Evaluation of an 8 hour versus a 12 hour shift roster on employees at a power station

The Effect of Blue-enriched White Light on Cognitive Performances and Sleepiness of Simulated Shift Workers: A Randomized Controlled Trial

BACKGROUND

Shift work is associated with reduced performance and efficiency, the current study aimed at investigating whether blue-enriched white light could improve workers' performance.

METHODS

The study, which adopted a randomized controlled trial, was conducted among 48 simulated shift workers. The participants performed sustained attention task, working memory task, and sleepiness task during night shift work. The data was analyzed using two-way repeated measure ANOVA.

RESULTS

The results indicated that, compared to conventional light, participants' correct responses of the sustained attention significantly increased when they were exposed to blue-enriched white light, correspondingly, the commission errors and omission errors declined. Furthermore, the blue-enriched white light had a significant effect on the decrease of sleepiness. However, the working memory was not significantly affected.

CONCLUSION

Exposing to blue-enriched white light can improve sustained attention and reduce sleepiness.

Prevalence of Insomnia in Various Industries and Associated Demographic Factors in Night-Shift Workers Using Workers' Specific Health Examination Data

This study aimed to investigate the prevalence of insomnia in various industries and the associated demographic factors. We searched the nationwide night-shift Workers’ Specific Health Examination (nsWSHE) data extracted in 2015 information on factors associated with insomnia, including sex, age, and the number of workers in the workplace. The prevalence of moderate insomnia in the total industry was 4.6%. Industries with a high prevalence of insomnia included the arts, sports, and recreation-related services industry, followed by the activities of household as employers industry, financial and insurance activities industry, human health and social welfare industry, and accommodation and food services activities industry. The prevalence of insomnia was higher in women. Age was a significant factor. In general, insomnia was highest among those aged ≥60 years. Insomnia was highest in small-sized companies with fewer than five employees compared to large enterprises with more than 1000 employees. This study is the first to analyze the prevalence of insomnia among night-shift workers who participated in the WSHEs. The findings of this study can be used to prioritize intervention policies for insomnia among night-shift workers.

Non-Pharmacological Interventions to Improve Chronic Disease Risk Factors and Sleep in Shift Workers: A Systematic Review and Meta-Analysis

Shift work is associated with adverse chronic health outcomes. Addressing chronic disease risk factors including biomedical risk factors, behavioural risk factors, as well as sleep and perceived health status, affords an opportunity to improve health outcomes in shift workers. The present study aimed to conduct a systematic review, qualitative synthesis, and meta-analysis of non-pharmacological interventions targeting chronic disease risk factors, including sleep, in shift workers. A total of 8465 records were retrieved; 65 publications were eligible for inclusion in qualitative analysis. Random-effects meta-analysis were conducted for eight eligible health outcomes, including a total of thirty-nine studies. Interventions resulted in increased objective sleep duration (Hedges' g = 0.73; CI: 0.36, 1.10, k = 16), improved objective sleep efficiency (Hedges' g = 0.48; CI: 0.20, 0.76, k = 10) and a small increase in both subjective sleep duration (Hedges' g = 0.11; CI: -0.04, 0.27, k = 19) and sleep quality (Hedges' g = 0.11; CI: -0.11, 0.33, k = 21). Interventions also improved perceived health status (Hedges' g = 0.20; CI: -0.05, 0.46, k = 8), decreased systolic (Hedges' g = 0.26; CI: -0.54, 0.02, k = 7) and diastolic (Hedges' g = 0.06; CI: -0.23, 0.36, k = 7) blood pressure, and reduced body mass index (Hedges' g = -0.04; CI: -0.37, 0.29, k = 9). The current study suggests interventions may improve chronic disease risk factors and sleep in shift workers; however, this could only be objectively assessed for a limited number of risk factor endpoints. Future interventions could explore the impact of non-pharmacological interventions on a broader range of chronic disease risk factors to better characterise targets for improved health outcomes in shift workers.

