Dr. Bennich was the first chairman of ISO TC 213 “Dimensional and geometrical product specifications and verification - GPS,” the technical committee responsible for the standards covered in this book. He held this position from the Technical Committee was started in 1996 to 2008. From 1993 to 1996 he was the Chairman of the precursor to ISO TC 213, ISO/TC 3-10-57/JHG “Joint Harmonization Group” for geometrical product specifications (GPS). He has participated in international standardization since 1980.

Dr. Bennich received a M.Sc. in Mechanical Engineering in 1970 and a Ph.D for a thesis on metal forming in 1975 from the Technical University of Denmark. From 1973 to 1990 Dr. Bennich was the Manager of the Branch for Mechanical Processing of Materials at IPU, the Institute for Product Development, a private consulting company located at the Technical University of Denmark. In 1990 Dr. Bennich started his own consulting business, PB Metrology Consulting, specializing in:

• Engineering metrology, calibration and testing of measuring equipment and products
• Quality assurance of industrial measurement and calibration
• Certification and accreditation
• GPS Dimensioning and tolerancing on engineering drawings.

Dr. Nielsen has been an expert serving on ISO TC 213 “Dimensional and geometrical product specifications and verification - GPS,” and related committees since 1988. He was chairman of ISO TC 213 from 2008 to 2017.

Dr. Nielsen has served as project leader and main author of several ISO standards on subjects such as geometrical tolerancing, surface finish, form, and uncertainty concepts.

Dr. Nielsen received a M.Sc. in Mechanical Engineering in 1984 and a Ph.D. in Metrology in 1988 from the Technical University of Denmark. From 1987 to 1991 he worked as a consulting engineer at IPU, the Institute for Product Development in Copenhagen. From 1991 to 1998 Dr. Nielsen was the Technical Manager of Corporate Standards at Cummins Engine Co. in Columbus, Indiana, USA. Dr. Nielsen started his own consulting business HN Metrology Consulting in 1998.

Prof. Jiang is an active member of ISO TC 213 “Dimensional geometrical product specification and verification – GPS”. She is an expert member of BSI Technical Committee (TDW/4), and is an advice member of China (SAC/TC240). She is a project leader on several ISO standards on surface texture and filtration.

Prof. Jiang has been involved in science research of surface metrology for more than 15 years, following 14 years working in geometrical metrology in the automotive industry. She has published more than 120 papers and 2 co-author books.

Prof. Jiang is a “Yangzi Professor” awarded by the Ministry of Education P.R. China since 1999. She now holds a chair of precision metrology at University of Huddersfield UK and she is also a special professor at Huazhong University of science and technology, China.

Prof. Jiang MSc and PhD works were closely related to the research and development of areal surface measurement instruments and techniques. She received her PhD degree in surface metrology at Huazhong University of science and technology. Her PhD dissertation "Theory and method for measurement of curved surface topography" obtained by the Chinese Government for what was considered the best doctoral dissertation during the 1990s.