background: chemical contaminants present in the work environments include gases, vapors, and solid and liquid suspended particles. the number of factories producing chemicals has increased significantly. each year, new products are introduced into the market. consequently, the number of employees at risk of exposure to these materials is increased. hazardous chemicals are used in the petrochem...

OBJECTIVES To assess the association between petrochemical exposure and spontaneous abortion, a retrospective epidemiological study in a large petrochemical complex in Beijing, China was conducted. METHODS Plant employment records identified 3105 women who were married, were 20-44 years of age, and had never smoked. Of those, 3070 women (98.8%) reported at least one pregnancy. From this group...

A new method for optimising process networks is presented in this paper. The method uses economic analysis of existing systems based on the value analysis method derived by Sadhukhan (2002) as the basis to derive the optimum network design. Optimising a large scale industrial system (e.g. refineries, petrochemicals) where multiple processes, many material streams and a number of supporting syst...