Analyzing the effect of social interaction on job demands and health in the example of flexible shiftwork

In the literature, shiftwork-related stress is often connected with health complaints. However, it has been shown that these are not equally distributed. Further reasons must exist as to why stress resulting from shiftwork only affects health in some cases. In a study with 653 employees working in highly flexible shiftwork conditions, an examination was made of the factors affecting the relationship between job demands and health status. The results show that satisfaction with leadership influences whether unevenly distributed work and time pressure have a significant impact on health. The factor of other people living in the household significantly influences whether time pressure and emotional stress lead to health complaints. The study concluded that the impact of social interaction as a resource is not limited to the workplace. Social interaction, as a personal resource, can be helpful in both the professional and private spheres.

Prediction of Health-Related Leave Days among Workers in the Energy Sector by Means of Genetic Algorithms

In this research, a model is proposed for predicting the number of days absent from work due to sick or health-related leave among workers in the industry sector, according to ergonomic, social and work-related factors. It employs selected microdata from the Sixth European Working Conditions Survey (EWCS) and combines a genetic algorithm with Multivariate Adaptive Regression Splines (MARS). The most relevant explanatory variables identified by the model can be included in the following categories: ergonomics, psychosocial factors, working conditions and personal data and physiological characteristics. These categories are interrelated, and it is difficult to establish boundaries between them. Any managing program has to act on factors that affect the employees’ general health status, process design, workplace environment, ergonomics and psychosocial working context, among others, to achieve success. This has an extensive field of application in the energy sector.

Burnout, Sleep, and Sleepiness during Day and Night Shifts in Transition from 8- to 12-Hour Shift Rosters among Airline Ground Crew Managers

Organizational changes in shift scheduling provide rare opportunities for field studies aimed at investigating the effects of such changes on health and wellbeing. We studied the effects of a transition from 8-hour (8-h) to 12-hour (12-h) shift rosters in 39 airline ground crew managers on burnout, sleep quality, and sleepiness. Assessments were collected during the 8-h and were repeated three months after the transition to 12-h shift rosters. These assessments included the Shirom-Melamed Burnout Measure (SMBM), the Pittsburgh Sleep Quality Index (PSQI), actigraphy, the Karolinska Sleepiness Scale (KSS) completed hourly during one day and two night shifts, and caffeine intake. Findings demonstrated lower burnout, improved sleep quality, improved quality of naps, and increased afternoon sleepiness during the 12-h day shift. Napping was reported during 12-h night shifts by 36% of the sample. In nappers, increased night shift sleepiness was associated with increased caffeine intake on 8- and 12-h shifts. In non-nappers, increased night shift sleepiness was associated with decreased caffeine intake on the 8-h shift only. Change in shift length affects other structural and behavioral parameters in the workplace, making it challenging to isolate distinct characteristics of the two rosters and their relative effects on study outcomes. Individual differences in adaptation to shiftwork may also play a role.

Evaluation of the effect of shift work on serum cholesterol and triglyceride levels

Background:

Working outside daylight hours (7 am to 7 pm) is called shift work. Shift work is a common practice in many industries and factories such as steel industries, petroleum industries, power plants, and in some services such as medicine and nursing and police forces, in which professionals provide services during day and night.

Objectives:

Considering the contradictory reports of different studies, we decided to evaluate the effect of shift work on cholesterol and triglyceride (TG) levels through a historical cohort on steel industry workers.

Patients and Methods:

This retrospective cohort study was performed on all the staff of Isfahan’s Mobarakeh Steel Company between years 2002 and 2011. There were 5773 participants in this study. Data were collected from the medical records of the staff using the census method. For analysis of data, generalized estimating equation (GEE) regression was used.

Results:

The results showed a significant difference in cholesterol levels between shift workers and day workers on the first observation (P < 0.001), yet no such difference was observed for TG (P = 0.853). Moreover, the results showed that the variables of age, work experience and BMI were not similar between shift workers and day workers. Therefore, to remove the effect of such variables, we used GEE regression. Despite the borderline difference of cholesterol between regular shift workers and day workers, this correlation was not statistically significant (P = 0.051). The results for TG also showed no correlation with shift work.

Conclusions:

According to the findings of this study, there is no relationship between shift work and changes in serum TG and cholesterol. The lack of relationship can be due to shift plans for shift workers, nutrition, or the “Healthy Heart project” at Isfahan Mobarakeh Steel Company.

