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To guarantee the quality of the research, Vertify has developed a quality assurance system in addition to GLP, GEP, and TNG. The ISO-9002 certification was issued for this purpose in 1999, later followed by ISO-9001.



GEP (Good Experimental Practice) is a quality system that aims to ensure the proper performance of efficacy trials for crop protection products. Vertify has had a GEP certification since 1997. These trials, carried out under GEP, investigate the efficacy and/or selectivity of a crop protection product and are mandatory for the authorization of a crop protection product.

The purpose of the GEP certification is to ensure that trials are of high quality and performed in a balanced manner. The trials must be carried out according to European (EPPO) guidelines.

In 2015, the Netherlands Food and Consumer Product Safety Authority (NVWA) conducted a comprehensive audit of the procedures, equipment, staff files, and archives and renewed our GEP certification. In addition to this major audit, the NVWA performs some six to eight annual audits during the performance of a trial. This involves checking whether the installation of the trial, as well as spraying and assessment, are compliant with the procedures. Vertify’s GEP certification was renewed for another six years in 2015.

Besides the Dutch GEP certification, Vertify obtained the Belgian GEP certification a few years ago and is therefore accredited to perform efficacy trials in Belgium as well. The Belgian GEP accreditation was issued on the basis of mutual recognition from the Netherlands.

GLP and residu studies

GLP (Good Laboratory Practice) is a quality system for laboratories and research companies. Residue studies performed under GLP can be used for authorization for crop protection products. GLP trials are set up and carried out according to Organisation for Economic Co-operation and Development (OECD) guidelines and Vertify’s own procedures. By following GLP guidelines, Vertify ensures that the results of the residue studies are a true representation of reality.

Application of non-authorized crop protection products (TNG)

Vertify gained its ‘TNG-erkenning’ (Accreditation for the application of non-authorized crop protection products) in 2011. Until 1 April 2011, it was only possible to perform field studies with unauthorized plant protection products on the basis of an exemption for trial purposes (‘proefontheffing’) from the Board for the Authorisation of Plant Protection Products and Biocides (Ctgb). After the TNG accreditation scheme entered into force on 1 April 2011, TNG-accredited companies no longer require trial exemption for field studies with unauthorized crop protection products.

TNG accreditation ensures the safe conduct of research for humans, animals, and the environment. The requirements are similar to those of an exemption for trial purposes. To obtain TNG accreditation, regulations and rules must be an integral part of the quality system.

In 2015, following a thorough audit of the procedures, equipment, staff files, and archives for factors applicable to the TNG accreditation, the NVWA renewed our accreditation for six years. In addition to this major audit, the NVWA performs annual audits during the performance of a trial and examines whether our procedures comply with the TNG accreditation.