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Standards and Guidelines

Adelard has extensive experience of the formulation of policy and the development of standards concerning the application of computers to areas where consideration of reliability and safety are paramount, including working on Defence Standards 00-55, 00-56, 00-58 and 00-42 Part 2 for the UK MoD. Other clients include the HSE, the DTI, the CEC and BNFL.

We provided HSE/DTI with consultancy on the design of what has become IEC 61508 and the technical directory in the standard is heavily based on the book edited by Peter Bishop of Adelard.

We are also actively involved with the development of standards for civil Air Traffic Services equipment. We are a member of the industry consultative group on the development of CAP 670.

We were a member of the authoring committee for Issue 3 of Def Stan 00-56.

We can also offer general support for the process and technical aspects of standards and document production.

For further details about our work within Standards & Guides, check the links below:

Justifying the use of SOUP in Safety Related Applications
 The UK Health and Safety Executive recently commissioned research from Adelard into how pre-existing software components may be safely used in safety-related programmable electronic systems in a way that complies with the IEC 61508 standard. In the proposed approach, the safety assurance of SOUP is based on a documented, five-phase safety justification (or safety case) that sets out the safety claims for the system, and the evidence and arguments that support them. This can be linked with the key development stages identified in IEC 61508.

The choices made at the architectural design phase have a major impact on the safety assurance of systems containing SOUP. A "design for assurance" approach is recommended where the risks posed by the architectural components including SOUP are determined and methods for limiting hazards identified (such as the use of barriers and "wrappers") together with outline safety arguments and evidence. The safety justification and implementation costs can then be optimised.

Guidance is provided on the supporting evidence including an evidence profile for SOUP that may be re-used for different safety justifications. The reports suggest criteria for deciding when black box evidence is sufficient, when additional white box evidence is required, and how the evidence requirements change with safety integrity level (SIL). Finally, the reports consider long-term management of safety-related SOUP for a single safety system and for multiple systems within the same organisation. The research is published as two reports available from the HSE Website. Further information and links to download the SOUP reports.

Def Stan 00-56: Safety Management
 We were a member of the authoring committee for the new Issue 3 of Def Stan 00-56. The new version is major departure from the previous issue in that it is a goal-based standard. Def Stan 00-56 Issue 3 incorporates the old Def Stans 00-54, 00-55 and 00-58. This standard can be downloaded from the DStan Website.

We have been involved with this standard since we wrote Interim Def Stan 00-56, which set out a systematic process for the safety analysis of defence equipment, and Interim Def Stan 00-55, on the procurement of safety-critical software. Def Stan 00-56 was the first published standard to address the safety analysis of design faults in software. Since then, we have been involved with the application and interpretation of these standards on numerous projects.

We provide a course on Def Stan 00-56 Issue 3.

Def Stan 00-42 (Part 2): Software Reliability
 This standard provides guidance on the achievement of software reliability. A particular feature is the central role of the Software Reliability Plan and the Software Reliability Case, which we developed by generalising our work on safety cases and making it appropriate to lower reliability targets. We also drew on our research on software reliability. This standard can be downloaded from the DStan Website.

Interim Def Stan 00-58: Hazard and Operability Studies
 We carried out research to support the development of Interim Defence Standard 00-58 on software Hazard and Operability Studies. This work included carrying out video analysis of actual Hazops sessions.

We also defined a very general reference model for describing systems and representing their hazards, based on ideas from object-oriented programming, and developed a hazard identification method built around this reference model. This work subsequently fed into recent tools and studies on the quality and effectiveness of hazard identification techniques.

This standard can be downloaded from the DStan Website.

JSP 318B: Regulation of Ministry of Defence Aircraft
 Adelard was awarded the contract to produce the fourth edition of Joint Service Publication (JSP) 318B, on the regulation of UK military aircraft. The work involved defining a safety management system for airworthiness and fitting the existing arrangements into this framework. The publication is now known as JSP 553.

We were awarded a follow-on contract to produce guidelines for the application of the ALARP Principle to safety targets for military aircraft. This work was published by ADRP (part of DPA's Air/Land Technology Group) in January 2005.

CAP670
 Adelard has been closely involved with the development of the regulatory approach to Air Traffic Systems (ATS). We have worked with the CAA Safety Regulation Group to develop SW01 "Requirements for Software Safety Assurance in Safety Related ATS Equipment" that form part of CAP670.

The document provides a regulator's viewpoint on the evidence required for assurance and has a similar technical basis to ASCAD. It introduces the concept of Assurance Evidence Level (AEL) to relate the criticality of the software safety requirement to the depth and strength of evidence that is required.

Guidance for MoD Projects
The industrial application of safety management and analysis systems as required by Defence Standard 00-56 and IEC 61508 will often be done within a process that is certified to ISO 9001. We have produced a guide for the UK MoD containing practical advice on how to implement these safety requirements within such a quality system. The guide also contains general tutorial material on, for example, setting safety targets, safety analysis techniques, and design heuristics for safe systems. This guide was developed in response to industry needs for the application of Defence Standard 00-56.

We have also produced guides for MoD Project Managers on: the management of projects involving safety critical software; Programmable Logic Controllers (PLCs) in safety related applications; achieving software reliability; and software languages for safety related applications. We have also prepared a study paper on the assurance of commercial off-the-shelf (COTS) software

Guide for Virtual Instruments
 We developed a Best Practice Guide on the Development of Virtual Instruments for the UK Department of Trade and Industry.

Ewics TC7
 We are active in the European Workshop on Industrial Computer Systems (Ewics), a long-standing European group producing guidance on safety related PES.

As well as contributing to international standards such as IEC 880 and IEC 61508, Ewics has published three volumes on the Dependability of Critical Computer Systems, published by Elsevier Applied Science, and will shortly be publishing guidelines on formal methods, security, project management, PLCs and distributed systems. We were one of the main authors of the formal methods guidelines and these are available for download on the Ewics site.

Standardisation and documentation support
 Its long-term interest in standards development allows Adelard to offer general support services for standards development.
  • Process improvement and standards
    • We have applied the process evaluation module from Reaims to the standards-making process itself, which can be seen as a form of requirements engineering. This has enabled us to understand the complexities of standards-making better, and to suggest possible improvements to standards bodies. A paper based on this experience is available here.

  • Claviar document support tools
    • The development of standards and guidelines is a lengthy process with numerous reviews and meetings. Standards such as IEC 61508 have taken over ten years to develop. In addition, once standards are deployed, it is necessary to adapt them in the light of experience, or to interpret them for a given operating context.

    To support this process, Adelard has developed the Claviar toolset which can permit documents to be published and reviewed over a corporate intranet, or the Internet using standard Web browsers.

  • Document production and publication
    • The final production and publication of complex documents in camera-ready or electronic form is a skilled and time-consuming process. We can help with the production of HTML and PDF documents and webs, and publication in paper or electronic formats.