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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Personal noise exposure in platinum concentrator operations in the bushveld complex of South Africa

Deysel, Willem Bernardus January 2017 (has links)
A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in partial fulfillment of the requirements for the degree of Masters in Public Health: Occupational Hygiene Johannesburg, June 2017 / Introduction The quantification and interpretation of personal noise exposure levels in the platinum processing industry of South Africa is an important research topic. Very few studies have been done nationally and internationally on noise exposure in this industry, given the serious health effects of over exposure to noise and the large number of people employed in this industry, this study is important. Objectives The objectives of this study were to describe personal noise exposure measurements of permanent and long term contractor employees during 2012 to 2014 at five Platinum Concentrator operations; to compare the personal noise exposure levels of the different activity areas between the five Platinum Concentrator operations; and to compare the personal noise exposure measurements of the Platinum Concentrator operations to national and international exposure limits. Methods This study was a cross-sectional secondary data analysis of personal noise exposure levels measured as part of routine Occupational Hygiene sampling programme during the period of 2012 to 2014 and was done in five platinum concentrator operations situated in the Bushveld Complex of South Africa. A total of 720 samples were extracted from an electronic database and descriptive statistics were applied to analyse the data. Results This study found that the Processor Grade 2 occupation within platinum concentrator no.3 had the highest personal noise exposure (104.7dBA) with a median personal noise exposure of 87.35dBA and a geometric mean personal noise exposure of 87.4dBA. Sixty seven percent of the personal noise measurements within the five Concentrator Operations exceeded the South African Occupational Exposure Limit of 85dBA and 19.71% of the personal noise measurement results exceeded the OSHA Exposure Limit of 90dBA. Conclusion This study indicated that over exposure to noise in the platinum processing industry can occur; therefore further research on this topic and in this industry is warranted. / MT2017
2

Airborne endotoxin exposures to grain elevator workers is independent of dust concentration (presentation)

Bartlett, Karen H., Dimich-Ward, Helen, Chan-Yeung, Moira, Kennedy, Susan M. January 2006 (has links)
This presentation presents results of exposure measurements done in BC grain elevators in 1996 and 2003.
3

Grain and endotoxin exposure monitoring results: Report to HRDC Labour Program

Kennedy, Susan M., Bartlett, Karen H., Keefe, Anya, Ward, Helen, Chan-Yeung, Moira 16 June 1997 (has links)
This report describes the results of the dust and endotoxin sampling carried out in BC grain elevators as part of the Medical Surveillance Program.
4

Exposure in grain elevators: are we measuring the relevant agent? (presentation)

Kennedy, Susan M., Bartlett, Karen H., Dimich-Ward, Helen 06 1900 (has links)
The objectives of this study were to: measure dust, endotoxin and glucan levels; record readily available "determinants of exposure" data; compare exposure levels, determinants of exposure; and evaluate significance of results for future studies and for prevention.
5

Exposure-effect relationships between aircraft noise and road traffic noise exposure at school and reading comprehension: the RANCH Study

Clark, Charlotte, Martin, Rocio, van Kempen, Elise, Alfred, Tamuno, Davies, Hugh W., Head, Jenny, Haines, Mary M., Barrio Lopez, Isabel, Matheson, Mark, Stansfeld, Stephen A. 21 June 2005 (has links)
Transport noise is an increasingly prominent feature of the urban environment, making noise pollution an important environmental public health issue. This paper reports on the 2001–2003 RANCH project, the first cross-national epidemiologic study known to examine exposure-effect relations between aircraft and road traffic noise exposure and reading comprehension. Participants were 2,010 children aged 9–10 years from 89 schools around Amsterdam Schiphol, Madrid Barajas, and London Heathrow airports. Data from the Netherlands, Spain, and the United Kingdom were pooled and analyzed using multilevel modeling. Aircraft noise exposure at school was linearly associated with impaired reading comprehension; the association was maintained after adjustment for socioeconomic variables (ß = –0.008, p = 0.012), aircraft noise annoyance, and other cognitive abilities (episodic memory, working memory, and sustained attention). Aircraft noise exposure at home was highly correlated with aircraft noise exposure at school and demonstrated a similar linear association with impaired reading comprehension. Road traffic noise exposure at school was not associated with reading comprehension in either the absence or the presence of aircraft noise (ß = 0.003, p = 0.509; ß = 0.002, p = 0.540, respectively). Findings were consistent across the three countries, which varied with respect to a range of socioeconomic and environmental variables, thus offering robust evidence of a direct exposure-effect relation between aircraft noise and reading comprehension.
6

A land use regression road map for the Burrard Inlet Area Local Air Quality Study

Brauer, Michael, Henderson, Sarah B., Marshall, Julian 22 December 2006 (has links)
This report includes a road map for developing land use regression models to describe spatial variability of air pollution concentrations within urban areas. Land use regression attempts to better estimate exposure levels for a given population by measuring pollutants at multiple sites specifically selected to capture the complete intra-urban range of its concentrations. Geographic attributes that might be associated with those concentrations are measured around each site in a Geographic Information System (GIS). Typical geographic predictor variables describe site location, surrounding land use, population density, and traffic patterns. Linear regression is used to correlate measured concentrations with the most predictive variables, and the resulting equation can be used to estimate pollutant concentrations anywhere that all of the predictors can be measured. Concentration maps with high spatial resolution can be generated by rendering the regression model in GIS.
7

Studies on organochlorine environmental contaminants with emphasis on analytical methods and occurrence in humans /

Weistrand, Cecilia, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 7 uppsatser.
8

Exchange rate exposure and determinants of exposure in Taiwan electronic industry

Hsieh, Shu-Fan 19 June 2002 (has links)
None
9

Temporal Trends in Satellite-Derived Erythemal UVB and Implications for Ambient Sun Exposure Assessment

Langston, Marvin, Dennis, Leslie, Lynch, Charles, Roe, Denise, Brown, Heidi 10 February 2017 (has links)
Ultraviolet radiation (UVR) has been associated with various health outcomes, including skin cancers, vitamin D insufficiency, and multiple sclerosis. Measurement of UVR has been difficult, traditionally relying on subject recall. We investigated trends in satellite-derived UVB from 1978 to 2014 within the continental United States (US) to inform UVR exposure assessment and determine the potential magnitude of misclassification bias created by ignoring these trends. Monthly UVB data remotely sensed from various NASA satellites were used to investigate changes over time in the United States using linear regression with a harmonic function. Linear regression models for local geographic areas were used to make inferences across the entire study area using a global field significance test. Temporal trends were investigated across all years and separately for each satellite type due to documented differences in UVB estimation. UVB increased from 1978 to 2014 in 48% of local tests. The largest UVB increase was found in Western Nevada (0.145 kJ/m(2) per five-year increment), a total 30-year increase of 0.87 kJ/m(2). This largest change only represented 17% of total ambient exposure for an average January and 2% of an average July in Western Nevada. The observed trends represent cumulative UVB changes of less than a month, which are not relevant when attempting to estimate human exposure. The observation of small trends should be interpreted with caution due to measurement of satellite parameter inputs (ozone and climatological factors) that may impact derived satellite UVR nearly 20% compared to ground level sources. If the observed trends hold, satellite-derived UVB data may reasonably estimate ambient UVB exposures even for outcomes with long latency phases that predate the satellite record.
10

Applying and Evaluating the Two Zone Mathematical Exposure Model in a Paper Coating Operation

Arnold, Susan F. 19 July 2005 (has links)
No description available.

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