The Use of Risk-Based Approaches in Post-Construction Standards

Abstract

This article provides a general discussion on the application of risk analysis in the development of safety codes and standards, with particular emphasis on the standards currently under development by the ASME Post-Construction Committee. It also provides an exposition of some of the implicit risk-based assumptions incorporated in the basic new construction pressure vessel code (ASME Section VIII, Div. 1). It proceeds to argue that codes and technical safety standards should be developed using explicit rather than implicit risk-based principles. The authors argue that, contrary to popular belief, pressure equipment standards have always incorporated ad hoc, anecdotal risk principles. The article elucidates this through two detailed examples dealing with provisions affecting nearly all vessels produced to Section VIII, Div. 1: i.e., joint efficiency factors and the scope of coverage of the code. The article then proceeds to a discussion of data collection and cost-benefit modeling which would support a migration to a more rigorous risk-based foundation for future code development. The authors argue that the interests of the entire community of code users—users, manufacturers, regulatory authorities, insurers, and the general public—will be better served by the rational incorporation of risk principles as a foundation for code development. Examples of the application of risk-based approaches in two of the Post-Construction Code drafts follow. [S0094-9930(00)02003-5]