Stress on and off the job as related to sex and occupational status in white-collar workers

Sixty healthy non-smoking white collar employees, aged 30–50, from a large corporation in Sweden participated in the study. There were four groups: 15 male and 15 female middle managers, 15 male and 15 female clerical workers. Each participant was examined individually with regard to cardiovascular and neuroendocrine functions and self-reports for 12 consecutive hours under each of two conditions: (1) a normal day at work (9 a.m.–5 p.m.) and after work (6–9 p.m.), and (2) for the same time period during work-free conditions at home. In addition, everyone was given a videotaped type A-interview and a general health check-up including blood-lipid determination. Attitudes towards work, total workload (including responsibilities outside the paid work) and sex role identity were examined by questionnaires. As expected, all groups showed a moderate increase in cardiovascular and neuroendocrine activity during the day at work. After work, however, interesting group differences emerged, suggesting slower unwinding in female managers. Differences related to occupational level and/ or sex were found for autonomy and social support at work, competitiveness, sex role and reported conflict between demands from paid work and other responsibilities. The stress profile of the female managers was considered in terms of possible long-term health risks.     

Cardiovascular Load During Summer Work of Two Age Groups of Van-Rickshaw Pullers in West Bengal,India

Van-rickshaw is a popular mode of transport of people and merchandise in developing countries. The purpose of this study was to assess the effect of age on cardiovascular load of van-rickshaw pullers in the summer season (March-June) in real situations. In 142 participants, divided into 2 age groups (25-40 and 41-55 years), cardiovascular load was assessed on the basis of working and partial recovery heart rate (HR), predicted maximal HR, working maximal HR, average working HR, percentage of reserved HR, sum of recovery heart beats, percentage of recovery, relative and net cardiac cost, etc. Except for percentage of recovery, all parameters differed significantly between the groups and were significantly correlated with age. As this activity is very stressful, it places a heavy demand on the cardiovascular system. Therefore, age is an important factor for sustainability of the work, especially in a hot environment. Some ergonomic interventions are necessary to reduce cardiovascular load.     

The moderating role of task characteristics in determining responses to a stressful work simulation

Two experimental studies were conducted to examine whether the stress‐buffering effects of behavioral control on work task responses varied as a function of procedural information. Study 1 manipulated low and high levels of task demands, behavioral control, and procedural information for 128 introductory psychology students completing an in‐basket activity. ANOVA procedures revealed a significant three‐way interaction among these variables in the prediction of subjective task performance and task satisfaction. It was found that procedural information buffered the negative effects of task demands on ratings of performance and satisfaction only under conditions of low behavioral control. This pattern of results suggests that procedural information may have a compensatory effect when the work environment is characterized by a combination of high task demands and low behavioral control. Study 2 (N=256) utilized simple and complex versions of the in‐basket activity to examine the extent to which the interactive relationship among task demands, behavioral control, and procedural information varied as a function of task complexity. There was further support for the stress‐buffering role of procedural information on work task responses under conditions of low behavioral control. This effect was, however, only present when the in‐basket activity was characterized by high task complexity, suggesting that the interactive relationship among these variables may depend on the type of tasks performed at work. Copyright © 1999 John Wiley & Sons, Ltd.     

Changes in the peripheral blood flow in legs in response to the cold: own studies using plethysmography

The thermal environment in the workplace is an important factor which affects workers’ health. During 2011 in Poland, 14,781 workers were exposed to a cold working environment, i.e., 3.8% of persons employed in hazardous work conditions. The aim of this study was to determine the cardiovascular response to continuous (4 °C for 60 min) and intermittent (10 min at 4 °C and 10 min at room temperature alternately) exposure to the cold in 30 healthy men aged 20–27 years. Peripheral blood flow was assessed with impedance plethysmography. Heart rate and arterial blood pressure were monitored with the Holter system. Having assessed the results, it is difficult to say which kind of exposure has a more severe impact on the cardiovascular system. Longer observation and a more detailed analysis would be necessary (e.g., Doppler echocardiography).     

