Metal Finishing Guide Book


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Small Business Ombudsman provides literature and a toll-free hot-line to answer questions. Primary assistance for a business comes from the state SBAP office, and a small business can find out who to contact on a state level by calling the federal Small Business Ombudsman's hotline: 1-800/368-5888. The Halogenated Solvents Industry Alliance (HSIA), a trade association of producers of chlorinated solvents, provides legislative and regulatory news for the solvent industry, sponsors research on chlorinated solvents, and presents information from research to the EPA and other solvent regulators. Users of chlorinated solvents can obtain information from this organization, as well as literature on the use of the solvents and how to comply with regulations, by calling HSIA at 202/775-0232. Help is also available from the producers of chlorinated solvents. Producers and distributors are required by law to provide a MSDS, containing complete information on safety and handling, to all customers. In addition many producers also supply other forms of assistance. PROCEDURES FOR REDUCING EMISSIONS Emission standards for chlorinated solvent degreasing operations are now governed by EPA's NESHAP for new and existing halogenated solvent cleaning operations. These standards cover both vapor degreasing and cold cleaning with TCE, PCE, and MEC, as well as with chloroform. The goal of the NESHAP regulation is an overall reduction in solvent emissions of 50 to 70% of current nationwide emissions. The NESHAP provides a number of control procedures for reducing solvent emissions from equipment. Operators of batch vapor degreasers and in-line cleaning machines may choose from a series of combinations of two or three of the procedures, which include: • Freeboard ratio of 1.0: The height of the freeboard above vapor level must be equal to the width (shorter dimension) of the degreaser. • Freeboard refrigeration device: This is a refrigerated system that supplements or replaces the traditional water cooling system and creates a cold air blanket above the vapor zone. • Reduced room draft: Wind speed above the freeboard must not exceed 50feet per minute (15.2 m/min). • Working-mode cover: This is defined as any cover or machine design that shields the cleaning machine from outside air disturbances during the parts cleaning cycle. • Dwell: This refers to the time in which cleaned parts remain in the freeboard area above the vapor zone after cleaning. The EPA defines proper dwell time as 35% of the time required for the parts to cease dripping in the vapor zone. • Superheated vapor (vapor temperature maintained 10oF above the boiling temperature of the solvent): This promotes more thorough drying of the work before it is removed from the degreaser. • Carbon adsorption equipment in the ventilation system connected with the degreaser. In addition vapor degreasing operators must employ an automated hoist or conveyor that carries parts at a controlled speed of 11 fpm or less through the 113

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