■为了评估P&H高架起重机在制动器维护和维修活动中潜在的空气中石棉暴露,以及在随后处理机械师的衣服时。
■在制动测试过程中测量了个人(n=27)和面积(n=61)的空气传播纤维浓度,移除,手工打磨,压缩空气的使用,拆卸和重新连接含温石棉的制动衬片,并重新安装制动衬片。机械师的衣服被用来测量衣服处理过程中的潜在暴露。
■所有制动衬片中含有19.9%至52.4%温石棉。在任何散装或空气传播样品中均未检测到闪石纤维。平均全移空气中温石棉浓度为0.035f/cc(PCM当量石棉专用纤维,或PCME)。在制动维护期间收集的基于任务的平均个人空气样本,打磨,压缩空气的使用,制动衬片拆卸任务范围为0至0.48f/cc(PCME)。与5-15分钟的衣物处理相关的计算的30分钟时间加权平均值(TWA)空气中温石棉浓度为0-0.035f/ccPCME。
■结果表明,在所有起重机制动器维护和衣物处理任务期间测得的个人和区域TWA纤维浓度均低于当前OSHA8-hTWA石棉允许暴露极限0.1f/cc。Further,根据制造商的维护手册程序,在常规制动维护任务中没有测量空气中的石棉纤维。在非常规任务期间测得的所有短期空气中温石棉浓度均低于当前的1f/cc的OSHA石棉30分钟行程极限。这项研究增加了有关高架起重机维护期间温石棉暴露潜力的可用数据。
UNASSIGNED: To evaluate potential airborne asbestos exposures during brake maintenance and repair activities on a P&H overhead crane, and during subsequent handling of the mechanic\'s clothing.
UNASSIGNED: Personal (n = 27) and area (n = 61) airborne fiber concentrations were measured during brake tests, removal, hand sanding, compressed air use, removal and reattachment of chrysotile-containing brake linings, and reinstallation of the brake linings. The mechanic\'s clothing was used to measure potential exposure during clothes handling.
UNASSIGNED: All brake linings contained between 19.9% to 52.4%
chrysotile asbestos. No amphibole fibers were detected in any bulk or airborne samples. The average full-shift airborne
chrysotile concentration was 0.035 f/cc (PCM-equivalent asbestos-specific fibers, or PCME). Average task-based personal air samples collected during brake maintenance, sanding, compressed air use, and brake lining removal tasks ranged from 0 to 0.48 f/cc (PCME). The calculated 30-minute time-weighted average (TWA) airborne
chrysotile concentration associated with 5-15 minutes of clothes handling was 0-0.035 f/cc PCME.
UNASSIGNED: The results indicated that personal and area TWA fiber concentrations measured during all crane brake maintenance and clothes handling tasks were below the current OSHA 8-h TWA Permissible Exposure Limit for asbestos of 0.1 f/cc. Further, no airborne asbestos fibers were measured during routine brake maintenance tasks following the manufacturer\'s maintenance manual procedures. All short-term airborne
chrysotile concentrations measured during non-routine tasks were below the current 30-minute OSHA excursion limit for asbestos of 1 f/cc. This study adds to the available data regarding
chrysotile exposure potential during maintenance on overhead cranes.