Objective: To investigate the occupational hazard factors and exposure levels of workers during the construction of power transmission and transformation projects. Methods: Analysis and identification of occupational hazard factors were carried out for typical construction process of 6 power transmission projects and 3 substation projects in September 2018. The on-site occupational health investigation was carried out to detect and analyze the exposure levels of workers to occupational hazard factors. Results: The time weighted average concentration (C(TWA)) of crushing workers exposed to silica dust and welders exposed to welding fume in substation projects were 2.72 and 14.03 mg/m(3), respectively. The 8 h equivalent sound level results of exposure noise of carpenters in power transmission projects and crushing workers, reinforcement workers, carpenters, scaffolders, road builders in substation projects were 87.9, 92.5, 87.1, 92.5, 93.0 and 90.2 dB (A) , respectively. The 4-hour time equal energy frequency weighted vibration acceleration of hand-transmitted vibration of bricklayer in power transmission projects, bricklayer, general worker 3, road builder 1 and road builder 2 of substation projects were 5.36, 5.21, 5.28, 10.71 and 5.22 m/s(2), respectively. The effective irradiance of electric welding arc light of welders' limbs in power transmission projects and substation projects were 401.19, 319.68 μW/cm(2), respectively. All of the above exceeded the requirements of occupational exposure limits. The occupational radiation levels and exposure limits of hazardous chemical factors met the requirements of each post. Conclusion: During the construction of power transmission and transformation projects, the exposure levels of occupational hazard factors in multiple posts exceed the standard. The main responsibility of employers for occupational disease prevention and control should be implemented, and targeted comprehensive measures should be taken to reduce the exposure levels of occupational hazard factors of workers.
Dust ; Humans ; Occupational Diseases ; Occupational Exposure/analysis* ; Occupational Health ; Welding

OBJECTIVETo explore the quantitative relationship between the dust mass concentration and fiber number concentration of refractory ceramic fibres.

METHODSA typical refractory ceramic fiber plant was selected as the study site. Fifty-three paired samples of total dust mass concentration and fiber number concentration were collected using the long-time fixed site mode. The total dust mass concentration was measured according to the GBZ/T 192.1-2007 (Measurement of dust in the air of workplace, part 1: Total dust concentration). Membrane filter method/phase-contrast optical microscopy was used to determine the fiber number concentration. Univariate analysis was used to describe the distribution of the two concentrations and their ratio. Spearman rank correlation, as well as linear regression, logarithmic curve, polynomial, power function, and exponential curve model, were used to explore the relationship between the two concentrations. Results The range of the total dust mass concentration (x) was 0.45-13.82 mg/m3. The range of the fiber number concentration (y) was 0.01-1.04 f/ml. The range of the ratio (x/y) was 4-158. All of the three parameters did not follow normal distribution (P<0.000 1). The two concentrations showed a positive correlation (r,=0.705 22, P< 0.000 1). All the coefficients of determination (R2) of linear regression, logarithmic curve, polynomial, power function, and exponential curve model were relatively low. The trinomial curve model had the highest R2 (0.6848) and the fitted equation was y=-0.001, 1x+0.010 4x2+0.101 4x-0.055 1.

CONCLUSIONThere is a positive correlation between the total dust mass concentration and fiber number concentration of refractory ceramic fibers. However, there is no fixed regression relationship between the two concentrations, and neither is a definite coefficient which can be used to convert each other. The two concentrations cannot be replaced by each other.

Air Pollutants, Occupational ; analysis ; Ceramics ; Dust ; analysis ; Occupational Exposure

Environmental Monitoring ; Humans ; Occupational Exposure ; Toluene ; analysis

Environmental Monitoring ; methods ; Inhalation Exposure ; Occupational Exposure ; analysis ; Workplace

Welding operations are widely present in the manufacturing production process, involving a large number of occupational groups, and are the key occupations where work injuries and occupational diseases occur in China. For different welding processes and welding materials, the content and focus of occupational health monitoring are different. At present, the item of occupational health examination in welding operation is in poor consistency with the on-site exposure of occupational hazard factors, and it is mainly concentrated in the stage of disease development, which can not reflect the early health damage caused by welding dust exposure in time. The emergence of biomarkers of welding dust can make up for this defect. Therefore, it is of great significance to describe the current situation of occupational health monitoring of welding dust and summarize the research progress of related biomarkers for the early prevention of diseases caused by welding dust and the practice of occupational health monitoring.
Occupational Health ; Welding ; Occupational Exposure/analysis* ; Dust/analysis* ; Biomarkers ; Air Pollutants, Occupational/analysis*

