Papers by Young-Soo Chang
OSTI OAI (U.S. Department of Energy Office of Scientific and Technical Information), May 3, 2002
Public Law 91-596, "Occupational Safety and Health Act of 1970," Dec. 29, 1970, stimulated intere... more Public Law 91-596, "Occupational Safety and Health Act of 1970," Dec. 29, 1970, stimulated interest in modeling the impacts of interior noise on employees, as well as the intelligibility of interior public-address and other speech intra-communication systems. The classical literature on this topic has primarily featured a statistical uniform diffuse-field model. This was pioneered by Leo L. Beranek in the 1950s, based on energy-density formulations at the former Bell Telephone (AT&T) Laboratories in the years from 1930 to 1950. This paper compares the classical prediction approach to the most recent statistical methods. Such models were developed in the late 1970s and included innovations such as consideration of irregularly shaped (e.g., L-shaped) interior room spaces and coupled spaces.
OSTI OAI (U.S. Department of Energy Office of Scientific and Technical Information), 2022
This draft environmental impact statement (EIS) analyzes the impacts related to DOE's proposed en... more This draft environmental impact statement (EIS) analyzes the impacts related to DOE's proposed energy conservation standards for manufactured homes. DOE's proposed energy conservation standards are based on the 2021 International Energy Conservation Code (IECC) and relate to the building thermal envelope; air sealing; installation of insulation; duct sealing; heating, ventilation and air conditioning (HVAC); service hot water systems; mechanical ventilation fan efficacy; and heating and cooling equipment sizing. The draft EIS evaluates DOE's proposed action (energy conservation standards tiered based the manufacturers retail list price), alternatives to the proposed action (including energy conservation standards tiered based on size of the manufactured home and untiered standards), and a no action alternative. The draft EIS presents analysis of impacts related to (1) energy resources; (2) air resources (including greenhouse gases, climate change, ambient air quality and indoor air quality); (3) health and safety; (4) socioeconomics; and (5) environmental justice.
Assessment of health benefits from controlling air pollution in Shanghai, China
The large urban centers of the industrializing countries of the world are experiencing severe air... more The large urban centers of the industrializing countries of the world are experiencing severe air quality problems as their demands for energy increase faster than their ability to afford strong environmental protection. This situation is particularly true in the fast-growing part of Asia, where coal often provides the fuel for power generation and industrial development and where the transportation sector
, you may electronically access NUREG-series publications and other NRC records at the NRC's Libr... more , you may electronically access NUREG-series publications and other NRC records at the NRC's Library at www.nrc.gov/reading-rm.html. Publicly released records include, to name a few, NUREG-series publications; Federal Register notices; applicant, licensee, and vendor documents and correspondence; NRC correspondence and internal memoranda; bulletins and information notices; inspection and investigative reports; licensee event reports; and Commission papers and their attachments. NRC publications in the NUREG series, NRC regulations, and Title 10, "Energy," in the Code of Federal Regulations may also be purchased from one of these two sources:
Journal of Toxicology, 2013
The historical approach to assessing health risks of environmental chemicals has been to evaluate... more The historical approach to assessing health risks of environmental chemicals has been to evaluate them one at a time. In fact, we are exposed every day to a wide variety of chemicals and are increasingly aware of potential health implications. Although considerable progress has been made in the science underlying risk assessments for real-world exposures, implementation has lagged because many practitioners are unaware of methods and tools available to support these analyses. To address this issue, the US Environmental Protection Agency developed a toolbox of cumulative risk resources for contaminated sites, as part of a resource document that was published in 2007. This paper highlights information for nearly 80 resources from the toolbox and provides selected updates, with practical notes for cumulative risk applications. Resources are organized according to the main elements of the assessment process: (1) planning, scoping, and problem formulation; (2) environmental fate and tran...
Journal of Environmental Management, 2004
Urban development in the mega-cities of Asia has caused detrimental effects on the human health o... more Urban development in the mega-cities of Asia has caused detrimental effects on the human health of its inhabitants through air pollution. However, averting these health damages by investing in clean energy and industrial technologies and measures can be expensive. Many cities do not have the capital to make such investments or may prefer to invest that capital elsewhere. In this article, we examine the city of Shanghai, China, and perform an illustrative cost/benefit analysis of air pollution control. Between 1995 and 2020 we expect that Shanghai will continue to grow rapidly. Increased demands for energy will cause increased use of fossil fuels and increased emissions of air pollutants. In this work, we examine emissions of particles smaller than 10 mm in diameter (PM 10), which have been associated with inhalation health effects. We hypothesize the establishment of a new technology strategy for coal-fired power generation after 2010 and a new industrial coaluse policy. The health benefits of pollution reduction are compared with the investment costs for the new strategies. The study shows that the benefit-to-cost ratio is in the range of 1-5 for the power-sector initiative and 2-15 for the industrial-sector initiative. Thus, there appear to be considerable net benefits for these strategies, which could be very large depending on the valuation of health effects in China today and in the future. This study therefore provides economic grounds for supporting investments in air pollution control in developing cities like Shanghai.
