Investigations of mood and workload in health care settings have focussed primarily on nurses and junior doctors. Given the critical shortfall in the Australian midwifery workforce, and the specialised nature of midwifery as an occupation, it is important to understand how mood and workload are experienced by midwives. Twenty midwives (18F, 2M) in an Australian metropolitan hospital completed logbooks assessing daily fluctuations in subjective mood and workload. Participants also provided information about history of psychopathology and sleep quality. Results revealed that midwives were relatively stable in terms of mood but did experience increased fear and decreased happiness when at work. Further, workload factors significantly predicted mood at work. Specifically, when participants felt that their work was more demanding and frustrating and required more effort, or when they felt that they could not accomplish all that was expected, mood was negatively influenced. This supports the connection between workload and negative mood change in healthcare. Given the potential for mood to influence a multitude of functions relevant to safety, performance and psychosocial wellbeing it is important to understand the factors which influence mood, particularly in light of the current shortfall in the Australian healthcare workforce.
The aim of this study was to design ergonomically improved shift schedules for nurses in primary health care shift work in order to enhance their health and well-being. The main change made was the reduction of quick returns (i.e., no more morning shifts immediately after an evening shift) in order to ensure more recovery time between work shifts. Six municipal hospital units participated in the intervention. Our aim was to maintain or improve the well-being and work ability of aged workers. The subjects (n=75) were divided into three age groups: 20-40, 41-52, and 53-62 yr. The introduction of more recovery time between evening and morning shifts significantly improved the subjects' sleep and alertness, well-being at work, perceived health, and leisure-time activities independently of their age. The effect on social and family life was also positive. Working in shifts was the most disruptive for the youngest group of nurses. The Work Ability Index score depended on the age group: it was lowest among the oldest age group, and did not change during the intervention. Ergonomic working time arrangements show positive effects on the well-being of health care workers of all ages.
There is evidence that work schedules may influence rates of unhealthy behaviors, suggesting that addressing work schedule challenges may improve health. Health Risk Assessment (HRA) survey responses were collected during 2000-2008 in a multinational chemical and coatings manufacturer. Responses of 26,442 were sufficiently complete for analysis. Rates of smoking, lack of exercise, moderate to high alcohol use, obesity (BMI≥30), and short sleep duration were compared by work schedule type (day, night, or rotating shift) and daily work hours (8, 10, or 12 h). Prevalence rate ratios (RRs) were calculated, adjusting for age group, sex, marital/living status, job tenure, and occupational group. The reference group was 8-h day shift employees. Overall prevalence rates were: sleep duration of 6 h or less per night 47%, smoking 17.3%, no exercise 22.0%, BMI≥30 28.3%, and moderate to heavy alcohol consumption 22.2%. Statistically significant RRs include the following: Short sleep duration: 10 h rotating shift (RR=1.6), 12 h day and 12 h rotating shifts (RR=1.3); Smoking: 12 h day and rotating shifts (RR=1.6), 10 and 12 h night and 8 h rotating shift (RR=1.4); No exercise: 8, 10, and 12 h rotating shifts (RR=1.2 to 1.3), 12 h day schedules (RR=1.3). Obesity (BMI≥30): 8 and 10 h night shifts (RR=1.3 and 1.4, respectively).
The global mining industry keeps expanding, and projects are often started in areas previously considered too remote. Due to worker beliefs about safety, and the diversity of cultures in remote projects, the measurement and management of human fatigue is complex. This paper reports on five studies from companies in Kalimantan, the Indonesian part of the island of Borneo, where workers had been killed in likely fatigue-related accidents. Mixed-method approaches, involving qualitative, semi-quantitative, and quantitative measures were used. Participants were 20-45 yr old, had homes of 4.7 people (SD ± 1.8), shared income outside of the house in 80% of cases, travelled ≤3 d each-way between blocks of shifts. A major output was a set of camp standards to help ensure recovery sleep. Another requirement identified was access to leave when family members died, since not attending death ceremonies caused a lot of stress and made recovery and safe work less possible. Demanding work conditions and long work hours were also problematic in some operations. Safety systems should better consider fatigue in accidents/incidents and link its data with hours of work information. The interaction of cultures, stress, sleep, fatigue, safety and individual differences must be more effectively addressed in remote mining camps.