Objective: To explore the occupational hazards caused by three kinds of welding operations, and to provide data support for individual protection. Methods: In October 2020, the welding fumes, metal elements and welding arc generated by three welding operations of argon gas shielded welding (JS80 welding wire) , manual welding (ZS60A welding rod) and carbon dioxide shielded welding (907A flux cored wire) were collected and measured in the welding laboratory. The samples were analyze and compare in the laboratory, and the differences of the occupational hazard factors of the three welding operations were judged. Results: The concentration of welding fume produced by carbon dioxide shielded welding, manual welding (ZS60A electrode) , and argon gas shielded welding (JS80 welding wires) were 6.80 mg/m(3), 6.17 mg/m(3), and 3.13 mg/m(3), respectively. The effective irradiance of the welding arc outside the welding mask from high to low is manual welding (ZS60A electrode) , carbon dioxide shielded welding (907A flux-cored welding wire) , and argon shielded welding (JS80 welding wire) , respectively 1 010.7, 740.9, 589.5 μW/cm(2). The long-wave ultraviolet UVA intensity generated by argon shielded welding (JS80 welding wire) is the largest, which is 1 500 μW/cm(2). The content of Mn in the three welding operations is the highest, and JS80 welding wire has the highest Mn content of 128493.2 mg/kg. 907A flux cored wire has the highest Ti content, which is 24355.5mg/kg. The electrode ZS60A has the highest Cu content, which is 24422.12 mg/kg. Conclusion: The intensity of occupational hazards is different in the three kinds of welding operations, so the methods of personal protective equipment, field exposure assessment and health monitoring should be more targeted.
Air Pollutants, Occupational/analysis* ; Argon/analysis* ; Carbon Dioxide/analysis* ; Gases/analysis* ; Occupational Exposure/analysis* ; Welding/methods*

OBJECTIVETo explore the present state of occupational hazards and health status of workers in the automobile maintenance industry.

METHODSThe monitoring results of occupational hazards in 25 automobile maintenance companies, occupational health examination results of 751 male workers in 63 automobile maintenance companies, and physical examination results of 205 male students in one Research Institute were statistically analyzed in 2012.

RESULTSThe concentrations of benzene, toluene, xylene, ethyl acetate, and butyl acetate in the workplace were 0.3∼21.7, 0.4∼40.3, 0.4∼84.8, 1.9∼34.3, and 0.7∼516.7 mg/m(3), respectively; benzene concentration exceeded the upper limit in two workplaces, and butyl acetate concentration exceeded the upper limit in one workplace. The intensity of noise was 70.3∼ 91.3 dB (A) and exceeded the upper limit in one workplace. The prevalence of blood system involvement in spray painters was 15.6%, significant higher than that of the control group (P < 0.05). High-frequency hearing loss was detected in 53.9%of all metalers. Logistic regression analysis indicated that blood system involvement was not correlated with age and working years in spray painters; high-frequency hearing loss in metalers was positively correlated with age, but not correlated with working years.

CONCLUSIONThe status of occupational hazards in the automobile maintenance industry should not be neglected, and the management of noxious positions and personal protection should be strengthened in enterprises.

Adult ; Air Pollutants, Occupational ; analysis ; Automobiles ; Humans ; Male ; Occupational Diseases ; epidemiology ; Occupational Exposure ; analysis ; Young Adult