Sleep deprivation due to shift work

Sleep deprivation due to shift work is related to perturbation of the sleep/wake cycle, associated with the modified activity/rest pattern. This may cause a significant disruption of circadian rhythms of biologic functions, driven by the body clock located in the suprachiasmatic nuclei of the hypothalamus. Shift and night workers have to change sleep times and strategies according to their duty periods; consequently, both sleep length and quality can be considerably affected depending on the variable start and finish times on different shifts. About 10% of night and rotating shift workers, aged between 18 and 65 years, have been estimated to have a diagnosable "shift-work sleep disorder," according to the International Classification of Sleep Disorders, version 2 (ICSD-2). In the long run, this may lead to persistent and severe disturbances of sleep, chronic fatigue and psychoneurotic syndromes, besides being a risk or aggravating factor for accidents, gastrointestinal, cardiovascular, and reproductive disorders, as well as, probably, for cancer. Preventive and corrective actions deal with the organization of shift schedules according to ergonomic criteria, careful health surveillance, appropriate education and training on effective countermeasures, in particular, sleep hygiene and napping.

The impact of various work schedules on sleep complaints and minor accidents during work or leisure time: evidence from a national survey

OBJECTIVE

To explore the prevalence of insomnia symptoms and excessive daytime sleepiness (EDS) in different work schedules and the impact of shift schedules on the risk of minor accidents during work or leisure time.

METHODS

Using the data from Taiwan Social Development Trend Survey in 2005 (n = 18,794), insomnia symptoms, EDS, and minor accidents were analyzed using descriptive statistics and multivariable logistic regression model.

RESULTS

The evening-to-night group had significantly higher prevalence rates of insomnia symptoms. Higher prevalence rate of EDS was presented in both day-to-evening and evening-to-night groups. Adjusting for confounders, the day-to-evening shift had a higher odds ratio of minor accidents as compared with the fixed daytime workers.

CONCLUSIONS

Extended-shift workers tend to experience insomnia symptoms and EDS and have an increased likelihood of minor accidents.

The effects of a self-selected nap opportunity on the psychophysiological, performance and subjective measures during a simulated industrial night shift regimen

This study compared the effects of a 1 h self-selected recovery period to those of a standard night shift arrangement (with a total break time of 1-h) over a simulated three-day night shift schedule in a laboratory setting. Results showed that the inclusion of the flexible nap scheme resulted in higher performance output, improvements in physiological strain responses and reduced sleepiness during each night shift and generally over the three-night cycle. Certain variables also revealed the impact of napping compared with the standard rest break condition on the circadian rhythm. The sleep diary records show that the inclusion of the current intervention did not significantly reduce daytime recovery sleep. The results suggest that the potential benefits of flexible napping may outweigh the logistical effort it requires in a workplace environment.

PRACTITIONER SUMMARY

Consensus on appropriate napping strategies for shift work remains a challenge. This simulated night shift laboratory study sought to determine the effects of a 1-h self-selected nap opportunity relative to a normal shift set-up. The nap improved performance and decreased sleepiness, without affecting daytime sleep.

Conflict Between Work and Family Roles and Satisfaction among Nurses in Different Shift Systems in Croatia: a Questionnaire Survey

The objective of this study was to examine the perception of conflict between work and family roles and job, family, and life satisfaction among nurses in Croatia. One hundred and twenty-nine nurses (married mothers) working in hospitals in Zadar, Šibenik, and Split were divided in four groups according to their worktime schedule. The participants completed a survey, which included a set of sociodemographic-type questions, questions about the level and allocation of family responsibilities between spouses, and scales measuring the perceived negative effects of worktime, psychological demands of the work, work-family conflict, and semantic differential scales for measuring the affective and cognitive-evaluative component of job, family, and life satisfaction. This was the first study in Croatia to deal with work-family conflict among nurses or workers with different shift systems.

The results of this study indicate that nurses working morning shifts only experienced less conflict between work and family than other groups of nurses, who worked the morning, afternoon, and the night shift. The cognitive-evaluative component of job satisfaction was the highest among morning shift nurses and the lowest in nurses who worked 12-hour shifts, while the affective component of life satisfaction was the lowest in nurses working irregular and backward rotated shifts. These results confirm that shiftwork makes the work-family role conflict even worse. They also support the view that the type of shift rotation matters.

