CUTTING FLUIDS — MICROBIAL ACTION

A cutting-fluid manufacturer has the responsibility of producing a product which performs the desired metal-working operation in the most efficient way possible, has no adverse effect upon human health, is as resistant as is possible to spoilage, and can be disposed of via some currently available method. The producer must also be able to provide technical information pertaining to usage and appropriate preservatives that may be employed in the product. The user has the responsibility to employ the product properly. This includes minimizing its contamination with different coolants, metals, tramp oils, dirt, food, and other materials; keeping the proper coolant dilution, employing satisfactory sanitation, minimizing human contact with the coolant, adding a preservative periodically to prevent rancidity, and not discarding it in such a way as to produce an environmental problem. Cutting-fluid users often purchase these increasingly expensive lubricants and use them under conditions which cannot possibly provide satisfactory coolant life or employee well being. Evidence for this practice is indicated in numerous NIOSH Health Hazard Evaluation Reports regarding inspections of machining operations in a number of plants. All of these reports note infractions of standards for proper usage as the cause of the problems noted; none cite the cutting-fluid manufacturer nor do any as yet recommend substitution of another cutting fluid for the one being used. In order to avoid problems in this area, greater attention must be given to choosing coolants that are least deleterious to human health, selecting machines which minimize worker contact and rancidity problems, minimizing oil mist and noise levels, ensuring better housekeeping practices, using proper preservatives, and keeping coolants in a sanitary condition. If this is not done, the industry will undoubtedly be subjected to increasing supervision and restrictions imposed by state and federal governments.