Efficiency of a tool-mounted local exhaust ventilation system for controlling dust exposure during metal grinding operations.

In general, control of metal dust from hand-held disk grinders is difficult because such respirable dust tends to disperse in every direction around the grinding wheel and cannot be captured effectively by a conventional exhaust hood. The author described the application of a custom-made tool-mounted local exhaust ventilation (LEV) system attached to a hand-held disk grinder, and by laboratory experiments assessed its effectiveness at dust control. The effectiveness of the LEV for dust control was assessed by determining the respirable dust concentration around the grinding wheel during metal surface grinding with and without the use of the LEV. It was shown that the average respirable grinding dust concentration decreased from 7.73 mg/m(3) with the LEV off to 4.87 mg/m(3) with the LEV on, a mean dust generation reduction of about 37%.