CUNA is a non-profit association federated to UNI (Italian National Standardization Body). CUNA is in charge for representing the national stakeholders in CEN and ISO standardization organization on several fields related to automotive sector. CUNA also contributes to finding appropriate solutions for the quality-related topics in the automotive sector and organizes proficiency testing since more than 30 years to help stakeholders to improve their quality management.

Proficiency Testing (PT) is the most common type of interlaboratory comparison. Participation in proficiency testing schemes gives the participating laboratory the opportunity to assess the effectiveness of its performance on the measurement and data production process and whether any corrective actions need to be implemented.

CUNA, as third-party entity, is an aggregator of laboratories (into GL3 working group) and the organiser of the PT schemes according to EN ISO/IEC 17043 “General requirements for the competence of proficiency testing providers” guidelines, based on: scheme organisation, statistical data processing and performance evaluation, disclosure and confidentiality policy.

GL3 is a working group of laboratories and stakeholders in the field of emissions and fuel consumption from chassis dynamometer vehicle tests. Its aim is to enhance the quality of measurements by means of interaction and participation to proficiency testing schemes. GL3 meetings are organized twice per year in order to give the possibility to its members of an effective sharing of information and best practices. In those meetings the final reports of proficiency testing are also presented by CUNA.

The continuous evolution of Regulations in the exhaust emissions sector leads the laboratories to a continuous comparison and updating of the instruments and test procedures adopted in the PT schemes. Laboratories can monitor their performances on the measurements on emissions and fuel consumption with motorcycles, petrol and diesel cars, hybrid and electric vehicles over the years. PT are also organised with technical gas mixtures used in laboratories as calibration gases for the measuring instruments.

Tests in PT are carried out by the laboratories according to a known and shared test protocol. The statistical processing of participants' data is based on robust statistical methods that minimise the influence of outliers. The evaluation of the analytical performance of the participating laboratories is given with z-score statistical performance indicators.

Proficiency Testing (PT) is an external quality control tool recommended by EN ISO/IEC 17025 “General requirements for the competence of testing and calibration laboratories” and by accreditation bodies to demonstrate the laboratory's analytical competence. Accreditation bodies strongly encourage testing laboratories to participate in PT on a regular basis. Similarly, certification bodies also recommend participation in PT for the quality management system (e.g. EN ISO 9001 “Quality Management Systems – Requirements”, IATF 16949 “Requirements for the Quality Management System for Series Production and Automotive Parts”).