Abstract
Workers were exposed to excessive noise when working in the sample preparation room of ALCOA Kwinana Refinery. The noise was mainly from the four BICO disk mills located side by side in the centre of the room. High noise level from each mill affected its operator and operators of other mills. The airgun used for cleaning sample residues further increased the workers’ noise exposure level. The sample preparation practice also generates dust. Workers had to use earmuffs on top of other bulky safety equipment, which made the job quite awkward. A simple noise control solution involving noise absorption treatment, noise transmission blockage and vibration damping, was proposed and implemented for this noise problem. After the treatment, the noise exposure level was significantly reduced to the level below the exposure standard for ten-hour shift, making the use of hearing protection unnecessary.