Objective:To Exploring the protective effect of hearing protectors worn by noise workers in the petrochemical industry and the factors affecting the protective effect of hearing protectors.Methods:From June 2021 to July 2023, 929 petrochemical workers were selected as the research subjects through cluster sampling. The noise exposure of workers and the usage of two types of hearing protectors were surveyed through questionnaire surveys and on-site occupational hygiene surveys. The protective effect of hearing protectors were evaluated by testing the PAR of workers. If the noise exposure value of workers minus the PAR value was less than 85 dB (A) , it was considered passed. Otherwise, it was considered not passed. The passing rate of the protective effect test of hearing protectors was analyzed through chi square test and the influencing factors for the effectiveness of workers hearing protectors in test were explored through single factor analysis and logistic regression models.Results:Among the research subjects, 80.5% of workers (748/929) had noise exposure levels greater than 85 dB (A) . The passing rate (80.9%) of the earmuff is greater than that of the earplug (52.6%) , and the median of PAR of the earmuff is 22 (16, 25) , which is greater than that of the earplug 15 (3, 22) dB dB, with a statistically significant difference ( P<0.001) . Univariate analysis and logistic regression models showed that length of service, exposure level to noise, and wearing comfort were the influencing factors of earplug protection effect ( P<0.05) , while wearing comfort was the influencing factor of earmuff protection effect ( P<0.05) . Conclusion:This study indicates that the protective effect of hearing protectors on workers in the petrochemical enterprise is poor, and the protective effect of earmuffs is greater than that of earplugs. Working experience, noise exposure level, and wearing comfort are the influencing factors of earplug protection effect, while wearing comfort is the influencing factor of earplug protection effect.

In workplaces where formaldehyde, hydrochloric acid and water vapor coexist, dichloromethyl ether can be produced. Dichloromethyl ether has strong carcinogenicity. Its target organ is the lungs, and the common tissue type of lung cancer is small cell lung cancer. This paper analyzes the cause of a case of occupational tumor (lung cancer caused by dichloromethyl ether) in the electroplating industry. Through the use of on-site occupational health investigation method, engineering analysis method and detection and inspection method, the occupational disease diagnosis is diagnosed in combination with the patient's occupational contact history, clinical symptoms and workplace occupational disease hazard factors. According to GBZ 94-2017 "Diagnosis of Occupational Tumor", the patient in this case was clearly diagnosed with primary lung cancer and was diagnosed as an occupational tumor (lung cancer caused by dichloromethyl ether) .

Acute Gelsemium poisoning is a systemic disease primarily affecting the central nervous system and respiratory symptoms caused by the ingestion of a substantial amount of Gelsemium within a short period. It manifests as sudden onset and rapid progression, primarily caused by accidental ingestion due to misidentification, and posing significant health risks. The compilation of the Technical Plan for Emergency Health Response to Acute Gelsemium Poisoning describes in detail the specialized practice and technical requirements in the process of handling acute Gelsemium poisoning, including accident investigation and management, laboratory testing and identification, in-hospital treatment, and health monitoring. The guidelines clarify key procedures and requirements such as personal protection, investigation elements, etiology determination, medical rescue, and health education. The key to acute Gelsemium poisoning investigation lies in promptly identifying the toxin through exposure history, clinical manifestations, and sample testing. Because there is no specific antidote for Gelsemium poisoning, immediate removal from exposure, rapid elimination of the toxin, and respiratory monitoring are critical on-site rescue measures. Visual identification of food or herbal materials, followed by laboratory testing to determine Gelsemium alkaloids in samples is a rapid effective screening method. These guidelines offer a scientific, objective, and practical framework to support effective emergency responses to acute Gelsemium poisoning incidences.

Objective:To Exploring the protective effect of hearing protectors worn by noise workers in the petrochemical industry and the factors affecting the protective effect of hearing protectors.Methods:From June 2021 to July 2023, 929 petrochemical workers were selected as the research subjects through cluster sampling. The noise exposure of workers and the usage of two types of hearing protectors were surveyed through questionnaire surveys and on-site occupational hygiene surveys. The protective effect of hearing protectors were evaluated by testing the PAR of workers. If the noise exposure value of workers minus the PAR value was less than 85 dB (A) , it was considered passed. Otherwise, it was considered not passed. The passing rate of the protective effect test of hearing protectors was analyzed through chi square test and the influencing factors for the effectiveness of workers hearing protectors in test were explored through single factor analysis and logistic regression models.Results:Among the research subjects, 80.5% of workers (748/929) had noise exposure levels greater than 85 dB (A) . The passing rate (80.9%) of the earmuff is greater than that of the earplug (52.6%) , and the median of PAR of the earmuff is 22 (16, 25) , which is greater than that of the earplug 15 (3, 22) dB dB, with a statistically significant difference ( P<0.001) . Univariate analysis and logistic regression models showed that length of service, exposure level to noise, and wearing comfort were the influencing factors of earplug protection effect ( P<0.05) , while wearing comfort was the influencing factor of earmuff protection effect ( P<0.05) . Conclusion:This study indicates that the protective effect of hearing protectors on workers in the petrochemical enterprise is poor, and the protective effect of earmuffs is greater than that of earplugs. Working experience, noise exposure level, and wearing comfort are the influencing factors of earplug protection effect, while wearing comfort is the influencing factor of earplug protection effect.

