An Introduction to the Safety Standard IEC 615081

The development of a generic international standard on achieving safety of systems based on programmable electronics has been in train for several years. A draft, published in 1995 and referred to as 'IEC 1508', presented the principles embodied in the document, with the result that they began to be influential in sector-specific standards and on the way of thinking about safety. Now IEC 61508, published in 1998, appears to be close to the final document. This paper explains the standard, what it sets out to achieve, and the principles on which it is based.