Coal ; Noise, Occupational ; prevention & control ; Steel

Objective: To explore the sound insulation, sound absorption and other noise reduction transformation methods in a noise workshop handover control room. Methods: In December 2021, through the occupational health investigation and on-site testing of the handover control room of a noise workshop, the causes of excessive noise were analyzed, and the transformation design scheme to reduce noise was proposed and the effect was analyzed. Results: Before the transformation, the peak frequency band noise intensity of the noise workshop handover control room was 112.8 dB (A), and the peak frequency was 1000 Hz. After noise reduction, the theoretical calculated control value was 61.0 dB (A), and the measured noise intensity was 59.8 dB (A) . Conclusion: The noise intensity of the handover control room is reduced after noise reduction, which is in line with the contact limit requirements of the control room in GBZ 1-2010 "Hygienic Standards for the Design of Industrial Enterprises", and has reference significance for noise control engineering.
Noise/prevention & control* ; Occupational Health ; Industry ; Reference Standards ; Hygiene ; Noise, Occupational/prevention & control*

OBJECTIVETo investigate the industrial noise over-limit status of the worksites in Guangzhou factories, so as to promote the prevention and control of occupational noise hazards.

METHODS211 factories in Guangzhou were monitored and investigated. The analysis and assessment were developed for the properties and size of the factories, the districts of the factories being located, the industries of the factories being classified and the date of monitoring.

RESULTSIn this understudied factories, most of them were national-owned and joint-ventures, medium size, located in urban, and mainly involved in the industries of manufacturing of motor vehicle, shipping, electron and electric equipment, and the industries of petroleum and chemicals. The prevalence of noise over-limit was higher in joint-ventures (36.0%) and private-run enterprises (31.2%). The over-limit status mainly presented in industries of textile, food and beverage processing, and leather producing, with getting prevalence of over-limit 46.7%, 43.1% and 41.3% respectively. Subsequence were industries of manufacturing of electron and electric equipment, motor vehicle and shipping, and industries of printing and goods producing for culture and sports, with the prevalence for all > 35%. Factories monitored during spring and summer also had higher prevalence of noise over-limit. The similar results were got after adjustment for each other using multivariable regression. The most common over-limit sites mainly focused on the operation of cutting and sawing, milling and planing, pressing, riveting, drilling, jointing, assembling and quality inspecting in industries of mechanism processing and manufacturing, on quality inspecting and packing in industries of pharmacy and food and beverage manufacture, on spinning and scutching in textile industry, and on cleaning and maintaining as assistant jobs, and patrolling and inspecting air-press machine, ventilation machine, dynamotor and pump.

CONCLUSIONNoise in Guangzhou factories widely exists with different industries and districts. To strengthen noise occupational hazards prevention and control for the high risk districts, industries and worksites should be the key job in the future.

Humans ; Noise, Occupational ; adverse effects ; prevention & control ; Ships

Noise, Occupational ; prevention & control ; Occupational Health Services ; standards ; Threshold Limit Values

Objective: To get insight into the current practice of noise reduction effect of workers as they wore hearing protectors in different domestic enterprises and the possible affected factors. Methods: From October 2020 to April 2021, using a random sampling method, 1197 workers exposed to noise in petrochemical factories, textile factories, and parts manufacturing factories were selected as the study subjects. The noise reduction effect of hearing protectors worn by workers in daily use was tested using a hearing protector suitability testing system. The personal sound attenuation level (PAR) was compared among workers in three enterprises, Targeted intervention and repetitive testing were conducted for workers who did not meet the noise reduction effect required by the enterprise, and the changes in PAR of workers before and after the intervention were compared. The comparison of baseline PARs between two or more groups was performed using the Mann Whitney test, the comparison of baseline PARs with post intervention PARs was performed using the Wilcoxon signed rank sum test, and the comparison of qualitative data between two or more groups was performed using the Chi square test. Results: The median baseline PAR for all workers was 15 dB. Men, age<30 years old, education level at or above college level, working experience of 5 to 15 years, and those who used hearing protectors for 5 to 15 years had higher PARs, with statistically significant differences (P<0.05). The median difference in baseline PAR among workers from three enterprises was statistically significant (H=175.06, P<0.01). The median PAR of subjects who did not pass the baseline increased from 3 dB to 21 dB after intervention (Z=-27.92, P<0.01) . Conclusion: Some workers wearing hearing protectors do not meet the required PAR, and low PARs may be related to incorrect wearing methods and incorrect selection of hearing protectors. As a tool for testing, training, and assisting in selection, the hearing protector suitability testing system is of great significance for worker hearing protection.
Male ; Humans ; Adult ; Hearing Loss, Noise-Induced/prevention & control* ; Ear Protective Devices ; Noise, Occupational/prevention & control* ; Hearing ; Audiometry