矿工心理因素、工作压力反应和不安全行为关系研究

为研究在巨大工作压力下,矿工的心理因素与工作压力反应和不安全行为的关系,以问卷的形式调查陕西省2家具代表性煤矿的工人,分别以矿工的心理因素、工作压力反应和作业过程中的不安全行为作为外生变量、中介变量和内生变量,构建心理因素、压力反应和不安全行为的结构方程模型。通过对调研数据处理与分析,得出如下结论:本研究中的4项心理因素,性格因素、心理素质、注意力和工作态度显著影响不安全行为的发生;性格因素、心理素质和注意力对压力反应有显著影响;工作态度与煤矿工人的压力反应的关系不显著;性格因素、心理素质、注意力和工作态度通过影响矿工的压力反应,间接影响矿工的不安全行为。     

The effect of age on safety and work practices among domestic trash collectors in Québec

Aging is associated with physiological modifications which may affect work activities. Trash collectors' work at the back of garbage trucks is both solitary and strenuous, and it therefore appeared relevant to investigate the effects of aging in these workers. The working hypotheses were that older trash collectors work at different speeds and adopt different work practices than do younger ones, and that these differences affect the frequency and nature of accidents and mishaps in the two age groups. A multidisciplinary approach, incorporating statistics, ergonomics, and social sciences, was adopted. Workers at least 35 years old were compared to younger workers, using data from three sources: accident data (176 cases), observation of 17 trash collectors during 36 collection trips (more than 150 hours of observation), and semi-directed interviews of 11 trash collectors. Analysis indicated that older trash collectors: (1) adopt a slower work rhythm; (2) are helped more often by teammates; (3) are involved less frequently in mishaps; (4) declare themselves less fatigued and to have suffered fewer accidents; and (5) are proportionally more likely to be victims of slips, falls, and back injuries resulting from movements under load. There was no observed difference, however, between the work practices adopted by the two groups of workers or the length of work absences following accidents.     

Why seeking feedback from diverse sources may not be sufficient for stimulating creativity: The role of performance dynamism and creative time pressure

We explore how the impact of seeking feedback from different sources (i.e., feedback source variety) on employee creativity is shaped by perceptions of the work environment. Specifically, we argue that two contextual factors, namely, performance dynamism (Study 1) and creative time pressure (Study 2), moderate the relationship between feedback source variety and creativity such that under conditions of high performance dynamism and low creative time pressure, individuals benefit from diverse feedback information. In Study 1 (N = 1,031), the results showed that under conditions of high performance dynamism, the relationship between feedback source variety and self‐reported creativity was nonlinear, with employee creativity exponentially increasing as a function of feedback source variety. Similarly, in Study 2 (N = 181), we found that under conditions of low creative time pressure, the relationship between feedback source variety and employee creativity was nonlinear, with supervisor‐rated creative performance exponentially increasing at higher levels of feedback source variety. Such results highlight that the relationship between feedback source variety and creative performance is affected by the perceptions of the work environment in which feedback is sought.     

Perceived Discomfort and Electromyographic Activity of the Upper Trapezius While Working at a VDT Station

Ten female participants performed work at a video display terminal (VDT) station over a whole working day. Subjective local muscular fatigue was evaluated by means of the Category Ratio 10 scale. Electromyographic activity of the upper right and left trapezius was measured. A comparison was made between 5 participants who had previous complaints and 5 participants who reported no musculoskeletal problems in the shoulder-neck region. The subjective scores for the shoulder differed significantly between the two groups, being higher for the group with complaints. Both groups showed a decrease in discomfort after the lunch break. The activity of the trapezius increased significantly for both groups, in a more pronounced way for the group with disorders. Although it is found in literature that VDT work is a task with very low static loads, it seems from this study that the EMG activity increase can be an indication of muscle fatigue: More effort was required to accomplish the same VDT task at the end of the day.     

自吸过滤式呼吸器对人体呼吸模式的影响

测定了在中等（100W）和高等（155W）劳动强度下,8名受试者佩戴5种自吸过滤式呼吸器（呼吸阻力及死腔不同）从事踏车运动时的呼吸模式变化。结果表明：口腔压力波动和外呼吸功因呼吸器而显著增加;随着呼吸负荷的增加,呼气压及吸气压相应增大;在呼吸负荷较大的情况下,呼气压及吸气压的增大更加显著;随运动负荷的增加,呼吸负荷对呼吸压的影响更加明显。     

高压注入和等压扩散条件下N2置换煤中CH4的研究

为探究注气置换抽采煤层瓦斯的效果,揭示注弱吸附性气体N2在等压扩散和高压注入2种条件下置换煤中CH4的机理,采用自行搭建的含瓦斯煤多元气体置换试验装置,开展等压扩散和高压注入2种条件下注N2置换煤中CH4的试验研究.研究结果表明:在注N2量相同的条件下,等压扩散置换量始终高于高压注气置换量,在等压扩散下N2置换CH4效...     