The present study reviews the literature on suicide prevention programs conducted in the workplace and other settings, namely school, the community, medical facilities, jail, and the army, by conducting an electronic literature search of all articles published between 1967 and November 2007. From a total of 256 articles identified, various contents of suicide prevention programs were determined, and in 34 studies, the effect of programs was evaluated. A review of the literature reveals that the common contents of suicide prevention programs in the workplace and other settings are education and training of individuals, development of a support network, cooperation from internal and external resources, as well as education and training of managers and staff. Although the characteristic contents of suicide prevention programs at the workplace aimed at improving personnel management and health care, screening and care for high-risk individuals, as well as improvement of building structures, were not described. Although a reduction in undesirable attitudes and an increase in mental health knowledge and coping skills in the workplace are in agreement with findings in other settings, suicide rate, suicide-associated behavior, and depression, which were assessed in other settings, were not evaluated in the three studies targeting the workplace.
In occupational hygiene, activated carbon produced from coconut shell is a common adsorbent material for harmful substances including organic vapors due to its outstanding adsorption capacity and cost advantage. However, moisture adsorption of the carbon generally decreases the adsorption capacity for organic vapors. In a previous report, we prepared several coconut shell activated carbons which had been preconditioned by equilibration with moisture at different relative humidities and measured the breakthrough times for 6 kinds of organic vapor, in order to clarify the effect of preliminary moisture content in activated carbon on the adsorption capacity in detail. We found that the relative percent weight increase due to moisture adsorption of the carbon specimen had a quantitative effect, reducing the breakthrough time. In this report, we carried out further measurements of the effect of moisture content on the adsorption of 13 kinds of organic vapor, and investigated the relationship between moisture adsorption and the reduction of the breakthrough time of activated carbon specimens. We also applied the data to the Wood's breakthrough time estimation model which is an extension of the Wheeler-Jonas equation.
Human performance on color discrimination in visual display terminals may be affected by illuminant colors, the level of ambient illumination and background colors of the monitor. Few studies have focused on this topic. This study investigated human color discrimination ability in a simulated control room. Ten subjects were recruited as participants to perform a series of experimental tasks. A complete factorial (2 × 3 × 3) within-subject design was used. The independent variables were three illuminant colors (red, blue, and white), two ambient illumination levels (50 lux and 300 lux), and three background colors (black, blue and brown); the three dependent variables were the color discrimination ability (error scores), completion time and subject preference. The results showed that the illuminant colors and the screen background colors both significantly influenced human color discrimination ability (p<0.01). The result of this research can be used in control room design when considering the effect of color.
Visceral obesity is associated with the clustering of metabolic risk factors and the incidence of cardiovascular events. However, the association between the waist circumference values and the metabolic risk factors has not been fully established in Japanese middle-aged subjects. We examined the data from 6,033 Japanese middle-aged subjects aged 40-59 yr (4,599 male and 1,434 female). Metabolic risk factors such as high blood pressure, dyslipidemia, and glucose intolerance were identified according to the diagnostic criteria for metabolic syndrome in Japan. Numbers of metabolic risk factors were significantly associated with the waist circumference values in both male and female subjects. The prevalence of subjects with multiple (two or more) metabolic risk factors was 29.7% and 7.4% in male and female, respectively. According to receiver operating characteristic analysis, the cut-off values of waist circumference with the maximal sensitivity plus specificity to predict the presence of multiple metabolic risk factors were 86 cm and 81 cm in male and female, respectively. These values were in agreement with the diagnostic criteria for metabolic syndrome in Japanese male, but not in female. In conclusion, the waist circumference values can predict the presence of multiple metabolic risk factors in Japanese middle-aged subjects.
