This part of ISO 6887 specifies rules for the preparation of samples and decimal dilutions for the microbiological examination of food products other than those covered in other parts of ISO 6887. ISO 6887-1 defines the general rules for the preparation of the initial suspension and decimal dilutions for microbiological examination. This part of ISO 6887 only describes methods of preparation that are applicable to several microorganisms simultaneously. It excludes the preparations that only apply to the detection and/or enumeration of a single microorganism where the methods of preparation are described in the relevant International Standard concerning that microorganism.