ABSTRACT
History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 585 Case Situation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 587 Communication Gaps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 588 Conclusion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 589
HISTORY
Communication is the one of the biggest challenges faced by all parties concerned with critical cleaning applications. In the past, when the use of chlorofluorocarbons (CFCs) and 1,1,1-trichloroethane (TCA) were ubiquitous as cleaning solvents and their usage was encouraged by the air agencies, the regulatory issues were much simpler to communicate. These solvents were considered unreactive organic gases, were considered not responsible in the formation of photochemical smog (ozone) in the air basins, and, therefore, were exempt from most of the regulations. Permits for degreasing equipment using these solvents were issued by the air agencies and there were no restrictions on usage, especially for CFC-113. TCA typically contained a cosolvent, 1-4-dioxane, approximately 5% by weight, and this cosolvent was considered photochemically reactive. The reactive hydrocarbon emissions calculated from the degreaser using TCA were based on 1-4-dioxane weight fraction and TCA usage. The physical chemistries of these solvents-low boiling point, low toxicity, nonflammable, fast drying time-resulted in large consumption of the solvents in the cleaning industry. The air permits for degreaser using CFCs and TCA were fairly standard and issued without much difficulty.