Much concern has been raised over the health consequences of workers exposed to carbon nanotubes. In order to characterize multi-wall carbon nanotubes (MWCNT) suspended in a phosphate-buffered saline containing 0.1% Tween 80 for an intratracheal instillation study. Length and width distributions of the MWCNT fibers, dispersion of MWCNT in the suspension and in the lung tissue and the MWCNT contents of metal impurities were investigated. Arithmetic mean length and width of the MWCNT fibers as measured on scanning electron microscope (SEM) photographs were 5.0 μm and 88 nm, respectively, and fibers longer than 5.0 μm were 38.9% of all fibers measured. Dynamic light scattering size measurement revealed that 5-min ultrasonication, together with addition of Tween 80 into the suspension, decreased the hydrodynamic diameters of the agglomerated MWCNT to those of finer particles below 1.0 μm. SEM observation showed good dispersion of MWCNT in the suspension, and in the alveoli on Day 1 after instillation. Concentration of iron, chromium and nickel in the MWCNT were 4,400, 48 and 17 ppm (wt/wt), respectively, all of which were below levels that would elicit positive pulmonary toxic responses to these metals. The results suggest that well-dispersed, long and thin MWCNT fibers exhibit asbestos-like pathogenicity in the lung.
“Lockout” is an important method for hazardous energy control to protect humans working at a place where they may be injured by unexpected release of hazardous energy. Actually, this administrative control is used in order to compensate for the incompleteness of the ZMS (Zero Mechanical State). This paper proposes the basic requirements for the “Lockout” used for machine maintenance work by applying the “principle of safety confirmation”. In view of the above, the relation of “locking up the power switch in the OFF position”, “withdrawing and possessing the key for hostage control” and “unlocking the movable guard for accessing to the working space” of the “trapped key interlock”, which is alternative to “Lockout”, should be made unate in terms of system. This paper formulates these interrelations, presents them in the form of interlock structure, and shows an example of configuration that can meet the required safety functions.
Increased night work is an important issue because of its implications on workers' health, safety and performance. This study examined the effects of brief hourly exercise as a countermeasure against the adverse effects of night work, especially for workers requiring sustained attention while working in a prolonged sitting posture. During simulated night work (22:00-08:00), participants were required to follow an hourly schedule comprising a 30-min task, 15-min test and 15-min break. The study included 2 experimental conditions: (1) hourly exercise (HE; hourly exercise for 3 min during breaks) and (2) control (without exercise during breaks). Throughout the test period, work performance in the last 10 min of each 30-min task was better under the HE condition than under the control condition (p<0.01). During the second half of the test period, exercise showed an effect on sustained attention (p=0.02). Parasympathetic nerve activity under the HE condition was less than that under the control condition (p<0.01). However, exercise was not effective in reducing subjective fatigue and sleepiness. These results suggest that brief hourly exercise acts as a restraint on parasympathetic nerve activity and is capable of sustaining attention levels during the circadian rhythm nadir that occurs during early morning.
The safety and environmental aspects of a manufacturing process are important due to increased environmental regulations and life quality. In this paper, the concentration of aerosols in the breathing zone of the operator of Electrical Discharge Machining (EDM), a commonly used non traditional manufacturing process is presented. The pattern of aerosol emissions from this process with varying process parameters such as peak current, pulse duration, dielectric flushing pressure and the level of dielectric was evaluated. Further, the HAZOP technique was employed to identify the inherent safety aspects and fire risk of the EDM process under different working conditions. The analysis of aerosol exposure showed that the concentration of aerosol was increased with increase in the peak current, pulse duration and dielectric level and was decreased with increase in the flushing pressure. It was also found that at higher values of peak current (7A) and pulse duration (520 μs), the concentration of aerosols at breathing zone of the operator was above the permissible exposure limit value for respirable particulates (5 mg/m3). HAZOP study of the EDM process showed that this process is vulnerable to fire and explosion hazards. A detailed discussion on preventing the fire and explosion hazard is presented in this paper. The emission and risk of fire of the EDM process can be minimized by selecting proper process parameters and employing appropriate control strategy.
