Software Safety

Software Safety

Introduction

The Software Safety course will provide delegates with a general appreciation of software safety engineering issues in the context of a typical systems development life-cycle. The Software Safety Course has been developed to raise awareness of software safety issues and to promote safety culture as required by any Safety Management System.

As well as some theoretical material, the course provides practical examples of how programmers could improve software safety throughout the software development life-cycle.

Session 1 - Introduction to Safety (60 min)

• TO 1.1 Need for Safety Explain the need for formal safety management.
• TO 1.2 Functional Safety Explain the difference between health & safety and functional safety.
• TO 1.3 Systems and Software Describe how software safety fits into a systems context using a representative system as an example.
• TO 1.4 Safety Management Explain how an Safety Management System is implemented and documented in a Safety Management Manual.

Session 2 - Software Systems Safety (60 min)

• TO 2.1 Safety Terminology Give a definition for some basic safety terminology including: safety, risk, error, fault, random failure, systematic failure and hazard.
• TO 2.2 Safety Standards List some of the important safety standards relevant to systems and specifically to safetyrelated software development.
• TO 2.3 Safety Analysis Describe a typical safety life-cycle and the associated system Safety Analysis methods and objectives.
• TO 2.4 Safety Requirements Explain how system and software safety requirements are specified for safety-related systems.

Session 3 -Safety Requirements Exercise (60 min)

• TO 3.1 Exercise Complete an exercise to assess, review and specify system and software safety requirements for an example aircraft wheel braking system.

Session 4 - Software Safety Assurance (90 min)

• TO 4.1 Safety Management Describe the typical contents of a Safety Management Manual and explain the safety processes and responsibilities detailed therein.
• TO 4.2 Safety Cases Explain what a safety case is and why it is required. Explain the scope and purpose of a Design Safety Case (DSC) and describe the relationship between a DSC and an Operational Safety Case. Explain what a Software Safety Analysis (SSA) is and explain the differences between an SSA and a DSC.
• TO 4.3 Safety Argument Describe the constituent parts of a safety argument and explain Goal Structuring Notation.
• TO 4.4 Software Safety Evidence Describe the different types of process-based and product-based evidence required to make a software safety argument and explain how this evidence can be generated throughout the SDLC.

Session 5 - Programming for Safety (60 min)

• TO 5.1 Real-Time Issues Identify the typical real-time software issues that can adversely impact upon the safety of a system.
• TO 5.2 Partitioning & Redundancy Explain how partitioning and logical and physical software partitioning can maintain the integrity of a software system.
• TO 5.3 Defensive Programming Explain some popular defensive programming techniques and discuss software reuse and the use of Commercial-Off-The-Shelf (COTS) software within this context.
• TO 5.4 Languages & Safe subsets Compare the use of Ada, C, C++ and Java programming languages for safety-related systems and describe the purpose of safe subsets.
• TO 5.5 Firmware Explain a basic process for the safety assurance of firmware devices containing code with the potential for systematic failures.