12-h or 8-h shifts? It depends

Since 12-h shifts were first implemented, the question has been asked - are 'twelves' better than 'eights'? People trying to answer this question invariably refer to the limited literature at their disposal, often piecemeal, small-scale studies comparing 8-h versus 12-h shifts in isolated groups of workers in which many other factors vary concurrently. The narrow perspective and sometimes 'vested interests' of the organizations, researchers, publishers and individual workers can influence both the choice of measures, the analysis of results and their interpretation. The current review suggests that it is not sufficient to evaluate a shift pattern on the basis of a single dimension of a working time arrangement, such as shift length. Numerous factors associated with the work practice influence the outcome of a shift pattern including start times, pattern of shifts and amount of overtime. Moreover, the type of work being done and the demographics or characteristics of the workforce are additional mediating factors. Finally, and perhaps most critically, the relative importance assigned to different outcome measures is an important consideration. There are situations where total sleep time might increase following a change to 12-h shifts, whereas domestic life for some workers may deteriorate. Additionally, safety measures may show improvements on 8-h shifts but physical or psychological health outcomes may be worse. The myriad combinations of work pattern, work task, worker and outcome measure under investigation mean that the best way to take account of these complexities may be to use an approach that manages 'system' risk. Given the non-linearities in the system, and the fact that current approaches either ignore, or privilege a subset of outcomes, it is perhaps more appropriate to conceptualize working time arrangements as an 'ecosystem' and to address the risks in the overall system as opposed to a single dimension such as shift length.

Shiftwork Problems

U radu se raspravlja o negativnim utjecajima smjenskog rada koji su klasificirani u četiri kategorije učinaka: na biološke funkcije, radnu efikasnost, društvene / obiteljske aspekte života te na zdravlje. Dan je sustavni pregled dosadašnjih istraživanja zdravstvenih problema smjenskih radnika u čijoj je osnovi narušavanje cirkadijurnih ritmova organizma koju nameće smjenski / noćni rad. Zdravstveni problemi koji se dovode u vezu sa smjenskim radom su ovi: problemi sa spavanjem, gastrointestinalne i kardiovaskularne bolesti, karcinom, problemi s reproduktivnim funkcijama žena te lošije psihičko zdravlje.

U radu se također raspravlja o toleranciji smjenskog rada. Pri tome je kao teoretski okvir povezanosti smjenskog rada i negativnih zdravstvenih posljedica rabljen procesni model koji su postavili Smith i suradnici 1999. Poseban naglasak stavljen je na individualne i organizacijske faktore o kojima ovisi mogućnost prilagodbe na smjenski rad te tolerancija takvog rada. Značajni prediktori tolerancije smjenskog rada su: dob, spol, jutarnjost-večernjost, rigidnost-fleksibilnost u navikama spavanja, obiteljska situacija, higijena spavanja te zdrava prehrana. S obzirom na rezultate istraživanja koji upućuju na povezanost nekih karakteristika organizacije smjenskog rada s tolerancijom prema smjenskom radu, kao što su: broj radnih smjena i trajanje smjene, broj sukcesivnih noćnih smjena, regularnost smjena, brzina i smjer rotacije smjena, preporučene su intervencijske strategije u organizaciji smjenskog rada.

The effects of different roster schedules on sleep in miners

Shiftwork involving early morning starts and night work can affect both sleep and fatigue. This study aimed to assess the impact of different rostering schedules at an Australian mine site on sleep and subjective sleep quality. Participants worked one of four rosters; 4 x 4 (n = 14) 4D4O4N4O 7 x 4 (n = 10) 7D4O7N40 10 x 5 (n = 17) 5D5N50 14 x 7 (n = 12) 7D7N70. Sleep (wrist actigraphy and sleep diaries) was monitored for a full roster cycle including days off. Total sleep time (TST) was longer on days off (7.0 +/- 1.9) compared to sleep when on day (6.0 +/- 1.0) and nightshifts (6.2 +/- 1.6). Despite an increase in TST on days off, this may be insufficient to recover from the severe sleep restriction occurring during work times. Restricted sleep and quick shift-change periods may lead to long-term sleep loss and associated fatigue.

