Shiftwork effects in nuclear power workers: A field study using portable computers

Abstract

This field study of nuclear power shiftworkers reports the use of hand-held computers to record alertness levels, cognitive task performance and workload ratings. Subjective ratings and performance tasks (Search and Memory-5 (SAM-5); Choice Reaction Time (CRT) were completed on the computers at 2-h intervals during selected shifts in the work schedule by maintenance crews and reactor operators. Sleep duration and quality data were also obtained during the 35-day shift cycle. Workload remained relatively stable across shifts. The night-shift was associated with shorter sleep durations and poorer sleep quality. Significantly lower levels of alertness and poorer perforniance for components of the performance tasks were also observed on the night-shift. Tinic-on-shift effects on alertness were evident, where by for the night-shift, especially, alertness dropped dramatically during the early hours. Components of SAM-5 performance showed differential time-on-shift patterning relative to each shift whereas CRT was unresponsive to time-on-shift effects. Significant variations were observed in alertness and performance components during the 12-h night-shift. Perhaps paradoxically, performance on the 12-h night-shift appeared to improve rather than deteriorate during the early-hour period that was associated with the greatest drop in alertness. This was suggestive of extra effort expenditure during this critical period.     

The impact of shiftwork on personnel at a nuclear power plant: An exploratory survey study

Shiftwork may constitute an additional risk factor in high-hazard industries where system failure could exact heavy human, environmental and economic costs. This exploratory survey study examined the impact of shiftwork upon nuclear power plant workers' perceived health, sleep, and social problem, as well as levels of alertness. Overall, the night shik proved to be the most problematic in ternis of decreases in alertness, sleep duration and quality, and disruptions to health, social and family life. The permanent shift preferences of the shiftworkers were also explored to establish the practicability of introducing a theoretically safer permanent mght shdt at such a facility. Importantly, the small proportion of the sample who showed a preference for a pemianent night shift was insufficient to provide operational cover. Although these shtftworkers reported experiencing less disruption on the night shift than those who would choose to work a permanent day shift, their preference appeared to be based upon a greater esprit de corps on this shift rather than on any predisposing individual characteristics. These results have practical implications for work scheduling in high-hazard industries.

The present study investigates the dimensional structure of the psychosocial work environment as assessed by Karasek's job characteristics scales and a set of factorial scales derived from the Dictionary of Occupational Titles (DOT) observers' ratings of occupational characteristics for census occupations. Scale scores on the Karasek and DOT were linked to information on occupation from the Epidemiologc Catchment Area (ECA) study sample. Scale intercorreladons and factor analysis were performed on those ECA subjects who reported ever having a full-time job (n=11,789). DOT'sS Substantive Complexity scale was positively correlated with Karasek's Skill Discretion and Decision Authority scales, and DOT's Physical Demands and Hazards scale was positively correlated with Karasek's Physical Demands scale. In addition, the DOT system compared to the Karasek system seems to assess psychosocial work domains less characteristic of traditional industrial jobs (interpersonal stress, expressive work). The content validity of the Karasek scales might be increased with the assessment of these domains. Giving support to Karasek's Demand/Control Model, the factor structure of the psychosocial work enviromnent in the probability sample of five US metropolitan populations yielded two major dimensions: Control, and Physical Demands.     

Performance, alertness, and sleep after 3·5 years of 12 h shifts: A follow-up study

Control room operators at a continuous processing plant have been working a 12 h/3-4 day rotating shift schedule for over 3 years. After 7 months on this schedule, our initial assessment indicated decrements in performance and alertness, and a mild to moderate sleep debt, when the 12 h shift schedule was compared to the previously-worked 8 h shift schedule. In an effort to track long-term adaptation to the schedule, we conducted a 3 & 5 year follow-up evaluation using the same set of measures. Long-term follow-up testing revealed persistent decrements in performance and alertness attributable to 12 h shifts, and 1-3 h reductions in total sleep time after 12 h night shifts. Little deterioration in performance or alertness was observed across the workweek, which suggested day-to-day recovery from the extended workshift. The popularity of the 12 h shift schedule at this worksite indicates that the workers are willing to tolerate extra fatigue to derive other benefits from this schedule.     

Characterizing performance in socio-technical systems: A modeling framework in the domain of nuclear power

In modeling complex socio-technical systems, the critical nature of many interactions between human and automation are often unrecognized until the system experiences catastrophic consequences. One reason for this is that the systems are generally very robust and serious problems are rare. Another reason is the difficulty in modeling the variety of interactions in a manner compatible with analytical and/or computational models of the technological components of the system. Organizational issues and extraneous influences add to these modeling difficulties. We have developed a modeling framework that integrates certain ideas from social networks, graph theory, and simulation, all tied together using heuristics that reflect deep domain knowledge. This framework forms the basis for a computational implementation, portions of which have been implemented. Details of the model and the rationale for the model structure are described in this paper.     

