Allan Rogerson joined the United Kingdom Atomic Energy Authority in 1975 working on the effects on neutron irradiation on the dimensional stability of zirconium alloys and began research into ultrasonic techniques for detecting and sizing defects in PWR pressure vessels in 1979.

He participated in the UKAEA Defect Detection Trials and PISC II trials from 1980-84 and co-authored the NDT Chapter of the 1982 Light Water Reactor Study Group Report on the Integrity of PWR Pressure Vessels in 1982, which introduced the concept of inspection validation/qualification. 

From 1984-89, he led teams developing improved NDT techniques for other PWR primary and secondary circuit components at the Sizewell B PWR, performing inspection reliability studies and participating in the PISC III trials. Subsequently, with AEA Technology and then Serco Technical Consulting Services, he has provided NDT consultancy on UK government and CEC technical assistance projects in FSU countries, Russia and China. Most recently, in 2009-2011 he led Inspection Qualification projects conducted by the UK Inspection Validation Centre in China. He currently sits as an industrial member on the board of the UK University Research Centre on NDE.

Presentation Title:

 A personal perspective on the early developments in inspection qualification and reliability assessment in the UK nuclear industry

Inspection Qualification in the nuclear industry has its origins in the recommendations made in the 2nd Light Water Reactor Study Group report on PWR pressure vessel integrity published in 1982, international round robin inspection exercises performed in the 1970’s to early 90’s, and the early work of the UK Inspection Validation Centre. Considered an interim measure initially, introduced to provide timely evidence on inspection capability until quantitative measures of inspection reliability could be derived, Inspection Qualification has now been adopted in many countries throughout the world nuclear industry based on either the ENIQ methodology or the Performance Demonstration requirements specified in the ASME Code Section XI, Appendices VII and VIII.

Assigning meaningful quantitative measures to overall inspection reliability and Probability of Detection has remained an elusive goal since the 1970’s. Understanding of the factors influencing inspection reliability, based on practical inspection reliability studies, theoretical modelling developments and accumulated evidence from experimental trials is now considerable. However, the ultimate goal has not been achieved, leaving inspection qualification as still the preferred approach to providing confidence in inspection capability and reliability.

Adoption of Inspection Qualification outside the nuclear industry has been slow due to understandable concerns regarding its cost implications. However, there is evidence that forms of inspection qualification are gradually being adopted for specific high importance inspection applications in the oil and gas, aerospace and other industries.

This paper provides a personal perspective on the early developments in inspection qualification and reliability assessment, based on the author's participation in these developments in the UK nuclear industry, and a snapshot of the broader adoption of inspection qualification across various industries worldwide.