Fatigue in industrial workers under thermal stress on extended shift lengths.

A field investigation to examine the fatigue levels in industrial workers working extended (10, 12 and 12.5 h) shifts under significant levels of thermal stress was conducted on 45 male underground miners. Studies were conducted both before and after a major change to the working-in-heat protocol used at the operation. Prior to the change, shortened (6 h) shifts had been used when thermal conditions exceeded certain values. This reduced shift length was removed and replaced with other protocols. Heart rates were continuously monitored, and a cycle ergometer was also used to assess cardiovascular fatigue over the shift. Average heart rates, as well as highest 10 and 30 min averages, and heart rate durations within various bands were analysed. No worker reported heat illness during the study. Results showed that removing the shortened shift did not increase the fatigue levels. Workers did experience fatigue, but this occurred in the first half of the shift. Evidence was found that these workers practised self-pacing.     

Fluid losses and hydration status of industrial workers under thermal stress working extended shifts

Aims: To assess whether workers under significant thermal stress necessarily dehydrated during their exposure and whether "involuntary dehydration" was inevitable, as supported by ISO 9866 and other authorities. Other objectives were to quantify sweat rates against recommended occupational limits, to develop a dehydration protocol to assist with managing heat exposures, and to understand the role of meal breaks on extended shifts in terms of fluid replacement.

Methods: A field investigation to examine the fluid consumption, sweat rates, and changes in the hydration state of industrial workers on extended (10, 12, and 12.5 hour) shifts under significant levels of thermal stress (wet bulb globe temperature (WBGT) >28°C) was conducted on 39 male underground miners. Urinary specific gravity was measured before, during, and at the completion of the working shift. Environmental conditions were measured hourly during the shift. Fluid replacement was measured during the working periods and during the meal breaks.

Results: Average environmental conditions were severe (WBGT 30.9°C (SD 2.0°C), range 25.7–35.2°C). Fluid intake averaged 0.8 l/h during exposure (SD 0.3 l/h, range 0.3–1.5 l/h). Average urinary specific gravity at start, mid, and end of shift was 1.0251, 1.0248, and 1.0254 respectively; the differences between start and mid shift, mid and end shift, and start and end shift were not significant. However, a majority of workers were coming to work in a moderately hypohydrated state (average urinary specific gravity 1.024 (SD 0.0059)). A combined dehydration and heat illness protocol was developed. Urinary specific gravity limits of 1.022 for start of shift and 1.030 for end of shift were selected; workers exceeding these values were not allowed into the workplace (if the start of shift limit was exceeded) or were retested prior to their next working shift (if the end of shift limit was exceeded). A target of 1.015 as a euhydrated state for start of shift was adopted for workforce education.

Conclusions: This study found that "involuntary dehydration" did not occur in well informed workers, which has implications for heat stress standards that do not make provision for full fluid replacement during heat exposure. Fluid replacement during meal breaks was not significantly increased above fluid replacement rates during work time, with implications for the duration and spacing of meal breaks on long shifts. Testing of urinary specific gravity was found to be a good indication of hydration status and a practical method of improving workforce awareness and understanding of this important risk factor. Approximately 10 000 dehydration tests have been conducted under the dehydration protocol in a workforce of 2000 persons exposed to thermal stress and has proved practical and reliable.

     

医务人员应激状态下应对方式的研究

目的　探讨医务人员应激状态下的应对方式及相关因素。方法　采用特质应对方式问卷 (TCSQ)、领悟社会支持量表 (PSSS)和相关因素调查表对 446名医务人员进行问卷调查。在SPSS支持下进行单因素和多元回归分析。结果　积极应对和消极应对分量表均值分别为 3 4 0 2± 5 2 4和 2 5 2 5± 5 2 5;按消极应对分值高低分组 ,2组间在生活习惯、健康状况和心理准备方面均有显著性差异 (P <0 0 1) ;经多元回归分析 ,应对倾向与心理状态、体育锻炼、家人理解、本人担心及他人支持有较高程度的相关关系。结论　应重视提高医务人员在应激状态下的心理应对能力。     

Prediction computer program for whole body temperatures and its application under various working level and thermal environmental condition combinations

We introduced a computer program developed for the numerical analysis of thermal conditions of all segments and blood circulatory systems in the human body to precisely evaluate human thermal physiological responses. In this program, a cylindrical model consisting of internal multi-layers is adapted for the segment of the human body. For the multi-layered concentric cylindrical model we adopted a new numerical solution method. By using this computer program the internal tissue temperatures, heat fluxes and blood temperatures of all segments in the human body could be calculated simultaneously. This program also included a subroutine for calculation of thermoregulatory response. This paper describes the improvements made to this computer program for simulating individual physical differences and its application to various working levels. The main points for improvement were the assigning procedures of physical characteristics of individuals and local muscle heat production. The improved computer program was used to simulate the whole body temperatures of the subjects during exercise described in Gagge, Stolwijk and Saltin (1969) were simulated. The calculated results were agreed with the measured results under the combination of the three kinds of exercise and the three types of environmental condition.     