CEO self-discipline in power use: A key moderator for the effect of CEO power

The effect of CEO power depends ultimately on how it is used (i.e., a CEO’s approach to power use), which may vary from one CEO to another. Notwithstanding extensive research on the effect of CEO power on organizational outcomes, researchers have thus far paid very limited attention to how the effect depends on individual differences. In this study I propose a new construct of CEO self-discipline in power use—defined as a CEO’s appeared conformance to the prescribed leadership norms (in particular, norms regarding how leaders should use their power)—and examine how it moderates the effect of CEO power. With a longitudinal dataset from the U.S. computer hardware and software industries, I found that CEO self-discipline in power use weakened the positive effect of CEO power on performance extremeness and improved the effect of CEO power on firm performance.     

The inverted-U relationship between stress and performance: A field study

To investigate the shape of the relationship between stress resulting from excessive demand and performance, 306 officer cadets in the Israel Defence Forces completed stress questionnaires during their training. Stress was consistently negatively related to various measures of performance. The prediction derived from the inverted-U hypothesis, that those whose ability exceeded demand and those who felt that demands taxed their ability would perform worse than those whose ability matched their demands, was not supported. Until all the requisite conditions for testing the inverted-U hypothesis are met, the authors propose relegating it to the laboratory.     

A 14-h night-shift in the control room of a fire brigade

All 29 operators in the control room of a fire brigade performed test sessions during work and leisure time at 2-h intervals on a day with a 14-h night-shift, a day off and a day with a 10-h morning shift. The test sessions consisted of a visual search choice reaction time test and two Sternberg memory search tests (1 or 5 letters had to be memorized). Furthermore, the operators recorded their oral temperature and their subjective alertness before each test session. The subject also kept a diary of work and sleep times for 14 days. The circadian rhythm of body temperature was hardly changed by a single night-shift. Parallel to the body temperature, the subjective alertness fell significantly during the night-shift reaching a minimum value at 06:00 h. The mean reaction times increased non-significantly at the end of the night-shift and the results of the two Sternberg memory search tests showed no significant trends. The sleep of the operators after the night-shift was on average reduced to 5 hs 34 min. The results of subjective rating of alertness and reaction time test are interpreted as effects of the combined influences of circadian rhythmicity, sleep loss and time on professional task. Most results support the conclusion that a 14-h night-shift without extensive breaks is not acceptable.     

A 14-h night-shift in the control room of a fire brigade

Abstract

All 29 operators in the control room of a fire brigade performed test sessions during work and leisure time at 2-h intervals on a day with a 14-h night-shift, a day off and a day with a 10-h morning shift. The test sessions consisted of a visual search choice reaction time test and two Sternberg memory search tests (1 or 5 letters had to be memorized). Furthermore, the operators recorded their oral temperature and their subjective alertness before each test session. The subject also kept a diary of work and sleep times for 14 days. The circadian rhythm of body temperature was hardly changed by a single night-shift. Parallel to the body temperature, the subjective alertness fell significantly during the night-shift reaching a minimum value at 06:00 h. The mean reaction times increased non-significantly at the end of the night-shift and the results of the two Sternberg memory search tests showed no significant trends. The sleep of the operators after the night-shift was on average reduced to 5 hs 34 min. The results of subjective rating of alertness and reaction time test are interpreted as effects of the combined influences of circadian rhythmicity, sleep loss and time on professional task. Most results support the conclusion that a 14-h night-shift without extensive breaks is not acceptable.     

Effects of various types of change in shift schedules: A controlled longitudinal study

Abstract

Data from a longitudinal study accompanying changes in shift rotas connected with a shortening of working time in the chemical industry are presented. Altogether 260 subjects forming five experimental groups participated in both the pretest and the posttest. The effects of the change in shift schedules were controlled by the inclusion of five groups in which 139 subjects participated in both tests. Five types of change in shift schedule were investigated. The purpose was to determine to what extent similar, but in some aspects differing, types of change in shift schedule varied from one another in their effects on those involved, and on which factors their attitudes towards the new shift systems depended with regard to various types of schedule change. The effects of a change in shift schedule were tested by means of the 4-group investigation design developed by Solomon (1949). The results confirm that differences in the effects of new shift systems depend on the type of change. Only in three experimental groups were improvements in health and social life observed. One experimental group showed significant signs of deterioration in subjective health. In the analyses of the factors influencing the attitude of the shiftworkers towards the new shift system, differences in the structure of the influencing factors between the experimental groups were observed. The causal analysis was used in order to test how important the factors found in each group were and which of them were dominant. It showed that the most influential factors dominated so much that the disturbances in the less influential ones lost their importance. In spite of the number of indicators analysed regarding their influence on attitude in this study, further important factors seem to exist that have not been analysed here.     