China ; Hearing Loss, Noise-Induced ; prevention & control ; Hearing Tests ; standards ; Humans ; Noise, Occupational ; adverse effects ; legislation & jurisprudence ; prevention & control ; Occupational Diseases ; prevention & control

Adult ; China ; Hearing Loss, Noise-Induced ; etiology ; prevention & control ; Humans ; Middle Aged ; Noise, Occupational ; adverse effects ; prevention & control ; Occupational Exposure ; adverse effects ; prevention & control

PURPOSE: This study was done to identify the distribution and related factors for stage of change for wearing hearing protection devices (HPDs) by workers in environments with high noise. Predictors of Use of Hearing Protection Model and Trans-theoretical Model were tested. METHODS: The participants were 755 workers from 20 noisy work places in Busan and Gyeongnam. Data were collected from January to April 2008 using self-administered questionnaires, and analyzed using multiple logistic regression. RESULTS: There were significant differences in social mode (OR=1.35, 95% CI: 1.06-1.73) between precontemplation/contemplation and preparation stage, in males (OR=2.36, 95% CI: 1.24-4.51), workers with high school education or less (OR=1.39, 95% CI: 1.28-2.78), shift workers (OR=1.50, 95% CI: 1.02-2.21), workers who previously worked in noisy places (OR=1.39, 95% CI: 1.20-2.34), and workers who had previous hearing examinations (OR=1.89, 95% CI: 1.25-2.85), in the social model (OR=1.59, 95% CI: 1.42-1.78), and self-efficacy (OR=1.05, 95% CI: 1.02-1.08) between workers in preparation and action stages, in length of time working in noisy work places (OR=2.26, 95% CI: 1.17-4.39), social model (OR=1.66, 95% CI: 1.33-2.08), and perceived benefit (OR=0.95, 95% CI: 0.93-0.97) between action and maintenance stage. CONCLUSION: Social model was a common factor showing differences between two adjacent stages for wearing HPDs. The results provide data for developing programs to encourage workers to wear HPDs and application of these programs in work settings.
Adult ; Ear Protective Devices/*utilization ; Female ; Hearing Loss, Noise-Induced/*prevention & control ; Humans ; Male ; Middle Aged ; Noise, Occupational ; Occupational Exposure/prevention & control ; Questionnaires ; Self Efficacy ; Workplace

OBJECTIVETo study the main factors affecting sound-insulation effects of control rooms in workshops with noise, so as to improve the protection.

METHODSThe sound-insulation effects of 467 control rooms were determined, and different building materials, structures of door and window, airtight states etc. were analyzed.

RESULTSThe affecting factors contributed to the sound-insulation effects (Eta(2)) were in the order: airtight states (0.168), building materials (0.080), structures of window and door (0.030, 0.029), sound pressure levels and frequency spectrum's characteristics (0.008, 0.006). Under airtight state, the sound-insulation effects of different building materials of the rooms were as follows: double bricks [(19.6 +/- 3.5) dB(A)]; single brick [(15.4 +/- 3.4) dB(A)]; plank [(13.1 +/- 1.6) dB(A)] or aluminum alloy plate with glass [(13.4 +/- 2.5) dB(A)] (P < 0.01). Of 4 group rooms, with the same structure of doors but double or single bricks of windows. 3 groups with dormant window had higher sound-insulation effects [(15.9 +/- 2.8), (18.7 +/- 3.6), (19.3 +/- 2.5) dB(A)] than those with casement window [(14.1 +/- 2.4), (14.9 +/- 2.3), (16.5 +/- 2.4) dB(A)] (P < 0.01 or P < 0.05); 2 groups with dehydrated window [(18.7 +/- 3.3), (22.6 +/- 3.8) dB(A)] higher than those with dormant window [(15.9 +/- 2.8), (19.9 +/- 3.0) dB(A)] (P < 0.05). Of 6 group rooms, with the same structure of windows but double or single bricks of doors, only in 1 group with double-layer door had higher sound-insulation effect [(18.7 +/- 3.6) dB(A)] than that with single-layer door [(15.9 +/- 2.8) dB(A)] (P < 0.01).

CONCLUSIONThe control room should be designed rationally, kept airtight, according to the sound pressure levels and the condition of the workshop.