Comparison of estimated core body temperature measured with the BioHarness and rectal temperature under several heat stress conditions

Monitoring and measuring core body temperature is important to prevent or minimize physiological strain and cognitive dysfunction for workers such as first responders (e.g., firefighters) and military personnel. The purpose of this study is to compare estimated core body temperature (Tco-est), determined by heart rate (HR) data from a wearable chest strap physiology monitor, to standard rectal thermometry (Tre) under different conditions.

?Tco-est and Tre measurements were obtained in thermoneutral and heat stress conditions (high temperature and relative humidity) during four different experiments including treadmill exercise, cycling exercise, passive heat stress, and treadmill exercise while wearing personal protective equipment (PPE).

?Overall, the mean Tco-est did not differ significantly from Tre across the four conditions. During exercise at low-moderate work rates under heat stress conditions, Tco-est was consistently higher than Tre at all-time points. Tco-est underestimated temperature compared to Tre at rest in heat stress conditions and at a low work rate under heat stress while wearing PPE. The mean differences between the two measurements ranged from ?0.1 ± 0.4 to 0.3 ± 0.4°C and Tco-est correlated well with HR (r = 0.795 – 0.849) and mean body temperature (r = 0.637 – 0.861).

?These results indicate that, the comparison of Tco-est to Tre may result in over- or underestimation which could possibly lead to heat-related illness during monitoring in certain conditions. Modifications to the current algorithm should be considered to address such issues.     

广东火力发电厂员工职业紧张状况研究

目的探讨广东火力发电厂员工职业紧张状况及其影响因素。方法采用整群抽样的方法选择广东省珠江三角洲、粤东、粤西地区共5家火力发电厂员工,采用自行设计的一般人口学问卷和职业紧张量表(OSI-R)对1 125名员工进行问卷调查,并对调查结果进行统计学分析。结果 17.6%的员工感到中度以上的职业任务过重,82.4%的员工处于适度及以下职业任务水平;19.1%的员工感到中度以上的职业紧张反应,80.9%的员工处于适度及以下职业紧张反应水平;15.0%的员工感到中度以上的应对资源缺乏,84.9%的员工处于适度以上的应对资源水平;该人群职业任务问卷(ORQ)、个体紧张反应问卷(PSQ)及个体应对资源问卷(PRQ)得分均高于国内常模得分,差异有统计学意义(P<0.05);PSQ的主要影响因素为婚姻状况、值班类型、任务冲突、工作环境、任务模糊、责任感、娱乐休闲和社会支持。结论火力发电厂员工总体职业紧张水平较适度,应对资源相对充裕,但仍有部分员工存在较高的职业紧张水平,应针对主要影响因素采取干预措施缓解其职业紧张。     

Health promotion in gas industrial workers

Health promotion in the workers of the limited liability company "Astrakhangazprom" in their working places (without discontinuing work) with the complexes of nutrients (including omega-3) enriched with vitamins, macro- and microelements, made in Russia yielded a positive therapeutic effect in improving the health status, in normalizing and improving laboratory and instrumental data, and in reducing sick cases with temporary disability. The duration of a health promotion course was 2 months.     

Inhalation exposure to isocyanates of car body repair shop workers and industrial spray painters

As part of a large-scale epidemiological study, occupational isocyanate exposure was assessed in spray-painting environments. The aim was to assess which compounds contribute to isocyanate exposure in car body repair shops and industrial painting companies, and to identify tasks with high risk of isocyanate exposure. Mainly personal task-based samples (n = 566) were collected from 24 car body repair shops and five industrial painting companies using impingers with DBA in toluene. Samples were analysed by LC-MS for isocyanate monomers, oligomers and products of thermal degradation. From the 23 analysed compounds, 20 were detected. Exploratory factor analysis resulted in a HDI, TDI and MDI factor with the thermal degradation products divided over the TDI and MDI factors. The HDI factor mainly consisted of HDI oligomers and was dominant in frequency and exposure levels in both industries. Spray painting of PU lacquers resulted in the highest exposures for the HDI factor (相似文献   