Differences in medical error risk among nurses working two- and three-shift systems at teaching hospitals: a six-month prospective study

Shift work, including night work, has been regarded as a risk factor for medical safety. However, few studies have investigated the difference in medical error risk between two- and three-shift systems. A total of 1,506 registered nurses working shifts at teaching hospitals participated in this study to evaluate the difference in medical error risk between two- and three-shift systems. After adjustment for potential confounding factors using a log Poisson generalized estimating equation model, the results showed significantly higher frequencies of perceived adverse events over 6 months in the three-shift than in the two-shift system, with estimated mean numbers of adverse events of 1.05 and 0.74, respectively. Shorter intervals after night shifts and greater frequency of night shifts in three-shift systems, which reduce the recovery time from night shift work, may be linked to increased medical errors by nurses.

Effects of Extended Work Shifts and Shift Work on Patient Safety, Productivity, and Employee Health

It is estimated 1.3 million health care errors occur each year and of those errors 48,000 to 98,000 result in the deaths of patients (Barger et al., 2006). Errors occur for a variety of reasons, including the effects of extended work hours and shift work. The need for around-the-clock staff coverage has resulted in creative ways to maintain quality patient care, keep health care errors or adverse events to a minimum, and still meet the needs of the organization. One way organizations have attempted to alleviate staff shortages is to create extended work shifts. Instead of the standard 8-hour shift, workers are now working 10, 12, 16, or more hours to provide continuous patient care. Although literature does support these staffing patterns, it cannot be denied that shifts beyond the traditional 8 hours increase staff fatigue, health care errors, and adverse events and outcomes and decrease alertness and productivity. This article includes a review of current literature on shift work, the definition of shift work, error rates and adverse outcomes related to shift work, health effects on shift workers, shift work effects on older workers, recommended optimal shift length, positive and negative effects of shift work on the shift worker, hazards associated with driving after extended shifts, and implications for occupational health nurses.

Changes in physical performance among construction workers during extended workweeks with 12-hour workdays

PURPOSE

To investigate changes of physical performance during long working hours and extended workweeks among construction workers with temporary accommodation in camps.

METHODS

Nineteen construction workers with 12-h workdays and extended workweeks participated. Physical performance in the morning and evening of the second and eleventh workdays was tested by endurance, ability to react to a sudden load, flexibility of the back, handgrip strength and sub-maximal HR during a bicycle test. HR was registered throughout two separate workdays.

RESULTS

HR during each of the two separate workdays corresponded to a relative workload of 25%. Sub-maximal HR was lower, reaction time faster and handgrip strength higher in the end of each test day. In the end of the work period, sub-maximal HR was lower, reaction time faster and sitting balance was better.

CONCLUSION

No trends of decreased physical performance were found after a workday or a work period.

Rail signallers' assessments of their satisfaction with different shift work systems

This paper describes rail employee views on shift-work systems obtained from administration of the Rail Ergonomics Questionnaire (REQUEST) to a large sample of rail professionals in Great Britain, achieving a response rate of 83%. Results from signallers, the largest occupational grouping in the survey (n = 3230), are presented. ANOVA has been used to investigate the effects of different aspects of the shift patterns (the length of shift and the speed and direction of rotation of shifts) and the effects of age on the ratings of satisfaction with the shift system. The findings from the analyses indicate preferences for the 12-h shift system over the 7-9-h rotating shift system. There were no main effects of the direction of rotation of shifts, though there were significant interactions between the direction of rotation of shifts, the numbers of consecutive shifts and the age of respondents. There is a need for clear data addressing the impact on workers of key shift-related parameters such as shift length, direction of rotation of shifts, numbers of consecutive shifts and personal factors such as age. This paper presents findings of the effects of these key shift and personal parameters and their interactions on respondents' ratings of satisfaction with the shift system, using data collected with REQUEST in a national survey of rail signallers.

[Shiftwork and quality of life among critical care nurses and paramedical personnel]

BACKGROUND

The need to reorganize hospital care in view of the inadequate number of staff available has led some departments to change shift hours to two 12-hour shifts daily. The impact of this organization on the quality of life (QoL) and daily life of caregivers has not been studied sufficiently.

