This Technical Specification gives guidance for the estimation and expression of measurement uncertainty (MU) associated with quantitative results in food microbiology. It is applicable to the quantitative analysis — of products intended for human consumption and the feeding of animals, and — of environmental samples in the area of food production and food handling, typically carried out by enumeration of microorganisms using a colony-count technique, but applicable also to quantitative analysis by alternative instrumental methods. This Technical Specification is not applicable to — enumeration using a most probable number technique, or — the analysis of low levels of microorganisms. In this Technical Specification, MU associated with “low” numbers of organisms 1), as described by ISO 7218, is not estimated due to a lack of a simple agreed approach to cover this case. The approach of this Technical Specification is a global approach, based on the standard deviation of reproducibility of the final result of the measurement.