The method validation study is carried out in 2 phases, according to the current technical protocol, based on EN ISO 16140.

The objective of the first phase (preliminary study) is to characterise the method and assess its effectiveness by comparing it to the effectiveness of the standardised reference method. This is carried out at the expert laboratory. The diversity of samples tested and the experimental conditions applicable to the study (sufficient number of naturally contaminated samples, application of specific stress protocols for artificial contamination,…) allow the method to be tested under conditions that are close to the real conditions in the field.

The objective of the second phase (or inter-laboratory study) is to compare the efficacy of the method to be validated and the reference method in several laboratories (8 to 10 minimum) under defined conditions of reproducibility and repeatability.

By combining the results of the 2 phases of the study, it is possible to reach a decision on all of the performance criteria of the method as described in EN ISO 16140.

For the purposes of the AFNOR VALIDATION mark, the technical board has chosen to go further than EN ISO 16140 on certain criteria considered critical such as the diversity of samples tested or the confirmation of positive results, for example.

At the same time, AFNOR Certification evaluates the quality assurance procedures on the production site of the method to be validated in order to check their effectiveness.

Periodical monitoring
AFNOR Certification carries out regular monitoring in order to check and guarantee users that validated methods comply at all times with the requirements of the AFNOR VALIDATION mark.