of existing tools and standards for fire engineering when applied to highly-optimised modern tall buildings. With the continued increase in height and complexity of tall buildings, the risk to the occupants from fire-induced structural collapse increases, thus understanding the performance of complex structural systems under fire exposure is imperative. Therefore, an accurate representation of the design fire for open-plan compartments is required for the purposes of design. This will allow for knowledge-driven, quantifiable factors of safety to be used in the design of highly optimised modern tall buildings. In this paper, we review the state-of-the-art experimental research on large open-plan compartment fires from the past three decades. We have assimilated results collected from 37 large-scale compartment fire experiments of the open-plan type conducted from 1993 to 2019, covering a range of compartment and fuel characteristics. Spatial and temporal distributions of the heat fluxes imposed on compartment ceilings are estimated from the data. The complexity of the compartment fire dynamics is highlighted by the large differences in the data collected, which currently complicates the development of engineering tools based on physical models. Despite the large variability, this analysis shows that the orders of magnitude of the thermal exposure are defined by the ratio of flame spread and burnout front velocities (V_S / V_BO), which enables the grouping of open-plan compartment fires into three distinct modes of fire spread. Each mode is found to exhibit a characteristic order of magnitude and temporal distribution of thermal exposure. The results show that the magnitude of the thermal exposure for each mode are not consistent with existing performance-based design models, nevertheless, our analysis offers a new pathway for defining thermal exposure from realistic fire scenarios in large open-plan compartments.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.24 no.4
• /
• pp.446-452
• /
• 2014

Objective: This study aimed to evaluate the exposure status of formaldehyde(FA) among the nurses in ambulatory care departments of university hospital. Methods: Two university hospitals were surveyed. The FA concentration in air were measured to target 62 nurses in 8 ambulatory care departments(89 samples). Air sampling and analysis of FA were carried out according to the OSHA Method ID-205. The survey was conducted with questionnaire asking about how to control FA and whether the nurses use the formaldehyde protectors or not. Results: FA was detected in all samples. The maximum concentration of FA was 0.258 ppm and the geometric mean was 0.023 ppm. There was no sample that exceeded any of exposure standards by OSHA-TWA whereas there were 54 samples(60.7%) that exceeded the standards by NOISH-TWA. Among 62 nurses handling FA, 13 nurses(21.0%) used the protective gloves while nobody used a gas mask. It was assessed that any of 8 common ambulatory care departments did not use a safety cabinet for FA in which local exhaust ventilation was fixed. Conclusions: Nurses in ambulatory care departments were exposed to FA. Therefore, the environment management of a workplace, the health management of a nurses, FA handling education and installing a FA cabinet with a local exhaust ventilation were needed because FA as a carcinogen was able to cause any cancer to a human body if it was emitted in air for long time.

• Journal of Environmental Health Sciences
• /
• v.46 no.2
• /
• pp.150-158
• /
• 2020

Objective: This study is designed to measure the concentration of DBPs (disinfection by-products) in pool water and in air and to estimate the carcinogenic potential through the evaluation of inhalation exposure. Methods: The subjects were six indoor swimming pools with many users in Gwangju. Samples of pool water and indoor air were taken every one month from August 2018 to August 2019 and analyzed for eight swimming pool standards. Three-liter air samples were collected and the VOCs were analyzed using GC/MS directly connected to thermal desorption. Results: pH was 6.8-7.5 and the concentration of free residual chlorine in pool water was 0.40-0.96 ?/ℓ. Physicochemical test items such as KMnO₄ consumption and heavy metal items such as Aluminum met existing pool hygiene standards. No VOC materials were detected except for the DBPs. The concentration of THMs in the pool water was 11.05-41.77 ㎍/L and the THMs mainly consist of Chloroform (63-97%) and BDCM (3-31%). The concentration of indoor air THMs is 13.24-32.48 ㎍/㎥ and consists of Chloroform. The results of carcinogenic assessment of chloroform in the indoor swimming pool via inhalation exposure were 2.0 to 6.4 times higher than the 'acceptable risk level' suggested by the US EPA. Conclusions: The concentration of THMs in the pool water is 11.05-41.77 ㎍/L, most of which is chloroform. In addition, the concentration of indoor air THMs is 13.24-32.48 ㎍/㎥. The result of carcinogenic assessment of chloroform was 2.0 to 6.4 times higher than the 'acceptable risk level' suggested by the US EPA.