Dyslipidemia in industrial workers in hot environments

The aim of the study was to follow the rate and manifestation of dyslipidemia in industrial workers exposed to heat. One hundred and two male industrial workers exposed to heat and a control group of 102 male workers were studied. The microclimate components were followed and Wet Bulb Globe Temperature (WBGT) was calculated. The mean WGBT was 35.4 degrees C (28.4-41.7 degrees C) for the studied heat exposed work places. The lipid indices: total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C) and triacylglycerols were assayed with enzymatic tests. TC/HDL-C ratio was calculated, too. Arterial pressure, anthropometric variables, smoking, alcohol use were followed and no significant differences between the studied groups were found. Significantly higher TC, LDL-C and TC/HDL-C were found with the heat exposed industrial workers. Odds ratio indicated higher risk in heat exposed industrial workers of becoming dyslipidemic [for TC OR = 1.481 (1.097-2.002) and for LDL-C OR = 1.539 (1,123-2.111)]. Regular screening of lipid profile in heat exposed workers is recommended.     

A survey of body temperatures in the elderly and the thermal environment in nursing homes]

In order to understand the relation between body temperatures and activities in the elderly, sublingual temperatures and activities of daily living (ADL) of 92 elderly people living in nursing homes were measured in the winter of 1989 and 1990. Thermal conditions in the three nursing homes were also measured simultaneously. In two nursing homes, where most of the people of low ADL lived, room temperatures were usually kept above 20 degrees C during most of the day, while in the remaining home, where many of the people of high ADL lived, room temperatures in the morning decreased to 8 degrees C. In spite of the better thermal conditions, mean sublingual temperatures, measured in the morning, of the low ADL group were significantly lower than that of middle and the high ADL groups. Moreover, the prevalence of low body temperatures (< 35.5 degrees C) was higher in the low ADL group than in the other two groups. From these results it appears that investigations of the living environment for older people should be widened.     

Health risk behaviors, health status self-assessment and stress perception among industrial workers]

OBJECTIVE: To identify the prevalence and association among health risk behaviors, stress perception, and health status self-assessment among industrial workers. METHODS: A cross-sectional study was performed using a questionnaire previously tested in a pilot study in the State of Santa Catarina, Brazil. Data on smoking, alcohol consumption, fruit and vegetables intake, physical activity, stress perception, and self-assessment of health status were available for 4,225 workers (67.5% males and 32.5% females). Subjects were selected using a 3-stage cluster sampling (5% error margin). Statistical analysis was performed using Chi-square, and logistic regression analysis (p<0.05). RESULTS: The mean age was 29.7 years old (SD=8.6). The prevalence of smokers was 20.6%, higher among males (23.1%) than females (15.6%). The proportion of heavy drinkers was high (57.2% among males and 18.8% among females). Almost half of the subjects (46.2%) reported no leisure-time physical activity (67% females and 34.8% males). Approximately 14% of subjects reported high levels of stress and difficulty to cope with daily tasks. About 15% of the workers perceived their health status as regular or poor. Gender, age, marital status, number of children, educational level and economic status were significantly associated with the prevalence of health risk behaviors. CONCLUSIONS: Despite the limitations of cross-sectional studies, based on self-report assessments, the study results suggest a high prevalence of alcohol consumption and physical inactivity during leisure time. The observed association between gender and health risk behavior suggests that both sexes engage in risk behaviors: for men these behaviors are direct or active (smoking, alcohol consumption) and for women, they are more indirect or passive (physical inactivity, stress).     

Musculoskeletal disorders in industrial workers of Delhi

To study the musculoskeletal disorders in industrial workers in Delhi, 631 workers from 60 factories representing small and medium-sized enterprises located in Delhi were interviewed. Many (59.4%) of the workers had musculoskeletal disorders. Tailors, those working near furnaces, cooks, workers in buffing, checking and assembly work, and those working with chemicals had the most joint complaints. Cervical pain was more frequent in tailoring and packing work, whereas lumbar pain was more common in buffing, operators working on presses, those using hand and power tools, and those lifting heavy manual loads. Contract workers had less musculoskeletal morbidity than regular and temporary workers. Skilled workers also had less morbidity. Workers experiencing more job satisfaction reported fewer musculoskeletal disorders. The high prevalence of musculoskeletal disorders in workers needs urgent attention from the health and labor sectors. An ergonomic approach to prevention should be considered. The current manual load handling limits prescribed in the Indian Factory Rules potentially expose workers to back stress. It is also inappropriate to have separate load-lifting limits for men and women. Research is urgently required to determine the safe load handling limits for the Indian working population based on ergonomic principles. Until internationally acceptable safe limits are established, back pain should be a notifiable disease in India.     

