Verifying the compliance of digestate with hygienic and sanitary standards involves recording a total absence of the salmonella microbiological parameter in 5 samples out of 5. What is the correct approach to take in this sampling process? How can any critical issues be handled? What checks and methods can be used to restrict as much as possible any re-contamination or cross-contamination of the sampled flow? Lorella Rossi explains this self-checking stage in detail. Full information can also be found in the CIB manual “Guidelines for the agronomic use of digestate”.