Journal of the Air & Waste Management Association, 2001
24)-were selected on the basis of morning (7:00 a.m.-10:00 a.m.) average wind direction and speed... more 24)-were selected on the basis of morning (7:00 a.m.-10:00 a.m.) average wind direction and speed and daily maximum O 3 concentrations in the greater Seoul, Korea, of 1990-1997. To better understand their characteristics and life cycles, surface data from the Seoul Weather Station (SWS) and surface and 850-hPa wind field data covering northeast Asia around the Korean Peninsula were used for the analysis. In the July 1992 episode, westerly winds were most frequent as a result of the influence of a high-pressure system west of the Korean Peninsula behind a trough. In contrast, in the July 1994 episode, easterly winds were most frequent as a result of the effect of a typhoon moving north from the south of Japan. Despite different prevailing wind directions, the peak O 3 concentrations for each episode occurred when a sea/land breeze developed in association with weak synoptic forcing. The August 1994 episode, which was selected as being representative of calm conditions, was another typical example in which a well-developed IMPLICATIONS Both regional factors, such as the long-range transport of O 3 precursors, and local factors, such as meteorology induced by terrains combined with emission patterns, can play a part in O 3 problems. Korea is located downwind of prevailing westerlies from China, whose rapid industrialization in recent years has been affecting the environmental quality of northeast Asia. In Korea, low wind speeds and high densities of precursor emissions are conducive to photochemical O 3 pollution. This paper deals with the evolution of high O 3 episodes representative of the greater Seoul area, where elevated O 3 levels frequently occur. Results from this study can be used to determine environmental factors conducive to high O 3 levels, build databases to support O 3 warning systems, and develop coherent O 3 control strategies. sea/land breeze helped cause the peak O 3 concentration to rise to a record high of 322 parts per billion by volume (ppbv). All three high O 3 episodes ended as a result of precipitation, and subsequent rises in O 3 concentrations were also suppressed by a series of precipitation events afterwards. In particular, two heavy rainfalls were the main reason why the August 1994 episode, which had the highest and second-highest O 3 concentrations, lasted only a few days.
Asian Journal of Atmospheric Environment, 2010
To identify the domains that have the greatest impacts on air quality at the surface, both the up... more To identify the domains that have the greatest impacts on air quality at the surface, both the upwind and downwind areas of Seoul were determined by season using refined wind fields. Four consecutive days were selected as the study period typical of each season. The mesoscale meteorology of the study period was reproduced by using the MM5 prognostic meteorological model (PSU/NCAR Mesoscale Model) with horizontally nested grids. The gridded meteorological field, which was used on the study area of 242 km×226 km with grid spacing of 2 km, was generated by using the CALMET diagnostic meteorological model. Upwind and downwind areas of Seoul were determined by calculating 24-hour backward and forward air parcel trajectories, respectively, with u, v, and w velocity vectors. The results showed that the upwind and downwind areas were extended far to the northwest and the southeast as a result of high wind speeds in the spring and winter, while they were restricted on the fringe of Seoul in the summer and fall.
Aerosol and Air Quality Research, 2015
Concentrations of fine (PM 2.5) and coarse (PM 10-2.5) particles, whose aerodynamic diameters are... more Concentrations of fine (PM 2.5) and coarse (PM 10-2.5) particles, whose aerodynamic diameters are less than or equal to 2.5 µm, and greater than 2.5 and less than or equal to 10 µm, respectively, at ambient air monitoring stations in Seoul between 2002 and 2008 were analyzed. Effects of Asian dust are mainly manifested as concentration spikes of PM 10-2.5 , but were considerable on PM 2.5 levels in 2002 when Asian dust storms were the strongest. Excluding the effects of Asian dust, annual average PM 2.5 showed a downward trend. Despite a similarity in year-to-year variations, PM 10-2.5 , mostly affected by fugitive dust emissions, and CO and NO 2 , primarily affected by motor vehicle emissions, did not show a decrease. PM 2.5 along with CO and NO 2 had peak concentration during the morning rush hour; the PM 10-2.5 peak lagged one hour behind the PM 2.5 peak. On high PM 2.5 days, PM 2.5 peaks occurred two hours later than usual as the effects of secondary formation through photochemical reactions became more important. A test for the spatial variability shows that PM 10-2.5 , which is known to be greatly influenced by local effects, is lower in its correlation coefficient and higher in its coefficient of divergence (COD, which serves as an indicator for spatial variability) than PM 2.5 , albeit by only a small difference. The average COD of PM 2.5 among monitoring stations was about 0.2 but was lowered to 0.13 when considering high PM 2.5 days only, signifying that spatial uniformity increases due to the pervasive influence of photochemical reactions.
