ISO 17635 gives guidelines for the choice of non-destructive testing (NDT) methods for welds in metals. It also guides the evaluation of the results for quality control purposes, based on quality requirements, material, weld thickness, welding process and extent of testing.
ISO 17635 also specifies general rules and standards to be applied to the different types of testing, for the selection of the method, the techniques and the acceptance levels. Acceptance levels cannot be a direct interpretation of the quality levels defined in ISO 5817 or ISO 10042. They are linked to the overall quality of the produced batch of welds.
The requirements specified in ISO 17635 for acceptance levels for NDT conform with quality levels stated in ISO 5817 or ISO 10042 (moderate, intermediate, stringent) only on a general basis and not in detail for each indication.
— Annex A gives correlations between quality levels, testing levels and acceptance levels for specific testing techniques.
— Annex B gives an overview on specific testing techniques of standards linked to quality levels, acceptance levels and testing methods.
ISO 17635:2025 text has been approved in Europe as EN ISO 17635:2025 without any changes.
