An industry viewpoint of conformity assessment with reference to CASS. (Conformity Assessment of Safety Systems)

The development of the CASS scheme arose from a series of programmes supported by both the Department of Trade & Industry (DTI) and the Health and Safety Executive (HSE) over the last twenty years. Since the mid 1980s industry has placed increasing reliance on programmable safety-related systems, but at the same time concerns have been expressed about the risks arising from the increasing use of such programmable systems. An all-sector working party (associated with a DTI sponsored IEE-BCS study) recommended deferring certification pending more research. It also recommended support for the development of IEC61508, Functional Safety: Safety Related Systems, in order to establish and harmonize best practice across sectors. The CASS project, which commenced in 1998, was supported by the DTI under its Sector Challenge Programme. The project secured strong support from industry, including all the major UK trade associations, professional institutions, and the HSE. This project delivered the CASS conformity assessment scheme for safety-related systems based on the international standard IEC 61508. Its aims are to facilitate the opening of markets, to improve UK competitiveness, to reduce the cost of compliance, and to improve safety and professional and public confidence in safety. The presentation charts some of the history of the CASS scheme, and outlines the principles which underpin the structure of the conformance assessment offered under the scheme. Against that background, the author traces the history of his company's involvement with CASS and the related activities, and explores the business driving factors which motivated that involvement-and that of the GAMBICA team working on CASS-in seeking to establish with others a conformance assessment scheme which aligned with their commercial priorities whilst still being applicable to other supply-chain models. The primary goals set at the beginning of the CASS project have either all been realised, or the route to achieving them has been firmly established, and the long-term view is that the involvement with the evolution of CASS will prove to be fully justified.