Thesis (MTech (Chemical Engineering))--Peninsula Technikon, Cape Town, 2004 / 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 data sets.

Submitted in partial fulfillment of the requirements for the degree of Masters in Technology: Business Administration, Durban University of Technology, 2007. / Unsafe incidents are a regular occurrence in the chemical industries, which have resulted, in some cases in the catastrophic destruction to the environment and loss of life. Major global organizations have shut down after experiencing fatal unsafe incidents as in the case of Union Carbide. This organization was closed after the Bhopal incident in India, in 1984, which claimed the lives of a-bout three thousand residents (see appendix d). In this study, the safety and operational risks at a selected chemical company in Durban are researched. This study looks at the huge number of unsafe incidents in a three year period, from (2003) to year (2005), that occurred at this organization. The objective of this study is to identify the variables that contribute to the high number of unsafe incidents within the organisation. The study will focus on the relationship between staff perceptions and management's assumptions of these contributory variables. The sub-objectives of the study are: o To ascertain staff perceptions of the contributors to the incidents and unsafe working conditions; o To determine if management is accurate in their assumptions of the causes for the incidents; and o To determine relationships between staff perceptions and actual causes of the incidents. The contributors were themed in the study in the following manner: o Behaviour and attitude; e Communications; e Plant and equipment; e Training and development; o Planning and workload; o Safety aspects; and e Other related aspects. Implementing the recommendations made will assist in reducing the number of unsafe incidents and make the organization a safer place for all stakeholders. / M