In workplaces where formaldehyde, hydrochloric acid and water vapor coexist, dichloromethyl ether can be produced. Dichloromethyl ether has strong carcinogenicity. Its target organ is the lungs, and the common tissue type of lung cancer is small cell lung cancer. This paper analyzes the cause of a case of occupational tumor (lung cancer caused by dichloromethyl ether) in the electroplating industry. Through the use of on-site occupational health investigation method, engineering analysis method and detection and inspection method, the occupational disease diagnosis is diagnosed in combination with the patient's occupational contact history, clinical symptoms and workplace occupational disease hazard factors. According to GBZ 94-2017 "Diagnosis of Occupational Tumor", the patient in this case was clearly diagnosed with primary lung cancer and was diagnosed as an occupational tumor (lung cancer caused by dichloromethyl ether) .

Respiratory protective equipment (RPE) is an effective measure to protect the health of workers. The domestic and foreign facial classfication of fit testing of RPE is mainly categorized into Los Alamos National Laboratory (LANL) classification, National Institute for Occupational Safety and Health (NIOSH) classification, principal component analysis (PCA) classification, Chinese Han adult facial classification, and Chinese young male facial classification. The LANL classification has low applicability. The NIOSH classification included different ethnicity and region of the study subjects, which is more representative for the American population. The PCA facial classification is complex to use and has low matching with RPE sizes. The Chinese Han adult facial classification and Chinese young male facial classification included more facial data of Chinese Han population and young population. There are qualitative and quantitative fit testing. Qualitative methods include the isoamyl acetate method, saccharin solution aerosol method, aerosol bitter testing solution method, and irritant smoke method which are cost-effective and easy to use, but are highly subjective to the study subjects. Quantitative methods include the aerosol generated method, environmental aerosol condensation nucleus counting method, and the controlled negative pressure method, which accurately quantify the facial fit of RPE but require specific testing equipment and high costs. It is necessary to include occupational populations from multiple industries, combine facial fit testing and fit testing methods of RPE, and establish a follow-up database based on digital information platforms, to achieve dynamic monitoring of respiratory protection levels among different occupational populations in the future.

Background Most of the studies on grading and classification of occupational health compre-hensive risks for specific employers still remain in the establishment and description of methodology, and practical application studies are rarely reported. Objective To explore the application of an occupational disease hazards comprehensive risk assessment method issued by the National Disease Control and Prevention Bureau in conjunction with the National Health Commission and a self-developed occupational health grading and classification method in petroleum refining enterprises, and to provide practical experience for the implementation of differentiated law enforcement by relevant regulatory authorities. Methods Two occupational health grading and classification methods were practiced in three petroleum refining enterprises in Guangdong Province. The occupational hazards comprehensive risk assessment method was provided by the Notice on Carrying out Pilot Work of Occupational Health Classification Supervision and Law Enforcement of the National Disease Control and Prevention Bureau and the National Health Commission. The principle was to derive the occupational health risk level according to nature of occupational hazards, exposure level, and number of workers exposed to them in an employer, and then to classify them into Class A, Class B, and Class C by combining with local occupational health management status level. The occupational health grading and classification method was self-developed according to available domestic and foreign occupational health risk assessment methods. Its principle was to calculate the risk level of each workstation in an employer based on published carcinogenicity classification or LD₅₀/LC₅₀ of chemical toxicants, level of noise, exposure parameters such as exposure level and exposure frequency, estimate the comprehensive risk R_o of the target employer by the Romanian comprehensive risk calculation method, and then calculate a comprehensive risk R_o' weighted by the occupational health management index of the target employer and classify it into class A, class B, and class C. Finally, assessment results, scope of application, inquired indicators, advantages,disadvantages and professional competence requirements of the two grading and classification methods were compared. Results The occupational hazards that were evaluated in three enterprises in this study were benzene, toluene, xylene, gasoline, hydrogen sulfide, and noise. The exposure levels of benzene, toluene, xylene, and gasoline were all below 10% OEL (occupational exposure limit), and hydrogen sulfide and noise were disqualified. Occupational hazards such as benzene and hydrogen sulfide were serious occupational hazards in the three enterprises, and the number of workers exposed was 461, 912, and 224, respectively; the HRs (hazard ratings) of benzene, toluene, xylene, gasoline, hydrogen sulfide, and noise were level 5, 3, 2, 3, 5, and 3 respectively. The occupational health management status of the three enterprises was graded as B, A, and B, respectively by the occupational disease hazards comprehensive risk assessment method. The occupational health management index of the three enterprises was graded as B, A, and A, respectively by the occupational health grading and classification method. The comprehensive risk assessment results showed that two enterprises classified into as the highest class C and one into class B by the occupational disease hazards comprehensive risk assessment method, while all three enterprises were classified into class B by the occupational health grading and classification method. Conclusion The two grading and classification methods are not consistent in the evaluation results of petroleum refining enterprises, and there are differences in the evaluation scope, indicators to be collected, and professionalism. It is recommended that occupational health regulators should fully consider the advantages and disadvantages of the two methods and choose the appropriate assessment method according to the actual regulatory purpose.

