For strategic chemicals management in process design, the chemical risk and environmental impact due to the use of chemicals must be identified and controlled. Although various scientific methodologies evaluating such issues have been developed, a single application of one of the methodologies cannot address all of the adverse effects. In this paper, we classify chemical risks using suitable scientific assessment methodologies for risk trade-off analysis on the basis of the features of adverse effects. On the basis of this classification, current problems can be identified through the understanding of differences in the existing chemical risk and environmental impact. An actual case study of agent selection in metal-cleaning process design has been performed. It is thereby demonstrated that risk trade-off among agents can be visualized to distinguish agents. In appropriate agent selection, all adverse effects associated with the use of chemicals can be considered with such a visualized risk trade-off. Risk trade-off analysis based on the classification of risk enables the identification of increased and decreased risk upon substituting chemicals and processes. This analysis can be used as a foundation for the discussion of practical strategies on chemicals management in process design.