Removal efficiencies

Abstract

This chapter advances on the topic of descriptive statistics (Chapters 5 and 6), focusing now on removal efficiencies and the specificities associated with their calculation and interpretation. Different ways of presenting removal efficiencies (percentages versus log reduction values) are explained. Specific aspects associated with the determination of removal efficiencies are discussed, such as the influence of water losses, the handling of censored data, and the consideration of minimum and maximum possible values. We provide guidance regarding the interpretation of removal efficiencies, and we emphasize the joint interpretation of removal efficiencies together with effluent concentrations. Different ways of determining measures of central tendency for removal efficiencies are presented and discussed, and typical patterns of the associated frequency distributions are also described.