|MadSci Network: Environment/Ecology|
There are standards for different degrees of cleanliness that depend on why the item is being cleaned. The cleaning methods would also depend on whether the material has a protective coating and whether or not the coating is to be preserved.
One of the best internet sites for searching for standards like this is the American Society for Testing and Materials, ASTM. Most good libraries have a full set of the ASTM standards. A quick search on their web site at http://www.astm.org/ revealed the following standards that may be applicable to your problem.
Standard Practice for B322-85 Cleaning Metals Prior to Electroplating
Standard Practice for D4174-89 Cleaning, Flushing, and Purification of Petroleum Fluid Hydraulic Systems
Standard Practice for A380-96 Cleaning, Descaling, and Passivation of Stainless Steel Parts, Equipment, and Systems
Again, you would have to examine these standards for applicability to your problem, but they should serve as a good starting point.
Try the links in the MadSci Library for more information on Environment/Ecology.