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For years those industries requiring precision cleaning in their production operations had access to chemical solvents which, because of their extraordinary properties and when used with the appropriate process and equipment, would suffice to precision clean virtually everything requiring precision cleaning. Principle among these were 1,1,2-trichloro 1,2,2-trifluoroethane (CFC-113) and methyl chloroform (MCF). When the Montreal Protocol process identified these chemicals as ozone depleting chemicals (ODCs) and targeted them for complete phaseout, the industries requiring precision cleaning were challenged to develop and implement alternatives for CFC-113 and MCF. Efforts began immediately and worldwide with a great deal of success. Through those efforts there are now an abundance of alternatives for virtually every precision cleaning requirement. This sounds very impressive, and it truly is. Initially it would appear that there should no longer be any difficulties replacing CFC-113 and MCF within the industries using those chemicals for precision cleaning. However, upon examination this is definitely not the case. While it is true there are abundant alternatives, none of them are universal. For example, there is no substitute chemical that is a perfect replacement for either CFC-113 or MCF in all their applications. In addition, there are a variety of parameters associated with the alternatives that vary considerably among those alternatives. These include such things as environmental impact, cost, worker safety, flammability, storage lifetime, different levels of reactivity with different materials, and so on. To further compound the problem, these parameters vary in importance depending upon such things as the geographic area involved, type and nature of process requirements, and political concerns.

The Aerospace Guidance and Metrology Center located at Newark Air Force Base in the state of Ohio, U.S.A., repairs inertial navigation and guidance equipment for the United States Air Force. The Center repairs thousands of the delicate, sophisticated electromechanical devices each year. The critical tolerances of many of the moving parts and other considerations mandate extensive "precision" cleaning as well as general cleaning during the repair process. The principal solvents used for this cleaning are 1,1 ,2-Trichloro 1, 2, 2-trifluoroethane and 1,1 ,1-Trichloroethane. The Center has begun modifying its many cleaning processes to use known alternatives for these solvents. The Center has already converted several processes to deionized water and biodegradable detergents and has committed extensive internal resources to define and implement changes throughout its remaining processes. While this effort has not been easy, it has made visible some special considerations which will ease and expedite the transition in the future.

The Aerospace Guidance and Metrology Center located at Newark Air Force Base in the state of Ohio, U.S.A., repairs inertial navigation and guidance equipment for the United States Air Force. The Center repairs thousands of the delicate, sophisticated electromechanical devices each year. The critical tolerances of many of the moving parts and other considerations mandate extensive "precision" cleaning as well as general cleaning during the repair process. Among the parts requiring cleaning are precision instrument bearings and assemblies containing beryllium. The principal solvents used for this cleaning have been 1,1,2-Trichioro 1,2,2-trifluoroethane (CFC-113) and 1,1 ,1-Trichloroethane (MCF). The Center has begun modifying its many cleaning processes to use known alternatives for these solvents. Principal among these alternatives are aqueous processes using biodegradable detergents and deionized water. All of the Center's precision instrument bearing cleaning is now done with an aqueous process. Considerable testing and evaluation are nearing completion which indicate that aqueous processes will be used to precision clean beryllium parts with many improvements over the solvent based methods.

The purpose of the study was to establish a baseline for CFC-113 emissions and other losses that result from maintenance operations at AGMC. A total of 314,000 lb of CFC-113 was purchased in FY-1991. A great deal of it is emitted to the atmosphere.

The proceedings describe the first meeting of the Life Cycle Cost Task Group of the Joint Services Data Exchange for Inertial Systems. The report contains copies of educational presentations on various subjects connected with Life Cycle Costing and with Maintenance Warranties. (Author), See also report dated 25 Apr 74, AD-785 390.