Effects of various types of change in shift schedules: A controlled longitudinal study

Data from a longitudinal study accompanying changes in shift rotas connected with a shortening of working time in the chemical industry are presented. Altogether 260 subjects forming five experimental groups participated in both the pretest and the posttest. The effects of the change in shift schedules were controlled by the inclusion of five groups in which 139 subjects participated in both tests. Five types of change in shift schedule were investigated. The purpose was to determine to what extent similar, but in some aspects differing, types of change in shift schedule varied from one another in their effects on those involved, and on which factors their attitudes towards the new shift systems depended with regard to various types of schedule change. The effects of a change in shift schedule were tested by means of the 4-group investigation design developed by Solomon (1949). The results confirm that differences in the effects of new shift systems depend on the type of change. Only in three experimental groups were improvements in health and social life observed. One experimental group showed significant signs of deterioration in subjective health. In the analyses of the factors influencing the attitude of the shiftworkers towards the new shift system, differences in the structure of the influencing factors between the experimental groups were observed. The causal analysis was used in order to test how important the factors found in each group were and which of them were dominant. It showed that the most influential factors dominated so much that the disturbances in the less influential ones lost their importance. In spite of the number of indicators analysed regarding their influence on attitude in this study, further important factors seem to exist that have not been analysed here.     

Performance management in hybrid organisations: A study in social housing

The nature and role of social housing across the European States is growing more diverse every decade. From the wide range of social housing as a percentage of total housing stock, the many different housing options provided, to the vast array of housing allocation mechanisms and differing levels of equity delivered by such mechanisms, social housing across Europe presents an increasingly complex social challenge. As such a one-size-fits-all solution to these challenges is unlikely to present itself, and researchers are therefore forced to focus on the specifics of a region or state—this is the case with this study.Within the UK, Housing Associations (HAs) have played a fundamental role within successive government social housing policies for at least three decades. However, through a succession of legislative changes, welfare reform and the deregulation of their non-profit social role, HAs have been fundamentally challenged, and are now exposed to competition from private registered providers.This study poses the overarching research question; what role does performance management play in the transition to a competitive hybridised social housing sector? Exploring this question, the paper analyses the effect of this transition through institutional isomorphism and considers specifically how a sample of English HAs sense uncertainty within the social housing sector and respond to the coercive, normative, and mimetic isomorphic pressures at play.This study finds the primary mechanism by which HAs appear to sense and respond to external changes within the sector is through their strategic performance measurement systems and metrics. Social, political, and competitive changes in the sector are ‘sensed’ as a misalignment within the existing strategic performance metrics, exerting isomorphic pressures on the organisational governance team to respond by realigning the performance metrics with the sensed changes. In this way, we posit that strategic performance measurement is linked to and plays a much more pivotal role, in the hybridisation of third-sector organisations than previously reported within the literature.Examples of such realignment include the increased use of benchmarking performance as a normative practice, and the replication of perceived best practice from the private sector to remain competitive and sustainable. Such changes reflect on an increasingly hybridised position for HAs, which now focus on improving business-critical activities, rather than simply producing performance data as a means of demonstrating good governance and compliance to their regulatory body.     

Negotiating control and achieving performance in international joint ventures: A conceptual model

Adapting well-established organization theories to international joint ventures (IJVs), this paper develops an overarching theoretical model of the determinants and effects of parent control of IJVs from an interpartner bargaining power perspective. Drawing upon power dependence, transaction costs, and agency theories, we argue that the relative bargaining power between IJV partners serves as the key determinant of control structure, and that control exerts a direct effect on the venture's performance. In addition, government influence and interpartner working relationship are critical factors that complicate the linkage between control and performance but may help to explain past conflicting results. Propositions regarding these relationships are formed for future empirical test, and implications and directions for future research are provided.     

Management performance: An empirical study of the manufacturing companies in Taiwan

This paper proposes a methodology to measure the management performance of the firms of an industry. The idea is to break down the very complicated concept of management into subjects such that the performance of each subject can be measured. The performances of all subjects are then aggregated to form an overall performance of management. The weights associated with the subjects which play a decisive role in aggregation are determined from a two-stage method. This method takes into account both the experience of the experts and the reality reflected by the data collected from the firms. Therefore, the weights generated are more acceptable to the firms. An example of the manufacturing firms in Taiwan illustrates how management is broken down into subjects and how their performances are aggregated. A regression analysis shows that management, in addition to capital and labor, makes a significant contribution to organizational performance. Although the discussion of this paper is confined to the manufacturing industry in Taiwan, the methodology can be applied to other industries and other countries.     

