After documents 3 and 11, this is the third test method in the series. It discusses how packing machines should be designed to comply with hygiene design criteria and thereby with the requirements specified in Annex 1 of the Machinery Directive.1 To determine whether those criteria are met requires validation of the design and measurement of essential parameters. Proven methods for testing the performance of the various functions of packing machines are described. These methods may also be used by the manufacturer to optimise or redesign a packing machine and by the food processor who may want to compare different packing machines. Upon delivery, a packing machine needs to be checked by a commissioning procedure to be agreed in advance between the food processor and the supplier. Commissioning may include physical as well as microbiological tests. Additional tests are specified for commissioning of machines for aseptic packing.