With regard to metabolic syndrome-related risks (MS risks), obese workers have been the focus of attention, and less attention has been paid to non-obese subjects as if they were free from the risks. The present analysis was initiated to know if no-obesity means no-MS risks. Participants of the study were 804 male workers, who showed no pathological findings in 12 MS-related and other health parameters in 2003, and had complete sets of data in 2008. They were classified by BMI in 2003 into lean (<18.5), normal (≥18.5 to <25) and obese groups (≥25). Proportion of MS in 2008 was examined by use of the second phase of MS criteria. Proportions for the lean, normal and obese subjects who met MS criteria in 2008 were 3.2, 4.8 and 5.3%, respectively, with no significant difference in proportions among them. In the non-obese (i.e., lean+normal) group, age was not significantly influential to increase BMI. Thus, the MS risk exists even in non-obese young workers. Anti-MS effort should be directed not only to obese but to non-obese workers, and care should be extended irrespective of ages.
In the present study, we conducted a clinical controlled trial to evaluate the effects of cognitive behavioral therapy (CBT) training in improving depression and self-esteem in workers. A total of 261 workers were assigned to either an intervention group (n=137) or a waiting-list group (n=124). The intervention group was offered participation in a group session with CBT specialists and three e-mail sessions with occupational health care staff. Between-group differences in the change in Center for Epidemiologic Studies Depression Scale (CES-D) and Self-Esteem Scale from baseline to three months after the end of training were assessed by analysis of covariance. All subjects in the intervention group completed the group session and 114 (83%) completed the three e-mail sessions. CES-D score decreased by 2.21 points in the intervention group but increased by 0.12 points in the control group, a significant difference of -2.33 points (95% confidence interval: -3.89 to-0.77; p<0.001). The between-group difference in change of self-esteem scores was not significant. Results of the present study suggest that CBT training cooperatively provided by CBT specialists and occupational health care staff using brief e-mail is effective in improving feelings of depression in workers.
Job strain has become a major concern because of its potential impacts on worker well-being and performance. This cross-sectional study aimed to assess the prevalence of, and examine factors associated with, job strain among workers in a rubber-glove factory, in a central province of Thailand. A total of 200 workers aged 18-55 yr, who had worked at the factory for at least 6 months, completed the Job Content Questionnaire (JCQ) (Thai Version). Two of 5 scales in the JCQ were used to measure job strain, i.e.; job control and psychological job demand. The prevalence of job strain was 27.5%. Multiple logistic regression analysis indicated two variables significantly associated with job strain: low supervisor social support (adjusted OR=3.08; 95%CI: 1.38-6.91) and high job insecurity (adjusted OR=2.25; 95%CI: 1.04-4.88). Effective training for supervisors, to create good relationships among workers and supervisors, and ensuring steady and secure jobs for good employees, are necessary.
The present study investigated the effectiveness of a weight loss program during routine medical follow-up with regularity on promoting weight reduction in obese obstructive sleep apnea hypopnea syndrome (OSAHS) subjects receiving continuous positive airway pressure treatment (CPAP). A total of 10 male obese OSAHS subjects treated with CPAP were enrolled in the present study that was an intervention study without a control and had a pre-post test study design. The age was 50.7 (7.8) (mean (SD)) years, and body mass index was 30.7 (2.5) kg/m2. A 4-month weight loss program was developed, using a combined approach of diet and physical activity based on individual counseling with behavioral approach. At 4 months, weight was significantly decreased compared with the baseline value (88.4 (8.9) kg to 86.9 (8.8) kg, p=0.005), and the mean weight loss was a 1.7% decrease from the baseline. There was significantly higher percent weight loss in the group with a CPAP duration <30 months, than in the group ≥30 months (2.7 (1.6) % vs. 0.6 (0.5) %, p=0.032). The present study shows that a weight loss program may be useful in reducing weight for male obese OSAHS subjects treated with CPAP.