Comparing ISOs with ISOs
16/08/2013
John Moody, Technical Support Engineer at BINDT, discusses whether the ‘ISO 9712 Standard’ (to use the term by which it is often known) gives the client the confidence that the certification scheme used to qualify NDT inspectors is applied equally around the world and that the inspection is performed in a competent manner.Firstly, the specific issue of which ISO 9712 is in use needs to be ascertained. The current issue is ISO 9712:2012, but not all certification schemes are using this. Earlier editions have allowed certification examinations to be only theory-based, with no practical examination part, and there may be schemes that are still using this format.*
With ISO 9712:2012, will the certification scheme be in compliance with the published criteria without any deviation? A certification body can, by using Guide 21, deviate from the criteria given in the standard and this can be significant. The certification can then still be in accordance with ISO 9712:2012, but in reality there could be considerable differences.
One of the documents referenced in ISO 9712:2012 is TR 25107, which is a guideline for the syllabuses; this technical report tries to encompass many topics but does not follow the format in ISO 9712:2012. The syllabuses are not broken down into General Theory, Specific Theory and Practical at Levels 1 and 2, the Level 3 basic examination parts A, B and C are not defined and neither are the Level 3 main method parts D, E and F. Within ISO 9712:2012 there are guidelines for marking schemes, instruction writing and procedure writing; these are not referenced in TR 25107. TR 25107 does not refer users to the country-specific regulations for radiation safety.
Within the UK, industry has required that certification meets its needs and, as a consequence, for example, to gain ultrasonic certification in weld, cast or wrought products there would be a need to pass three separate examinations. ISO 9712:2012 encompasses all the product sectors into one examination and the practical involves fewer samples. UK certification also has separate certification in ultrasonic phased array, guided wave and time-of-flight diffraction. Industry within the UK is also looking at the in-service inspection needs and is considering additional certification to cover this, as the degradation processes can be very product-specific and industry-related, creating a need for very specific certification. Inspection equipment is constantly evolving and its capabilities are improving. Phased array probes in ultrasonic and eddy current testing are examples that are becoming commonplace, especially as the signal data can be processed and stored efficiently.
In conclusion, the client needs to be aware of what exactly is being offered as certification under the heading of ISO 9712, as there are many and varied approaches being adopted. Two different schemes can have significantly different criteria and yet still rightfully claim to be in compliance with ISO 9712.
*Editor’s note: Certification according to ISO 9712:2005 (and/or EN 473:2008) awarded before the publication of ISO 9712:2012 remains valid until the next mandatory step in the certification process, ie renewal on recertification, which shall be carried out according to ISO 9712:2012.
Note: The views expressed in this article are those of the author and are not necessarily those of The British Institute of NDT. The British Institute of NDT does not guarantee the completeness, timeliness or accuracy of the information presented and shall not be liable for any loss or injury arising from its publication. Healthy discussion is encouraged and letters should be emailed to ndtnews@bindt.org
