One commonly used indicator for rating the cleaning strength of a non-aqueous solution is the Kauri-Butanol (KB) value. It can range anywhere from very mild (10) to very strong (+1000). The higher the value, the better the relative cleaning power.

Nevertheless, a high KB value can also cause materials compatibility issues if the strength of the cleaning is proving too aggressive for certain materials. Please note that KB value is not applicable for water.


When cleaning geometrically complex components, both surface tension and viscosity of the cleaning agent should be considered.

Surface tension is defined as the attraction of molecules on a liquid’s surface. The higher the surface tension, the higher the tendency of liquid surfaces to shrink into the minimum surface areas possible.

Given that solvents have lower surface tension than water, they have greater ability to wet a surface (as well as evaporate out of tiny places) and can thus more effectively permeate tight clearance areas to remove soils.


Viscosity measures a liquid’s resistance to flow. The lower the viscosity, the better a liquid can flow around objects and get into (and out of) tight spaces more easily.