Skip to main content
Taxation and Customs Union

Action 2 - Inter-comparisons and method validations

The main objective of CLEN Action 2 is to ensure a uniform application of the control of goods in the European Union through the harmonisation and validation of methods used by customs laboratories.

European customs laboratories participate therefore in Proficiency Testing Schemes to assess their own performances and efficiency, as well as to confirm that the results they obtain are similar to those of other laboratories. Participation is also essential to achieve accreditation, which is a guarantee of quality for laboratories. For instance, laboratories may be accredited according to ISO 17025, which is an international standard guaranteeing laboratories’ competence of testing.

The design of each Proficiency Testing Scheme depends on its purpose, i.e. whether the aim is:

  • to carry out collaborative trials for the validation of a specific method,
  • to carry out a comparison of different methods or analytical protocols used to measure the same parameter,
  • to assess laboratories’ performance.

Preparation of the studies and their results are discussed in meetings of the ad-hoc working group of volunteer participants for each study.

Proficiency tests and ring tests organised within the CLEN usually:

  • gather between 10 and 50 participating laboratories,
  • deal with 2 to 10 samples, and
  • are carried out on 1 to 20 different parameters for each sample.

Here are a few examples of tests that have been organized over the past few years:

Ring test on ceramics and pottery

Proficiency test related to Meursing table

Ring test on milk products

Proficiency test on mineral oils

Ring test on nuts and seeds

Proficiency test on pet-food

Proficiency test on rice

Inter-laboratory test on BPE Euromarker

Proficiency test on spirits, alcoholic beverages and alcohol-based preparations

Proficiency test on sugars and sugar containing products

Proficiency test on Textiles

Proficiency test on Tobacco

Ring Test on Cannabinoids