THE EFFECTIVENESS OF LOCAL EXHAUST VENTILATED (SHROUDED) HAND POWER TOOLS USED FOR GRINDING SANDING COMPOSITE-MATERIALS/

The effectiveness of one particular shrouded tool type in capturing co mposite dust generated during dry machining operations was tested. The effectiveness of the shrouded tool was measured by comparing exposure s during identical operations done by the same worker. The operation w as conducted by dividing the time into two equal portions, one using a n unshrouded tool and the other with same tool shrouded. The operation s included sanding and grinding operations of fibrous glass/epoxy comp osite materials. Unshrouded short-term exposures ranged from 2.17 mg/m (3) to 50.81 mg/m(3). There was a significant reduction in exposure us ing the shroud (paired t-test, p=0.005). The effect of a shroud on res pirable dust exposures was inconclusive, because of the limited amount of respirable dust collected in these short-term samples.