Instructor

Donald G. Firesmith, Software Engineering Institute, dgf@sei.cmu.edu

Abstract

Although inadequate requirements are a primary cause of accidents involving software-intensive systems, there is insufficient interaction between requirements and safety engineering and insufficient collaboration between requirements and safety teams. Requirements engineers know little about safety, and safety engineers know little about requirements. Safety engineering concentrates on architectures and designs rather than requirements because hazard analysis typically depends on the identification of components, the failure of which can cause accidents. The resulting safety-related requirements are often ambiguous, incomplete, and even missing.

To address this problem, this tutorial uses a realistic example to teach 1) requirements engineering to safety engineers, 2) safety engineering to requirements engineers, and 3) an integrated method for engineering the four major types of safety-related requirements: (a) safety requirements (a form of quality requirement), (b) safety-significant requirements (including safety-critical functional, data, interface, and non-safety quality requirements), (c) requirements for safety subsystems, and (d) safety constraints (e.g., mandated safeguards). This tutorial introduces a taxonomy of safety engineering concepts including valuable assets that can be accidentally harmed, safety events such as accidents and incidents, hazards, safety risks based on harm severities and likelihood of hazards/accidents, safety integrity levels (SILs) of requirements, and safety assurance evidence levels (SEALs) of associated components.

Biography

Donald G. Firesmith is a senior member of the technical staff at the Software Engineering Institute (SEI), where helps the US DoD acquire large complex software-intensive systems of systems. With over 25 years of industry experience, he has published 5 software engineering books. He has a regular column on requirements engineering in the Journal of Object Technology (www.jot.fm). He has also published dozens of articles and spoken at numerous conferences (www.donald-firesmith.com/Firesmith/Articles.html) as well as been the program chair or on the program committee of several international conferences. He has taught several hundred courses in industry and numerous tutorials at conferences in the areas of object technology, requirements engineering, method engineering, testing, and program management. He is the founding chair of the OPEN Process Framework Repository Organization www.opfro.com, and the developer of its repository of over 1,100 free, open-source, reusable method components for constructing both system and software development methods.