摘要目的:了解机械制造类企业的职业噪声危害情况，使用适合性检验方法评价劳动者佩戴护听器后的个体降噪效果及影响因素。方法:于2021年11月至2022年1月，选取深圳市宝安区5家机械制造类企业进行职业卫生调查，了解劳动者噪声接触水平。使用3M TM E-A-Rfit TM护听器适合性检验系统测试485名典型噪声作业岗位的劳动者日常佩戴护听器的基线个人声衰减值水平（PAR），对PAR值不能满足工作降噪需求的劳动者进行佩戴指导并重复测试，收集干预前后劳动者的PAR结果并分析。 结果:接受适合性检验的噪声作业劳动者主要分布在24个工种，岗位噪声接触水平为80.2~95.0 dB（A），岗位噪声超标率为52.5%（138/263）。485名劳动者的基线PAR中位数[ M（ Q1， Q3）]为6.0（0.0，14.0）dB。男性、工龄>15年、使用护听器年限>15年、认为护听器佩戴舒适、大专及以上者文化程度以及接触噪声水平90 dB（A）劳动者的基线PAR较高，差异有统计学意义（ P<0.05）。共有275名工人（56.7%）未通过基线PAR测试，不同噪声分组的工人需干预率差异无统计学意义（ P>0.05）。经干预后未通过基线受试者的PAR从0.0（0.0，3.0）dB提升至15.0（12.0，18.2）dB。 结论:机械制造类企业的工作场所噪声危害严重，接噪劳动者佩戴护听器基线PAR与护听器的标称值存在较大差异。干预措施可有效提高劳动者佩戴护听器防护效果。

abstractsObjective:To investigate the occupational noise hazards in five machinery manufacturing enterprises, and to evaluate the individual noise reduction values and influencing factors of workers wearing hearing protection device (HPD) by individual fit testing.Methods:From November 2021 to January 2022, 5 machinery manufacturing enterprises in Bao'an District of Shenzhen were selected to conduct an occupational health survey to understand the noise exposure level of workers. The 3MTM E-A-RfitTM fitness test system was used to test the baseline individual sound attenuation value level (PAR) of the daily wear of the ear protecters for 485 workers in typical noise working positions. Workers whose PAR values could not meet the requirements of noise reduction at work were instructed to wear and repeated tests were conducted. PAR results of the workers before and after the intervention were collected and analyzed.Results:The noise workers who received the suitability test were mainly distributed in 24 types of work, the job noise exposure level was 80.2 dB (A) ~ 95.0 dB (A), and the job noise excess rate was 52.5% (138/263). The median baseline PAR [ M ( Q1, Q3) ] for 485 workers was 6.0 (0.0, 14.0) dB. The baseline PAR of male workers, those with more than 15 years of working experience, those with more than 15 years of using ear guards, those who considered ear guards comfortable to wear, those with college degree or above, and those exposed to noise level 90 dB (A) were higher, and the difference was statistically significant ( P<0.05). A total of 275 workers (56.7%) did not pass the baseline PAR test, and there was no statistically significant difference in the intervention rate of workers in different noise groups ( P>0.05). PAR in subjects who did not pass baseline after intervention increased from 0.0 (0.0, 3.0) dB to 15.0 (12.0, 18.2) dB. Conclusion:The workplace noise hazard of machinery manufacturing enterprises is serious, and there is a great difference between the baseline PAR and the nominal value of the hearing guard worn by the noise exposed workers. The intervention measures can effectively improve the protective effect of wearing ear protectors.