The Cape Peninsula University of Technology (CPUT) Electronic Theses and Dissertations (ETD) repository holds full-text theses and dissertations submitted for higher degrees at the University (including submissions from former Cape Technikon and Peninsula Technikon).
The use of Monte Carlo simulation to quantify the uncertainty in modeled estimates of toxic, radiation and overpressure impacts resulting from accidents in large chemical plants
Current Risk Assessment procedures for the estimation of the acute health impacts
resulting from the accidental release of toxic chemicals into the atmosphere involve the
definition or construction of a representative accidental release scenario and the use of
one or other air quality or dispersion model to estimate ambient air concentrations and
exposure durations in the vicinity of the source. Legislation such as the South African
Occupational Health and Safety Act, 1993, Major Hazard Installation Regulations,
United States Risk Management Plan Rule and the European Union Seveso n, to prevent
and or minimize impacts of such events require owners of installations to perform a Risk
Assessment if they handle hazardous substances above specified threshold quantities.
Mathematical modeling has been widely used to assist with the Exposure Assessment to
perform off-site worst-case release analysis. Governmental departments, agencies and
local authorities increasingly (but not exclusively) rely on air pollution models for
making decisions related to air quality, traffic management, urban planning, and public
health. As a result, the model users' community is becoming larger and more diverse.
Most of the air quality modeling work has so far been based on the "deterministic"
approach of using only set input parameters and specific applications. The selected model
provides estimates of averaged concentrations using specific meteorological and emission