某己内酰胺合成企业噪声暴露致听力损失的风险评估

Risk assessment on hearing loss induced by occupational noise exposure in a caprolactamate synthesis enterprise

目的对南京市某己内酰胺合成企业生产性噪声进行暴露风险评估和听力损失风险分级,提出噪声职业病危害风险管理措施。方法测量作业人员个体噪声接触水平,依据GBZ/T 229.4-2012《工作场所职业病危害作业分级第4部分:噪声》评估噪声作业等级;运用ISO 1999:2013方法,计算各岗位听阈级变化、听力损失风险,并依据AQ/T4276-2016《噪声职业病危害风险管理指南》进行风险分级。结果25人噪声检测结果超过80 dB(A),为噪声作业岗位。硫铵装置、磷酸羟胺法(hyam-phoshate oximation,HPO)老线、HPO新线、己内酰胺(caprolactam,CPL)老线外操工岗位噪声危害作业分级为Ⅰ级,轻度危害;各噪声岗位员工工作到50、60岁时发生高频听力损失风险概率均低于6%,属于可接受的风险。3种护听器正常使用下能够满足噪声的防护要求。结论对生产性噪声职业接触情况及时进行调查与风险评估,根据风险评估结果正确使用护听器,能够有效预防听力损失。

Objective In order to propose appropriate measures against noise at workplaces,the classification of occupational noise exposure level and risk of hearing loss in a caprolactamate synthesis enterprise was done.Methods The noise level was measured by personal noise-meter.The occupational health risks of noise was evaluated according to the GBZ/T 229.4-2012(the Classification of occupational hazards in workplace,part 4:noise),the change of hearing threshold level and the risk of hearing loss for each worker was calculated according to ISO 1999:2013,and the risk classification was made based on the AQ/T 4276-2016.Results The noise level at some worksites was higher than 80 dB(A),and the classification of noise level was ranked as lightly hazard(Ⅰ).The risk of high frequency hearing loss at current exposure level would be below 6%for the exposed workers till they are 50 or 60 years old,which could be acceptable.Three kinds of hearing protectors used at present could protect the workers’hearing.Conclusions The correct use of hearing protectors,which is selected based on the results of risk assessment of hearing loss caused by occupational noise exposure,can protect the hearing loss effectively.