OBJECTIVE

The objective of our study was to document the role of the type of schedule worked on QoL, fatigue, and burnout among critical care nursing and paramedical staff.

METHODS

A descriptive survey was conducted among the nurses, nurses' aides, and other paramedical staff of 3 critical care departments at the Timone Hospital Center in Marseille. Three groups were defined by the type of hours worked: 12-hour alternating night and day shifts, 10-hour nights, and 8-hour days. A booklet of questions was distributed to all staff; it contained one section that collected social, demographic, family and occupational data and another containing self-administered standardized and validated questionnaires that assessed QoL (SF36), fatigue (MFIS-5), and burnout (MBI).

RESULTS

The participation rate was 78%. The univariate analysis showed QoL was best in the group working 12-hour shifts, compared with the other 2 groups, while their levels of fatigue and burnout were similar. The multivariate approach, which sought to document the specific role of length of work shift on QoL showed that while the physical component of QoL might be influenced by number of hours worked (staff working 10-hour nights had lower QoL scores than either of the others), but the psychological component was not; only gender and duration of commute were significantly associated with QoL.

CONCLUSION

These results add yet more divergence to the already existing reports on how employees experience the length of their workday. The specific scheduling does not appear to affect either fatigue or the mental component of QoL, but does appear to affect the physical component of QoL. Other studies are necessary to validate these initial approaches.

Tolerance of shift work

This study aimed to explore criteria for shift work tolerance and to investigate the relationships between personality traits and states and shift work tolerance. Eighty-nine policemen and police women completed a questionnaire, once during consecutive night shifts and again during rotating shifts, and their responses were used to assess anxiety, emotional control, positive and negative affect, health complaints, sleep quality, difficulties in social and domestic life, and perceptions about shift work. Both the criteria for tolerance and the relationship between tolerance and personality varied according to shift type. Night shift tolerance involved four factors--somatic health, flexibility, sleep and sleep need--while rotating shift tolerance involved three factors--somatic health, flexibility and fatigue. Tolerance of shift work was associated with anxiety, repressive emotional style and mood. During night shifts, anxiety was the most influential personality factor for the somatic health and sleep dimensions of shift tolerance. During rotating shifts, positive and negative moods, rather than trait personality factors, were important predictors of the somatic health and fatigue shift tolerance dimensions. These results suggest a mechanism for more effective matching of workers to suitable shift schedules.

A systematic review of the neurobehavioural and physiological effects of shiftwork systems

Shiftwork is a common experience for many workers. There are a wide range of shift systems in use, with a number of general approaches and myriad variations of each one. Many aspects of shift systems have been studied, but attempts to reach definitive conclusions about appropriate designs have been hampered by a number of methodological issues. The aim of this systematic review was to provide evidence-based recommendations on the effect of various shift systems on neurobehavioural and physiological functioning and to identify areas which are lacking in appropriate evidence. Two main aspects of shift design were able to be considered-the direction of shift rotation and extended shift length (mainly 12-h shifts). Other areas for which there was at least one relevant paper of adequate methodology were the use of naps during night shifts, the starting time of shifts, and several other specific shift issues. Overall, the review found there is insufficient evidence to support definitive conclusions regarding any of these factors. However, the analysis provides support for the use of forward rotating shift systems in preference to backward rotating shift systems, at last as far as 8-h shifts are concerned. There are many unanswered questions in shift design. For these questions to be answered, it is important that the methodological shortcomings present in most of the studies published to date be overcome.

Long working hours, safety, and health: toward a National Research Agenda

BACKGROUND

A significant and growing number of people work long hours. Research examining impacts is limited, but raises concerns about risks to the worker, the family, the employer, and the community. The purpose of this report, which is authored by the National Occupational Research Agenda (NORA) Long Work Hours Team, is to motivate and guide future research by proposing a framework for studying long work hours and discussing research gaps.

METHODS

The NORA Long Work Hours Team examined research reports and literature reviews, and gathered input from a conference on long work hours organized by the Team and faculty from University of Maryland.