Healthy volunteer effect in industrial workers.

Volunteers for epidemiological research, have lower mortality rates than non-volunteers, thereby producing a bias referred to as the "healthy volunteer effect" (HVE). Occupationally active persons have been similarly shown to have a reduced mortality relatively to the general population (the "healthy worker effect"). To determine whether a HVE exists in occupationally active persons, we followed for 8 years a cohort of Israeli male industrial employees, of whom 71.6% agreed to participate in 1985 in screening examinations for cardiovascular disease. We calculated standardized mortality ratios (SMRs) of the entire cohort relative to the general population, and compared the mortality among participants with that of the non-participants. Over 8 years follow up, SMRs were 78% for the entire cohort, 71% for participants and 99% for non-participants. Participants were older than non-participants and worked more commonly in smaller factories. A proportional hazard model indicated that after adjusting for these variables, the all cause mortality hazard ratio among participants and non-participants was 0.69 (95% CI = 0.51-0.94). During the first and last two years of the 8-year follow-up there were 39.6 and 30.0 age-adjusted deaths per 10,000 person-years among participants, and 58.6 and 51.5 respectively among non-participants. We conclude that the HVE occurs in occupationally active persons, and that it may persist for up to 8 years follow-up.     

Urinary malondialdehyde and 8-hydroxydeoxyguanosine as potential markers of oxidative stress in industrial art glass workers

Previous epidemiological studies have indicated that industrial art glass workers have increased mortality risks for certain types of cancer and for cardio-and cerebrovascular disease. To test the hypothesis that increased oxidative stress might contribute to these increased mortality risks, the urinary levels of the lipid peroxidation product, malondialdehyde (MDA), and the oxidative DNA adduct, 8-hydroxydeoxyguanosine (8OHdG) were determined in 343 workers (230 men and 113 women) from the art glass industry in the southeast of Sweden. Of the study subjects, 199 (181 men and 18 women) were engaged in the process of glass production and were regarded as exposed, whereas the remainders performed clerical, warehouse and other service work and were regarded as unexposed. One hundred and sixteen were smokers (75 men and 41 women) and 215 were non-smokers (142 men and 73 women). The findings indicate that (a) exposure to industrial art glass work per se does not cause any major oxidative stress as measured by urinary levels of MDA and 8OHdG, (b) the effects from smoking per se are limited to increased lipid peroxidation among men, and (c) joint exposure to industrial art glass work and smoking may cause increased lipid peroxidation among men and increased DNA hydroxylation among both men and women. While these findings provide no evidence for increased oxidative stress due to industrial art glass work per se, the increased 8OHdG excretion in workers who smoke may be associated with a higher risk of developing free radical-dependent degenerative disease including cancer     

Skin pathology in industrial microbiology workers]

Skin examinations of the workers engaged in three microbiologic synthesis enterprises revealed changes produced as reactions to the influence of multicomponent industrial factors. The allergic dermatoses, superficial candidiasis and epidermitis occurrence depended on the duration and degree of the contact with industrial biologically active substances. The regularities underlying transformations of the diseases from one form to another were determined. The stage based approach to the treatment and prevention of dermatoses contributed significantly to lowering their prevalence.     

Blood pressure and serum lipids in industrial workers under intense noise and a hot environment

The aim of the study was to follow the rate of high blood pressure and dyslipidemia in industrial workers in relation to experience under intense noise and a hot environment. We studied 545 male industrial workers comprising 271 subjects working under intense noise (86 to 92 dba), 159 subjects exposed to heat [wet bulb globe temperature of 35.4 degrees C (28.4-41.7 degrees C)], and a control group of 115 subjects with experience of <9; 10-19, or >20 y, which paralleled the age groups of young (< 32 y); middle-aged (33-45 y), and aged workers (> 46 y). Arterial pressure, anthropometric variables, lipid status, smoking, and alcohol use were monitored. The rate of blood pressure > 140/90 mmHg was significantly higher in noise-exposed middle-aged workers and in both exposed groups of aged workers (p < .05). The rate of dyslipidemia was significantly higher in heat-exposed middle-aged workers and in both exposed groups of aged workers (p < .05). Summing up, our data suggest that long-term work under intensive noise or in a hot environment is associated with a greater chance of becoming hypertensive and dyslipidemic. Exposure to noise was related to elevated blood pressure, whereas heat exposure was related to deviations in serum lipids.