Safety Checklist for Four-Variable Requirements Methods
Guy Helmer · 1998
This paper organizes safety criteria, as given by Leveson, Jaffe, Heimdahl, Melhart, and Lutz, as a safety checklist for use on four-variable requirements models for real-time process-control systems. Special attention is given to the Software Productivity Consortium CoRE and Naval Research Laboratory SCR requirements specifications built on the four-variable model. The criteria are presented in English text and may be applied during the requirements engineering phase of software development to reduce safety-related software errors. 1 Introduction This document organizes and applies the safety criteria defined by Software Requirements Analysis for RealTime Process-Control Systems [3], Targeting Safety-Related Errors During Software Requirements Analysis [5] and Leveson's book Safeware [4] to four-variable models such as that used by Software Cost Reduction (SCR) [2] and the Software Productivity Consortium's CoRE [1]. 1.1 Four-Variable Model The four-variable model was defined by Pa...