• Journal of the Korean Society of Costume
• /
• v.35
• /
• pp.135-149
• /
• 1997

In this thesis the northeast Asian footwear culture are examined,. in order to search the origin It started from the cradle of ancient civilization such as Meospotamia Egypt Indus and ancient China civilization region prior to the northeast Asia. The results are: On account severe intense climates and rough road as well ancient people starts to put the shoes on. Primitive form of ancient footwear put into the two categories: Chinese in the central land begins to put the shoes named Lee. After making contact with nomadic northern races boots named Wha is adopted functionally and taken throughout China. oreans wear the shoes both boots and shoes named Lee. Japanese walked with bare feet and simul-taneously Dagetta was used for rice farming. The changes of footwear is mainly in-fluenced by the factors such as climate con-dition social economic prohibition func-tional elements and aesthetic standards. Cli-mate conditions have influence upon the footwear materials form and foot exposure, The functional elements influenced on the ways of wearing shoes. Decorated patterns and materials of footwear is under the influnece of social economic prohibition and also affected by aesthetic standards(Tab 1-4) In accordance with pattern function materials of footwear the type and characteristics of footwear in China Korea nd japan came out with diversity(Tab 5-9)

• Environmental Analysis Health and Toxicology
• /
• v.24 no.4
• /
• pp.293-301
• /
• 2009

This study was conducted to investigate the distribution of the concentrations of selected trace metals and inorganic anions in five types of drinking water samples (mineral spring water, well water, small community water, municipal tap water, and commercial mineral water) collected from Chuncheon, Gangwon-do in 2007. Forty four samples were analyzed for five metals and five anions using an atomic absorption spectrometer and an ion chromatograph, respectively. Arsenic (As) and nitrate (${NO_3}^-$) concentrations in some groundwater samples did not meet the future (10 ${\mu}g/L$) and current (44 mg/L) Korean drinking water standards, respectively. On the other hand, any municipal tap water samples, the sources of which were lake surface water, satisfied the Korean standards. Human health risk assessment results showed that arsenic in all types of water, especially groundwater including commercial mineral water, may pose both noncarcinogenic and carcinogenic effects on the residents. It is concluded that groundwater is not safe drinking water any longer and that a national survey and follow-up measures need to be taken.

• Biomedical Science Letters
• /
• v.22 no.3
• /
• pp.65-74
• /
• 2016

The critical aspects of biosafety and bio-containment have been increasingly important in recent years. Biological agents involved in biological research projects at the Nanyang Technological University (NTU) Singapore are usually those with low risks. Biosafety level 2 or BSL 2 laboratories are widely used. However, biosafety measures which refer to the implementation of laboratory practices and procedures, specific construction features of laboratory facilities and safety equipment must be in place to reduce the exposure of laboratory personnel, the public or the environment to potentially infectious agents or other biological hazards. It is also required to pay more attention to laboratory-acquired infections (LAIs) which may occur in research laboratories, clinical laboratories or animal facilities. BSL 2 audit and certification program is implemented as an internal exercise covering laboratories in the university where biological agents are handled or biological research works are carried out. We have put some efforts to raise biosafety standards university-wide in both laboratory infrastructure and laboratory practices to a higher level. Common audit findings are briefly discussed in this presentation.

• Journal of Korean society of Dental Hygiene
• /
• v.19 no.5
• /
• pp.635-649
• /
• 2019

Objectives: This literature review seeks to identify the current status of the liberal arts education of dental hygiene majors offered by universities in Korea and the U.S. and provide a comparative analysis of the data on liberal arts education in both countries. Methods: From April 3, 2017 to May 1, 2017, research data on curriculum topics were collected from 60 selected universities. The data were collected from university websites, which also provided the universities' emails and dental hygiene major descriptions. We calculated the descriptive statistics of the variables and performed independent t-tests on the data. Results: In all the domains of the NCS and K-CESA, the dental hygiene major currently offers courses on language and communication and general education, focusing on self-management and development. Few universities offer subjects from other disciplines. Conclusions: Pro-actively exploring strategies is a prerequisite to the systematic operation of standardized dental hygiene education. It is imperative to conduct research consistently on relevant topics, such as teaching methods, general education standards, and connectivity between major subjects and the goals and effects of exposure to a general education.

