GEP - Good Experimental Practice

Good Experimental Practice (GEP) shall ensure that trials testing for efficacy, phytotoxicity, side effects, and the risks for resistance development in Denmark are conducted according to the uniform principles, which ensure high quality and mutual recognition of trial results among the EU member states.

The set of rules

Plant protection products must be authorised according to the plant protection regulation (link to the Regulation (EC) 1107/2009) before they may be marketed and used. This authorisation process involves a thorough assessment of the properties of the plant protection products. To ensure a high and uniform standard of the laboratories and testing facilities, which conduct the trials on which the plant protection products are assessed, the trials are to be conducted according to the directive on good laboratory practice (GLP) (Link to the EU directive).

The conditions for field trials on efficacy of plant protection products are very different to the trials that can be conducted in the laboratory. Because of this, the set of rules for good laboratory practice is adjusted to the conditions field trials are subject to (See EU regulation on data requirements for plant protection products).

This set of rules are called good experimental practice (GEP). In Denmark, the rules are implemented in a statutory order of pesticides and are specified in the GEP Manual (Link to the GEP Manual)

Recognition of GEP trial facilities

Facilities and organisations that seek to conduct officially recognised efficacy trials with plant protection products must be recognised by the Danish GEP Recognition Unit. This is done by submitting an application form to the unit (Download the application form here).
As the relevant crops and cropping systems are very divers, the conditions for the expertise and equipment of the trial facilities differ among crops. However, a grouping of the cropping systems has been made (Link to cropping groups).

Conduction of GEP trials

Companies and organisations that wish to have GEP trials conducted may find the recognised testing facilities here (Link to list of GEP facilities).

GEP in the EU

The member states of the European Union cooperates in relation to recognition of GEP facilities (See the WEB portal of the EU-GEP corporation).