General information about PT rounds

The Drinking water program comprises two rounds per year – March & September.

The Food program comprises three rounds per year - January, April & October.

Delivery of samples

Each round comprises 2-4 freeze-dried sub-samples from homogenous mixtures of microorganisms.

The material is sent 1-2 weeks before each round to all laboratories that are registered for the particular scheme.


The registration or cancellation to participate in a particular round has to be done using the tab Participation on this website, before the Last date for registration specified for that round.

Reporting of results

Recording of results has to be done on this website before the specified Last date for reporting. Reported results may be modified until that date.

The laboratories need only report results from the analyses of their interest.

Mail, e-mail or fax may be used for reporting of results, after contact with the organiser and if it is impossible to use the website.

Reporting of method information

Method information can only be reported by using the website.

The method information stored in the database is not round specific. It is shown on this website and used in the results evaluations as originally recorded, until the laboratory makes any changes.