The precision components used in modern fluid powered machinery demand that strict consideration be given to cleanliness levels of the operating fluid. All fluid components exhibit an explicit sensitivity to the presence of contamination. When the contamination level of the fluid exceeds the tolerance level of the components, the performance, reliability and life of the system become affected. In order to establish a contamination control condition, the tolerance level of the components must be represented in a quantitative manner commensurate with the contamination level of the fluid.