Dependability, a key factor to the quality of products: IEC 300 series and ISO 9000 series standards.

Introduction

The approach that a successful and competitive business can be run on a free market only if permanent care is taken of the quality of products, leads to the introduction of the total quality concept, based on the corresponding quality system and the application of the ISO 9000 series of standards. In essence, the activities are directed towards quality assurance, quality management and continuous quality improvement. On the other hand, the concept of dependability has, for a long time, found its place in the military and associated industries and also in the special high technology industries such as aircraft, nuclear, and chemical industries and in telecommunications and fast rail-transport services. In these industrial areas, the significance of reliability, availability, and safety of products has long been recognized. Understanding the significance of this concept for attaining a required level of quality, not only of products but also of production systems and processes, invoked considerations for introducing the dependability concept into other industries and services (including systems for the mass production of consumer goods) and promoted the co-operation of the IEC and ISO organizations. For this reason, it appears necessary to correlate dependability assurance, dependability management, and permanent dependability improvement to the quality-oriented activities[1,2].

The need to establish a correlation between the areas of dependability and quality has been present for some time because the two areas had been treated separately, sometimes mutually inconsistently. Relatively recently, through general acceptance of the concept of total quality, the foundations have been laid down for a unified approach to formulating (and solving) problems in these two areas. At present, the two areas are often refered to as closely related and complementary, legally identifiable through the corresponding series of standards, IEC 300 and ISO 9000, which have dual structures and complementary contents.

In order to understand fully the essence and significance of the concept of dependability and its interrelation to the concept of quality, as well as the relation between the corresponding series of standards, a reappraisal of the dependability concept and of the basic assumptions resulting in a unique determination of this concept is due. This, first of all, requires a detailed determination of the concept of a product with all its attributes and its relations to all subjects involved: supplier (producer, distributor, importer, assembler, or service organization) and customer (purchaser, ultimate consumer/user, or beneficiary).

Product and product attributes

Until quite recently, the concept of a product in practice has been used in its narrow sense to denote a physically tangible piece of hardware. In order to cover other results of the work put into effect, such as software or services, ISO 8402[3] introduced a generalized concept of a product as: the result of certain activity or process. In the notes supporting this definition it is stated that a product implies: hardware, software, processed material, and service; that it could be tangible (hardware, processed material) or intangible (information, concepts) or a combination thereof. The listed classes of products constitute generic categories such that any product could be classified to belong either to one of the categories or to be a combination of some of them. A classification of products based on type of results of the work put into effect in different industrial/economic sectors is also …