• Journal of Environmental Health Sciences
• /
• v.50 no.1
• /
• pp.1-5
• /
• 2024

International Commission on Radiological Protection (ICRP) is an independent international organization that advances the science of radiological protection for the public benefit, particularly by providing recommendations and guidance on all aspects of protection against ionizing radiation. The ICRP is a community of more than 380 globally-recognized experts in radiological protection science, policy, and practice from more than 50 countries. As of January 2024, the ICRP is comprised of a Main Commission, the Scientific Secretariat, four Standing Committees, and 30 Task Groups under the four committees. The ICRP has released well over one hundred publications on all aspects of radiological protection. Most address a particular area within radiological protection, but a handful of the publications, the so-called fundamental recommendations, describe the overall system of radiological protection. The system for radiological protection is based on the current understanding of the science of radiation exposure and its effects along with value judgements. The ICRP offers recommendations to regulatory and advisory agencies and provides advice to management and professional staff with responsibilities for radiological protection. Legislation in most countries adheres closely to ICRP recommendations. The International Atomic Energy Agency's (IAEA) International Basic Safety Standards are based heavily on ICRP recommendations. ICRP recommendations form the core of radiological protection standards, legislation, programs, and practice worldwide.

• Progress in Medical Physics
• /
• v.20 no.4
• /
• pp.253-259
• /
• 2009

We have developed standards based on international criterions for the quality control of dose tested by the measurement institutions of individual exposure doses through improving the reliability of data on the exposure dose of individuals working in radioactive environment and securing the accuracy and reliability of individual dose measurements. Laws related to radiation dose applied to domestic institutions refer to ANSI N13.11.1993, but currently, in U.S. and some other countries the measurement of radiation doses is based on ANSI N13.11.2001 that reduced test categories and tightened the standards. We made efforts to simplify the standards and to reduce the number of dosimeters required in experiment, and avoided preventing or hindering the use of future technologies not approved under the current law such as glass dosimeter and optical stimulation dosimeter. The Quality Management Manual of Radiation Dosimetry Service, Assessment Manual of Radiation Dosimetry Service Accreditation Program, and the Personnel Dosimetry Performance. Criteria for Testing are documents applicable in supervising laboratories.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.3 no.1
• /
• pp.110-126
• /
• 1993

Worker exposures to total chromium, hexavalent chromium (VI), sulfuric acid and alkaline dust at electroplating operations and worker exposures to trichloroethylene (TCE) and methyl chloroform (MCM) at degreasing operations in eleven small industrial plants were evaluated. Appropriate local exhaust ventilation systems for both operations were designed and recommended. Results of the study are summarized as follows ; 1. Out of 134 measurements for airborne hexavalent chromium concentrations, seven were exceeding the Korean occupational health standard of $50{\mu}g/m^3$ and 45 were exceeding the NIOSH standard of $1{\mu}g/m^3$. With an exception of one measurement, concentrations of total chromium were below the Korean standard of $500{\mu}g/m^3$. 2. Worker exposures to chromium were closely related to the existing control methods at the electroplating operations. Local exhaust systems, partial coverage of the tank surface, and antifoaming agents on liquid surface were adopted as control methods. 3. With an exception of one sample, airborne concentrations of sulfuric acid and alkaline dusts were below the applicable occupational heatlth standards. 4. Three plants indicated that airborne concentrations of TCE and MCM were exceeding the Korean standards. Other plants showed lower concentrations than the standards. It should be noted that generally, the activities and workloads on the day of surveys were less than normal. 5. Since the most existing ventilation systems did not satisfy the ACGIH criteria, the ventilation systems should be improved. Some examples for designing appropriate ventilation systems are presented.