EXPOSURE ASSESSMENT TO RESPIRABLE CRYSTALLINE SILICA PARTICLES DURING AIRFIELD MAINTNENANCE CONCRETE OPERATIONS

摘要

Crystalline silica is found in naturally occurring and manmade materials. According to OSHA, approximately 2.2 million people are exposed to silica each year (OSHA, 2002). These individuals are at an increased risk of silicosis, an incurable disease that is often fatal. The objective of this project was to determine if airport maintenance workers are exposed to crystalline silica over the current permissible exposure limit. Two days of sampling was conducted and it was determined that there was some exposure to the Airfield Paint Crew exceeding the action level. The highest employee exposure was at 0.362 mg/m3 with a corresponding PEL measured to be 0.455 mg/m3. The severity ratio has a score of 0.797 (any score greater than 1 is an overexposure). As shown by the mortality rates in several studies, there is evidence to suggest workers in the construction industry are at an increased risk of exposure to crystalline silica (NIOSH, 2008). This paper finally concludes that further sampling should be conducted to confirm the sampling results. If the results yield the same exposure, then the workers should be put into a respiratory protection program and engineering controls should be implemented to reduce exposure.