www.ceees.org - for product life and performance

Publication N 9 - Reliability - For A Mature Product From The Beginning Of Useful Life. The Different Type Of Tests And Their Impact On Product Reliability. ISSN 1104-6341


The challenges to which industry are confronted requires consideration of innovative design, technologies and conditions of use. Historically the reliability or maturation of products could only be established an improved experimentally, either by tests during the development or during the operational deployment. The risks associated with the second approach are unacceptable to the ultimate users who demand a reliable product. They are also equally unacceptable to the equipment supplier because of the detrimental impact on the suppliers image as well as the associated costs unreliable products can cause.

This document presents Recommended Practices, which represent the current best approaches for building product reliability and maturation during product development. The document highlights the role of experimental testing in this growth of maturation.

The present Recommended Practice, has been elaborated by the CEEES R&ESS TAB during meetings held in many towns throughout Europe allowing the participation of a wide range of specialists. These specialist encompass a range of expertises and experience of many industries. Its content represents the current best practices in matter of building the product maturation during the development with highlighting the vision of the role of experimental testing in this maturation growth.



The product life profile

The product technical specification

The parts (or components) engineering

The performance-based requirement in design

The elimination of weakness in design and technologies

Uncertainty and test factors

  • Environment Variability
  • Equipment Strength Variability
  • Ageing of Equipment
  • The Purpose of Uncertainty Factor
  • The Purpose of Test Factor

validation of the functions0

environmental stress screening and ha-ess



ANNEX 1 - Types Of Reliability Tests

ANNEX 2 - Frequently Asked Questions on Reliability Test Types

ANNEX 3 - Feasibility Test

ANNEX 4 - Comparison of ESS and HA-ESS

ANNEX 5 - Definition Of Terms

CEEES is a confederation of the environmental engineering societies of

the United Kingdom (SEE),
France (ASTE),
Germany (GUS),
Sweden (SEES),
Switzerland (SSEE),
Finland (KOTEL),
Belgium (BSMEE),
the Netherlands (PLOT),
Italy (AITPA),
Czech Republic (NACEI)
Austria (ÖGUS)
Portugal (SOPSAR)