Self-ignition of tetrafluoroethylene induced by rapid valve opening in small diameter pipes

This work investigates the ignition of tetrafluoroethylene induced by the adiabatic compression that can arise by activating a high speed valve separating two portions of a pipeline with a high pressure difference. In the tests performed the high pressure zone contained tetrafluoroethylene at pressures between 15 and 30 bar. For the low pressure zone, experiments with nitrogen, air and tetrafluoroethylene were carried out. The pressure range in the low pressure zone was comprised between 0.05 and 1 bar. The pipe diameters analyzed were 15 and 20 mm. For the analyzed geometries, special conditions were required in order to reach reproducible ignitions, namely air at temperatures of at least 105 °C had to be present in the compression pipe. Furthermore, a minimum length of the compression pipe had to be used. The current work describes the experimental setup employed for the tests and discusses the achieved results. Numerical simulations were performed in order to clarify unexpected findings.     

Some consequences of labor–management negotiations: Laboratory and field studies

The stress associated with labor-management negotiations is investigated in two longitudinal studies. In Study 1, changes in anxiety and blood pressure following a simulated negotiation exercise are assessed. The sample consisted of 49 advanced undergraduate Industrial Psychology students, divided into experimental (n = 24) and control (n = 25) groups. The experimental group engaged in a simulated labor–management negotiation, whereas the control group participated in a class discussion session. Anxiety and blood pressure levels of both groups were tested before and after the manipulation. Statistically controlling for pretest differences, the experimental group yielded more negative changes in anxiety and blood pressure levels than the control group from pretesting at posttesting. In Study 2, moderators and psychological consequences of participation during in vivo labor–management negotiations were studied. Data were collected from 96 industrial relations (IR) practitioners immediately before negotiations and three months later. Using moderated multiple regression, negatively perceived IR stress predicted negative changes in psychological well-being. Family support moderated the relationship, while personality hardiness yielded a negative buffering effect on this relationship. Explanations of the findings are discussed and implications for future research are suggested.     

大气压力对细水雾灭火系统泵组流量特性及效率的影响

柱塞泵是泵组式细水雾灭火系统的关键部件,它是细水雾喷头实施喷雾的供水源和压力驱动源.为研究大气压力,特别是高海拔低气压环境对柱塞泵流量特性及效率的影响,通过在合肥及拉萨两地的对比试验,给出了环境压力与柱塞泵流量特性及效率的关系.结果表明,大气压力减小使柱塞泵的流量减小,因此,在高原低气压环境下使用柱塞泵,应采用增加柱塞泵进口压力的措施,以保证泵组式细水雾灭火系统的设计性能;不同大气压力下泵组的效率无明显变化,即大气压力对泵组的效率无明显影响.     

Cardiovascular Strain of Sawmill Workers in South-Western Nigeria

This study aimed to assess cardiovascular strain during sawmilling operations in terms of physical workload, based on heart rate changes. We measured resting and working heart rates and calculated cardiovascular load (%CVL), cardiovascular strain (%CVS) and relative heart rate (%RHR) in 35 sawmill workers. Based on heart rate only, the work in sawmills was classified as very heavy and extremely heavy. Similarly, a high-level category was recorded for %CVL and a very high range for %CVS. Thus, the workload in sawmill operations is usually very high and can lead to physiological strain of the workers. There is a need to redesign the work content of this occupation to prevent excessive strain in the workers, as this will increase their productivity and reduce their health risk.     

Investigation of the use of a closed pressure vessel test for estimating condensed phase explosive properties of organic compounds

Following the indications of earlier work, the use of a closed pressure vessel test (a mini-autoclave system) to estimate the explosive properties of organic compounds has been investigated. The dependent variable was an explosivity ranking derived from the results of a propagation of detonation test, a heating under confinement test and a deflagration test. Tentative criteria have been derived to allow the following conclusions:• Not detonable• Not Class 1• No explosive properties with respect to transport classificationThe criteria are based upon the maximum rate of pressure rise observed in the mini-autoclave and the temperature at which this occurs. They offer a more efficient screen than the decomposition energy criteria which are currently used for initial assessment of explosive properties. The importance of event temperature suggests that existing classification tests may be underestimating heating under confinement and deflagration hazards. In this case, maximum rates of pressure rise from a closed pressure vessel test might be a better basis of classification, at least for supply if not transport. Further work is necessary to test the proposed screening criteria and to assess the use of a closed pressure vessel test as a means of classification.     

