Abstract. 2007 marks the publication of the latest edition of SNT-TC-1A[1]. It is now 40 years since the issue of the first edition and this paper will take a brief look at the development of the employer based certification programme and consider the differences between the various editions published over the past 40 years.
Throughout the presentation reference will be made to the importance of the employer and the development of a Written Practice which meets his needs; there will also be information on the relationship between the employer and Level 3.
The presentation will also take a look at some of the issues which have arisen over the years relating to the employer based certification.
Finally consideration is given to how other NDT operator certification schemes (such as EN4179[2] EN 473[3] and ISO 9712[4]) deal with the relationship between the employer and the NDT operator and how much each system owes to SNT-TC-1A.