RESULTS AND CONCLUSION

A framework is proposed for long work hours, including determinants, outcomes, and moderating factors of long work hours, suggesting that studies need to include more clear and complete descriptions of work schedules, worker characteristics, and the work environment, and need to consider a wider range of possible health, safety, social and economic outcomes for workers, families, employers, and the community. Additional studies are needed on vulnerable employee groups and those critical to public safety. More studies are also needed to develop interventions and test their effectiveness.

Possible broad impacts of long work hours

The paper summarizes research linking long work hours to a wide range of risks to workers, families, employers, and the community. The risks are theorized to stem from less time to recover from work, longer exposure to workplace hazards, and less time to attend to non-work responsibilities. Risks to workers include sleep deprivation, poor recovery from work, decrements in neuro-cognitive and physiological functioning, illnesses, adverse reproductive outcomes, and injuries. Risks to families include delayed marriages and child bearing, and obesity in children. Risks to employers include reduced productivity and increases in workers errors. Mistakes by fatigued workers have broad reaching impacts to the community: medical errors, automobile crashes with other drivers on the road, and industrial disasters that damage the environment.

The effect of sleepiness on performance monitoring: I know what I am doing, but do I care?

The behavioral, cognitive, and psychophysiological effects of extended wakefulness are well known. As time awake increases, errors become more common and are often attributed to lapses in attention. Such lapses can be reflected in the error-related negativity (Ne/ERN), a negative electroencephalogram deflection occurring after errors and is thought to be related to error detection or response conflict. Following the Ne/ERN, a positive deflection (error positivity, Pe) is also observed and is thought to reflect further evaluation of the error. To elicit Ne/ERNs, the Eriksen Flanker Task was administered to 17 women (aged 19-45 years) at two levels of alertness (4 and 20 h awake). After extended wakefulness, participants reported being subjectively sleepier and performing worse, but showed no significant difference in subjective effort. Across alertness conditions, they reported a similar number of subjective errors which closely matched an objective analysis of the errors. The Ne/ERN was not significantly reduced by sleepiness in contrast to the Pe which was reduced. Behavioral slowing after errors was larger in the alert than in the sleepy condition. These results show that after 20 h of wakefulness, individuals are reacting to their errors. However, further evaluation of the error, and remediation of these errors may be impaired despite continued effort.

The impact of roster changes on absenteeism and incident frequency in an Australian coal mine

BACKGROUND

The occupational health and safety implications associated with compressed and extended work periods have not been fully explored in the mining sector.

AIMS

To examine the impact on employee health and safety of changes to the roster system in an Australian coal mine.

METHODS

Absenteeism and incident frequency rate data were collected over a 33 month period that covered three different roster schedules. Period 1 covered the original 8-hour/7-day roster. Period 2 covered a 12-month period under a 12-hour/7-day schedule, and period 3 covered a 12-month period during which a roster that scheduled shifts only on weekdays, with uncapped overtime on weekends and days off (12-hour/5-day) was in place. Data were collected and analysed from the maintenance, mining, and coal preparation plant (CPP) sectors.

RESULTS

The only significant change in absenteeism rates was an increase in the maintenance sector in the third data collection period. Absenteeism rates in the mining and CPP sectors were not different between data collection periods. The increase in the maintenance sector may be owing to: (1) a greater requirement for maintenance employees to perform overtime as a result of the roster change compared to other employee groups; or (2) greater monotony associated with extended work periods for maintenance employees compared to others. After the first roster change, accident incident frequency decreased in the CPP sector but not in the other sectors. There was no effect on incident frequency after the second roster change in any sector.

CONCLUSIONS

The current study did not find significant negative effects of a 12-hour pattern, when compared to an 8-hour system. However, when unregulated and excessive overtime was introduced as part of the 12-hour/5-day roster, absenteeism rates were increased in the maintenance sector. The combination of excessive work hours and lack of consultation with employees regarding the second change may have contributed to the overall negative effects.

Staff rostering in the operating department

The smooth running of the operating department is often facilitated by the goodwill of the staff who agree to stay behind when cases overrun, or work through lunch and coffee breaks. Many perioperative staff also cover on-calls and stand-bys, causing disruption to their social and family lives. These demands may make working in the operating department harder for some staff. With reference to current shortages of perioperative staff and staff retention, Judith Tanner and Gloria Bailey discuss some suggestions for being flexible with the off duty rota which may give staff more control and more choices over when they work.