This article investigated an occupational chronic benzene poisoning incident that occurred in a sealing material factory in Hebei Province in September 2019, analyzed the clinical data of workers, to explore the causes of occupational chronic benzene poisoning, and summarize the diagnosis and treatment characteristics and treatment outcome. According to GBZ 68-2013 "Diagnosis of Occupational Benzene Poisoning", a total of 12 cases of occupational chronic benzene poisoning were diagnosed among the 20 workers, including 2 cases of occupational chronic mild benzene poisoning, 7 cases of moderate benzene poisoning, and 3 cases of severe benzene poisoning. Both mild and moderate poisoning patients had recovered after treatment. Severely poisoned patients had recovered more slowly, and the white blood cell count was still 2.0×10(9)-3.0×10(9)/L during the 1-year follow-up. This benzene poisoning incident was caused by illegal operations. The responsibility of the employer, the supervision of the administrative agency, and the awareness of personal protection of employees should be strengthened to avoid or reduce the occurrence of poisoning incidents and ensure the health of workers.
Accidents, Occupational ; Benzene/analysis* ; Chronic Disease ; Humans ; Leukocyte Count ; Occupational Diseases/epidemiology* ; Occupational Exposure/analysis* ; Poisoning

Objective: To investigate the detection of suspected occupational diseases and occupational contraindications for benzene workers in Tianjin. Methods: In June 2020, the occupational health inspection data of 16113 benzene workers in 514 enterprises with benzene hazards in 16 municipal districts in Tianjin from January to December 2019 were included in the analysis. Enterprise information included the employer's region, economic type, industry classification and enterprise scale. Occupational health inspection data for benzene workers during their on-the-job period included routine inspection indicators and benzene special inspection indicators. Multivariate unconditional logistic regression was used to analyze the relationship between personal general information, occupational history, enterprise information and suspected benzene poisoning and occupational contraindications of benzene workers. Results: There were 16073 benzene workers in the normal group and 24 in the suspected benzene poisoning group. The detection rate of suspected benzene poisoning in females was higher than that in males (χ(2)=8.26, P=0.004) . There was no significant difference in the detection rates of suspected benzene poisoning among different dimensions such as age, length of service, occupational health inspection institution location, employer location, industry classification, economic type, and enterprise scale (P>0.05) . There were 16073 benzene workers in the normal group and 16 in the benzene contraindication group. The detection rate of benzene contraindications for workers in suburban areas where occupational health inspection institutions were located was higher than that in urban areas (χ(2)=9.71, P=0.002) , and there was no significant difference in the detection rates of contraindications for benzene in other dimensions (P>0.05) . Multivariate logistic regression analysis showed that female benzene workers were more likely to detect suspected benzene poisoning (OR=3.53, 95%CI: 1.57-7.94, P=0.002) ; benzene workers who received physical examination in suburban occupational health inspection institutions (OR=5.81, 95%CI: 1.94-17.42, P=0.002) , the employer's area was in the suburbs (OR=9.68, 95%CI: 1.23-76.07, P=0.031) , and female workers (OR=3.07, 95%CI: 1.13-8.37, P=0.028) , it was easier to detect occupational contraindications. Conclusion: Female benzene workers with employers located in the suburbs have a higher risk of detecting occupational contraindications, and women are more likely to detect suspected benzene poisoning. The management of benzene operations in the production environment of enterprises in the suburbs of Tianjin and the occupational health monitoring of female workers should be strengthened.
Benzene/analysis* ; Female ; Humans ; Industry ; Male ; Occupational Diseases/epidemiology* ; Occupational Exposure/analysis* ; Occupational Health

Objective: To evaluate the occupational health risk of organic solvents in major posts of printing industry, and to provide technical reference to take targeted risk control measures. Methods: In January 2021, the contact ratio method was used to assess the occupational health risk of organic solvents in the major posts of 84 printing enterprises in Shantou, and Monte Carto method was used to estimate the probability distribution of risk levels in the majorpostsin January 2021. Results: The highest probability of risk assessment in printing and membranecovering post is Level 4 (high risk) , which are 76.2% and 67.6% respectively; the highest probability of simulation evaluation result in oil blending, dispensing and cleaning post is Level 3 (medium risk) ; and the simulation evaluation result in glueing post are mostly Level 3 (medium risk) and Level 4 (high risk) , the probability of which are 45.7% and 54.3% respectively. Conclusion: The occupational health risk of organic solvents in the major posts is generally middle-high risk level, and then the occupational health risk control of organic solvents in major posts of printing industry should be strengthened.
Air Pollutants, Occupational/analysis* ; Industry ; Occupational Exposure/analysis* ; Occupational Health ; Risk Assessment ; Solvents