Objective: To explore the relationship between occupational stress, psychological capital and depressive symptoms among electronic manufacturing female workers in the Pearl River Delta region. Methods: Using cluster sampling method, 845 female workers from 5 electronic manufacturing enterprises in the Pearl River Delta region were selected as research subjects from June to August 2017. The Effort Reward Imbalance questionnaire (ERI) , Psychological Capital questionnaire-24 (PCQ-24) and Patient Health questionnaire-9 (PHQ-9) were applied to measure the level of occupational stress, psychological capital and depressive symptoms in female workers. Results: Effort (r=0.197, P<0.01) and over commitment (r=-0.260, P<0.01) were positively correlated with the score of depressive symptoms, and the rewards was negatively correlated with depressive symptoms (r=-0.211, P<0.01) . The reward and over-commitment for depressive symptoms were accounted for 8.2%. Psychological capital was negatively correlated with depressive symptoms, and plays a partly mediating role in the relationship between occupational stress and depressive symptoms of female workers. The psychological capital for depressive symptoms was accounted for 8.7%. Conclusion Occupational stress can affects the depressive symptoms of electronic manufacturing female workers, or indirectly affect depressive symptoms through psychological capital, reduce occupational stress and improve psychological capital as a way to relieve the depressive symptoms of female workers.

Objective : To explore the spatial distribution of occupational diseases in Guangdong Province and to provide evidence for the policy development of occupational disease prevention and control. Methods : A database of occupational disease incidence from 2009 to 2016 in Guangdong Province was built. The distribution of occupational diseases in Guangdong Province was displayed based on the geographic information system（GIS）, then spatial autocorrelation analysis and trend-surface analysis were carried out to explore the clustering areas and spatial epidemic characteristics of occupational diseases in Guangdong Province. Results : The number of cases with occupational diseases was 5 231 and was increasing year by year from 2009 to 2016 in Guangdong Province. The high-incidence areas were located in Guangzhou,Shenzhen,Foshan and Dongguan. Through global spatial autocorrelation analysis,it was found that there were spatial clustering of occupational diseases in Guangdong Province in each year（P<0.05）,and the cumulative incidence was also clustered（Moran's I=0.492,P<0.05）. The number of cases in Guangzhou,Shenzhen,Foshan and Dongguan had local spatial autocorrelation,and the local Moran's I values were 10.329,8.614,3.725 and 9.811,respectively（P<0.05）. The results of trend surface analysis showed that the overall incidence of occupational disease had a slight increase from west to east,and the Pearl River Delta region was a high-incidence area. Conclusion The incidence of occupational diseases in Guangdong Province had an obvious spatial clustering,the Pearl River Delta region was a high-incidence area.

Objective: To apply the semi-quantitative risk assessment model in the Technical Guidelines for Occupational Health Risk Assessment of Chemical Hazardous Factors in the Workplace to assess the occupational health risk of electroplating enterprises and explore its applicable conditions and characteristics. Methods: Three electroplating enterprises were selected as the research objects. Occupational hygiene survey and hazard factor detection were conducted on the spot. Three semi-quantitative risk assessment methods were used to assess the risk, and the evaluation results were compared. Results: The consistency between the contact index method and the comprehensive index method was strong. The weighted Kappa value was 0.946 and the P value was less than 0.001, but the consistency between the contact ratio method, the contact index method and the comprehensive index method was poor. The weighted Kappa value was 0.345 and 0.391, and the P value was 0.009 and 0.004, respectively. When the contact concentration is less than 50% OELs, the evaluation results of the contact ratio method are lower than those of the exponential method and the comprehensive exponential method. The consistency of the three methods was the highest when the contact concentration (>50%) and (OELs, the results of the contact ratio method are higher than those of the index method and the comprehensive index method. Conclusion Contact ratio method is suitable for occupational health risk assessment under the condition of incomplete occupational health information and for enterprise managers to identify key control points of health risk through self-assessment; Contact index method is suitable for hazard risk assessment of occupational hazards without sampling test conditions or OELs, and pre-assessment of occupational hazards of construction projects without access to analogical test data. The index method is suitable for occupational health risk assessment with available testing data and complete occupational health information.