A Study of the Effects of Gas Well Compressor Noise on Breeding Bird Populations of the Rattlesnake Canyon Habitat Management Area, San Juan County, New Mexico
Assessing Human Health and Environmental Impacts of Air Pollutants
Air pollutants generated routinely or accidentally by human activities and by natural processes c... more Air pollutants generated routinely or accidentally by human activities and by natural processes can threaten human health and the environment. We have completed numerous projects that required consequence assessment and risk quantification for air ...
Aerosol and Air Quality Research, 2017
Particulate species were measured in April-May 2003 at two sites, one in the megacity of Seoul an... more Particulate species were measured in April-May 2003 at two sites, one in the megacity of Seoul and the other in the Deokjeok Island to the west of Seoul, to examine the effects of long-range transport under the influence of prevailing westerlies. The effects of Asian dust were observed in April, and a severe smog episode occurred in late May. During May, all air pollutants showed negative correlations with wind speed at Seoul, particularly for NO 2 and CO, a large proportion of which result from vehicle emissions. SO 4 2continued to increase in association with an inflow of air pollutants from China with heavy use of coal, with fluctuations depending on wind speed. The smog episode in late May occurred as emissions from Siberian forest fires were superimposed on pollutant inflows from China that had persisted since early May and local emissions accumulated under stagnant conditions. During the episode, Siberian forest fires increased K + while local emissions primarily from vehicles increased NO 3-, OC, and EC. The effects of an inflow of air pollutants from the outside were significant at Deokjeok, with small local emissions, resulting in substantial increases in Ca 2+ during the Asian dust event and SO 4 2during the smog episode, compared to those at Seoul. Because both sites were strongly influenced by the effects of long-range transport in May, PM 2.5 along with SO 4 2and K + exhibited a strong correlation between Seoul and Deokjeok.
Asian Journal of Atmospheric Environment, 2016
Particle-phase concentrations were measured at 10, 80, and 200 m from the roadside of a national ... more Particle-phase concentrations were measured at 10, 80, and 200 m from the roadside of a national highway near Seoul in January and May 2008. The highway has two lanes each way, with an average hourly traffic volume of 1,070 vehicles. In January 2008, PM 10 concentrations decreased from 10 to 80 m but increased at 200 m. Black carbon (BC) decreased only slightly with distance due to the influence of biomass burning and open burning from the surrounding areas. In May 2008, the effect of secondary formation on both PM 10 and PM 2.5 was significant due to high temperatures compared with January. Because on-road emissions had little effect on secondary formation for a short time, variations in PM 10 concentrations became smaller, and PM 2.5 concentrations increased with distance. The effects of fugitive dust on PM concentrations were greater in May than in January when the mean temperature was below freezing. In the composition variations, the amounts of primary ions, organic carbon (OC), and BC were larger in January, while those of secondary ions and others were larger in PM 10 , as well as PM 2.5 in May.
Atmospheric Environment (1967), 1986
The aerosol equilibrium formulation of Stelson and Seinfeld (1982a, b, Atmospheric Enrironment 16... more The aerosol equilibrium formulation of Stelson and Seinfeld (1982a, b, Atmospheric Enrironment 16, 983-992. 993-1000) is incorporated into the STEM-II transport/chemistry model and is evaluated against NH,, HNOB and aerosol NH: and NO; measured at Nagano Prefecture, Japan on 29 and 30 July 1983. These results indicate that this modeling approach is useful in analyzing field data. I. INTRODUCTION
An approach for assessing human exposures to chemical mixtures in the environment
Toxicology and Applied Pharmacology, 2008
Humans are exposed daily to multiple chemicals, including incidental exposures to complex chemica... more Humans are exposed daily to multiple chemicals, including incidental exposures to complex chemical mixtures released into the environment and to combinations of chemicals that already co-exist in the environment because of previous releases from various sources. Exposures to chemical mixtures can occur through multiple pathways and across multiple routes. In this paper, we propose an iterative approach for assessing exposures to environmental chemical mixtures; it is similar to single-chemical approaches. Our approach encompasses two elements of the Risk Assessment Paradigm: Problem Formulation and Exposure Assessment. Multiple phases of the assessment occur in each element of the paradigm. During Problem Formulation, analysts identify and characterize the source(s) of the chemical mixture, ensure that dose-response and exposure assessment measures are concordant, and develop a preliminary evaluation of the mixture's fate. During Exposure Assessment, analysts evaluate the fate of the chemicals comprising the mixture using appropriate models and measurement data, characterize the exposure scenario, and estimate human exposure to the mixture. We also describe the utility of grouping the chemicals to be analyzed based on both physical-chemical properties and an understanding of environmental fate. In the article, we also highlight the need for understanding of changes in the mixture composition in the environment due to differential transport, differential degradation, and differential partitioning to other media. The Results section describes the application of the method to various chemical mixtures, highlighting issues associated with assessing exposures to chemical mixtures in the environment.
Uploads
Papers by Young-Soo Chang