Comparison of mist generation rates for an experimental metal removal fluid with a baseline fluid during milling and turning operations at TechSolve, Inc., Cincinnati, Ohio.
Khan A; Gressel M; Shulman S
Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, EPHB 218-15a, 2005 Nov; :1-88
Metal removal fluids have been used since the mid-1800s, and their use and formulation have changed over the years to accommodate performance, health and safety concerns. Recen!!y, adverse health effects were reported in industries using metal removal fluids, drawing /"" renewed attention to methods for controlling occupational exposures to metal removal fluids. In addition to the potential occupational hazards associated with metal removal fluids, disposal of the used metal removal fluids is also a concern to many machining operations. Recently, the identification of many metal removal fluids as hazardous wastes has been a force of change in industry. This classification has lead to the need for more advanced waste treatment and increased disposal costs for common metal removal fluids. This situation has also led to the development of metal removal fluids that are "Environmentally Friendly" which are easily disposed of and have a reduced environmental impact. To address the health, safety and environmental concerns, the U.S. Environmental Protection Agency (EP A) has been funding research at the University of Cincinnati to develop a metal removal fluid that is environmentally safer and has a good performance across a wide range of machining processes. Recently, research at the University of Cincinnati produced a synthetic metal removal fluid that is toxicologically and environmentally benign. The primary objective of this study was to compare the generation rate of respirable aerosols between the EP A fluid and a baseline fluid. Two machining processes were studied: milling and turning. The mist generation rate for milling was evaluated at two speeds while the mist generation rate for turning was evaluated at a single speed. The results of this study showed that, for the machining conditions studied, the EP A fluid produced significantly higher mist generation rates than the baseline fluid at lower and higher milling speeds. However, the differences in mist generation rates between the two fluids appear to diminish as machining speed increases. During turning, no statistically significant differences in mist generation rates between the EP A fluid and the baseline fluid were observed. Comparisons of the milling and turning operations by fluid type indicate that the mist generation rates for the EP A fluid during milling were significantly higher than those of this same fluid during turning, whereas baseline fluid generation rates during milling were significantly lower than those during turning. Overall, it can be concluded that the mist formation associated with the milling may be more dependent on the fluid characteristics of the metal removal fluids, while the turning operation may not be as dependent on the characteristics of the fluids, but more dependent on the operational variables. Since the workers' exposure to EPA fluid during milling was above the NIOSH REL, any company planning to use this fluid in their milling operation should provide a mist collector. The mist generations associated with turning for the EP A and baseline fluids were very .near the NIOSH REL. Therefore, companies with machining operations should consider mist collection devices on its turning equipment.
Cutting-oils; Metal-workers; Metalworking; Metalworking-fluids; Metalworking-industry; Synthetic-materials; Control-technology; Machine-operation; Aerosols; Region-5; Exposure-assessment; Environmental-factors; Aerosol-generators; Exposure-limits
National Institute for Occupational Safety and Health, Division of Applied Research and Technology, Engineering and Physical Hazards Branch, Mail Stop R-5, 4676 Columbia Parkway, Cincinnati, OH 45226-1998
Field Studies; Control Technology
NTIS Accession No.
National Institute for Occupational Safety and Health