Work Content and Eye Discomfort in VDT Work

A questionnaire study of Swedish public employees with frequent and different types of VDT work (n = 2,025) was conducted. Eight different kinds of eye discomfort were examined, and an additive index was constructed. Eye discomfort was statistically related to aspects of work organization. The highest levels of discomfort were reported by computer-aided design (CAD), data entry, and word processing groups; groups with mixed VDT tasks displayed the lowest level of symptoms. Time spent at a VDT, low degree of work control, time pressure, and high pace of work were all associated with relatively high levels of eye discomfort. There was significant interaction between experience of stress and time spent at a VDT with respect to both the eye discomfort index and three specific symptoms (itching, gritty feeling, and dryness). Whereas dryness, smarting, and itching of the eyes seem most strongly related to work conditions, redness and watery eyes seem most weakly related.     

Stress reactions in computerized administrative work

Ninety-five white-collar workers employed by an insurance company using visual display units (VDU) connected by telecommunication to a central computer filled in a questionnaire concerning psychosocial stressors in connection with work at the VDU. Eleven persons with extensive and ten with no work at VDUs were also studied during regular work, during breakdown of machinery, and in their leisure time. Self-reports on mood and alertness were recorded along with blood pressure, heart rate, and excretion of adrenaline and noradrenaline. Results indicate that (1) stress and mental strain occurred in association with delayed response times in the computer system and unpredicted interruptions of system operation, (2) such a temporary interruption caused an increase of blood pressure and adrenaline excretion, (3) complaints of stress and strain were repotted mainly by data-entry staff, (4) data-entry groups displayed a higher level of physiological arousal during post-work hours than a control group, and (5) that a majority of those who worked continuously at a VOU reported physical discomfort within 1.5 hours. It is concluded that stress and strain in computerized work may be counteracted at the technological and the organizational level: by reducing the duration and frequency of breakdowns, by reducing response times in the system, and by eliminating pure data-entry tasks.     

Experimental study on the characteristics of the strong boiling induced by pressure relief at the top of vertical vessels

In this study, the strong boiling process of a superheated liquid induced by pressure relief at the top of a vertical vessel was experimentally investigated. Through monitoring the response of the pressure at the top of the vessel and the full field morphology of the two-phase flow, the correlations between the pressure rise and the two-phase flow as well as the trend of the characteristic pressure values under different discharge areas and filling rates were analyzed. The results indicated that the expansion of the mist-like two-phase flow, which was generated due to the strong boiling and bubble collapse, was the direct reason for the two pressure rebounds at the top of the vessel. And under the effect of the intermittent expansion of the two-phase flow, the pressure rising rate in the second rebound stage fluctuated. When the discharge area changed, the characteristic pressure values presented different relativeness under different filling rates. In addition, the average pressure rising rate during the second pressure rebound process presented an exponential growth with the increase of the discharge area, and the exponent coefficient decreased with the increase of the liquid filling rate.     

基于脑电数据的管制架次对管制员疲劳影响研究

为量化研究管制区域内飞机架次的时空变化对管制员疲劳的影响,设计相应测试方案进行试验研究。有针对性地选取20名在职管制员分别在大、小夜班的班前和班后进行试验,采集完成不同流量等级下雷达模拟机任务过程中的管制员的脑电(EEG)信号数据,从数据中提取疲劳指标值,运用SPSS20.0软件统计分析指标值,根据管制员的岗龄将其分成2组进行比较,线性拟合班前班后的管制员疲劳指标值。结果表明:岗龄≥10年的管制员疲劳指标值及其波动性明显低于岗龄<10年的管制员;班前管制员疲劳指标值随管制架次的增加中后期呈下降趋势;班后管制员的疲劳指标值随管制架次的增加而增长,随时间呈3次曲线变化。     

Changes in production concepts emphasize problems in work-related well-being

Recurrent changes in work life, although necessary for competitive and financial reasons, seem to increase time pressure, stress, health complaints and safety problems of workers. The dynamics of recent workplace transformations are not sufficiently understood from the perspective of everyday work, particularly by health and safety experts. In this paper, the Activity Theoretical Approach is used to reconceptualize work-related well-being in situations of rapid change. The key concepts in this paper are production and service concepts and their asynchronies. Many asynchronies were observed in the analysis of the two cases of different types of organizations. These asynchronies are a major challenge for experts on well-being, especially since continuous change has now become an inseparable part of work life.