Reliability in product design-specification of dependability requirements

This paper presents a systematic approach to specifying dependability requirements for a product and system. Vague requirements and specifications cause the most waste in the design process and lengthen the product design time. With the method presented here, quantitative requirements of dependability that guide product design and development work can be specified. The specification is carried out based on customer requirements and the design team's knowledge. The method can be applied both to tailor-made business-to-business products and to ordinary consumer goods. With the method, dependability requirements can be allocated to the functions, systems, mechanisms and parts as to the design work proceeds and design concepts are known. Allocation is based on the object's technical complexity and importance as set by the customers. With the method, the effect of dependability requirements set by the customer to the known technical solution of a product can be demonstrated. This connection is important in order to avoid promising something that can not be achieved or its achievement will come too expensive.