System Safety is a discipline which aims to prevent or reduce the incidence of accidents throughout the life of a system by the application of a range of systematic hazard identification, risk analysis and management techniques integrated into the system engineering process.

The discipline emphasises the 'through life' identification of hazards that might lead to accidents and their removal by design whenever practical and, otherwise, their control and mitigation. The hazard identification and analysis is a continuous and iterative process that starts during initial concept and feasibility studies and continues through the specification, design, development, deployment, use and disposal of the system.

Software plays an ever more central role in determining the behaviour of systems and software safety has naturally separated into an important area within system safety, sometimes called software 'system safety'.

Typical concerns of software safety are:
	development techniques to reduce the number of hazardous software failures, including analysis and testing strategies
	protection from the development of an hazardous state into an accident by software monitoring and control.

ERA has considerable experience in undertaking this type of work and offers a range of services encompassing both system and software safety issues.

Key Services
	Developing system and software safety processes
	Developing and evaluating safety requirement specifications
	Validating safety requirements
	Conducting:
	System Hazard Analysis (SHA)
	Sub System Hazard Analysis (SSHA)
	Software Hazard Analysis
	Software Fault Tree Analysis (SFTA)
	Identifying safety functions and allocating SILs
	Requirements tracking
	Developing software test schedules
	Performing software testing
	Undertaking independent safety assessments
	Developing software safety arguments for inclusion in safety cases
	Developing and validating formal specifications and proving safety properties
	Managing hazard logs
	Managing and conduction formal safety reviews
	Performing quality and safety audits
	Providing procurement assistance

Experience
Use of standards and guidelines such as:
	Def Stan 00-56			RTCA DO-178B
	Def Stan 00-55			IEC 61508
	Def Stan 00-54			IEC 61511
	Def Stan 00-58			MIL STD 882 B, C & D
	EN 50126			The MISRA Guidelines
	EN 50128			The Yellow Book
	EN 50129