Perceived Nuclear Risk, Organizational Commitment, and Appraisals of Management: A Study of Nuclear Power Plant Personnel

This study examined to what extent nuclear risk perceptions, organizational commitment (OC), and appraisals of management are associated with each other among nuclear power plant personnel. The sample consisted of 428 nuclear power plant workers who completed a questionnaire at their workplace. Perceived nuclear risk and OC were most closely related to the appraisals of the top management of the organization. As the trust in and satisfaction with the top management increased, perceived nuclear safety and acceptance of the organizational goals and values heightened. This result is discussed in the context of industrial safety management.     

The impact of social power and influence on the implementation of innovation strategies: A case study of a UK mega infrastructure construction project

Influence plays a key role in reaching consensus among multiple actors involved in project-based decision-making processes. While prior literature devotes considerable attention to describing influence, little attention has been paid to influence at the individual level of the strategic project manager within the context of megaprojects. This research intended to fill this knowledge gap by identifying and describing the influence strategies that a strategic project manager applies when implementing innovation strategies on megaprojects. A qualitative case study was used to examine the complex social processes involved in a major UK capital investment programme. The findings underline a critical subset of influence strategies, notably higher-management support, inspirational appeal and bargaining. The study proposes a utilitarian structure of social power comprising selective, supportive and executory power bases.     

A feminist poststructuralist analysis of HRD: why bodies,power and reflexivity matter

A burgeoning amount of scholarship has attempted to unravel critical approaches to investigating human resource development (HRD). There are limited critiques, however, of gender, diversity and the intersections of these deliberations within HRD theorizing. Adopting a feminist poststructuralist approach, this paper advances critical understandings of HRD by challenging epistemological and dominant theorizing in HRD. The author examines what it means when HRD writings are said to be gendered; how the political and processual dynamics of doing HRD can be understood; how the differences for doing gender, doing HRD and embodying HRD can be unravelled; and how feminist modes of inquiry can engender the value of embodied reflexivity. Weaving together literature strands from gender and education, gender and organization, and women's studies and feminist writings, the paper provides a foundational framework for how HRD scholars can re-imagine new knowledge and inject notions of the feminine and difference in HRD writings. The analysis focuses on three interrelated areas and their implications for feminist critique: the importance of examining language and discourse in HRD; the performing body in HRD; and, finally, feminist embodied reflexivity. It is argued that the HRD scholarly community should consider critical modes of inquiry to refresh and renew HRD theory building, specifically that we should examine conceptualizations of the feminine and difference in HRD writings in order to aid transformational practice.     

Decentralizing Risk Analysis in Large Engineered Systems: An Approach to Articulating Technical and Socioorganizational Dimensions of System Performance1

Nuclear power production in France, as the domain of one national utility and one reactor builder, has a standardized profile of technical installations, safety procedures, and personnel qualifications. Despite this relative homogeneity, discrepancies are observed from one production unit to another, notably in the area of worker-safety performance. There is a strong implication for risk analysis: varying performance cannot be attributed solely to the technical dimensions of equipment, procedures, and human skills. The authors retain as a working hypothesis that safety performance is an outcome of interactions between technical and organizational factors. Traditional risk analysis appears to be underequipped to represent such interactions. The notion of decentralized risk analysis (DRA) is introduced as a means of achieving this goal. A program of applied research carried out in a NPP facility is presented. It aims at increasing, across plant work structure, knowledge and control of these interactions specific to the given context. Systematic measurements and feedback of social representations are performed, using a three-dimensional factor space of individual and organizational values. Direct involvement of the total plant population, transfer of analytic tools, methodological continuity, interactive elaboration of data, coordination of different levels of findings with operations, follow-up and feedback of measured change, are the main features of this DRA process. In the case cited, improvement observed in safety performance parallels changes in measured social representations. The value of DRA for articulating technical and organizational dimensions of risk, and for integrating information into decision-making, is argued.     

Re-engineering high risk, high complexity industries through multiple level technological learning A case study of the world nuclear power industry

Applying lessons learned at the national, the utility, and the plant level, from selected segments of the world-wide nuclear power industry, might facilitate an environmentally acceptable renaissance of the U.S. nuclear power industry through re-engineering it. Elements of this learning from experience process can be found: (a) at the national level in Europe, Japan, and the U.S., (b) at the utility level in two New York State nuclear power utilities, Niagara Mohawk and New York Power Authority, the Tenessee Valley Authority, and Duke Power and Light in the U.S., in Ontario Hydro in Canada, and in the Electricité de France (EdF) in France, and (c) at the plant level in several of these utilities. At the core of all the continuous quality improvement and re-engineering programs, lies this twofold mission: (a) to insulate society from foreseeable and unacceptably high environmental risks, and (b) to continuously improve the design and management of nuclear technology (including nuclear waste management and environmental risk management systems) by learning, learning how to learn, and learning to learn-how-to-learn, both explicitly and tacitly, through feedback from individual and organizational experience.     

Universal versus contextual effects on TQM: a triangulation study using neural networks

The objective of this study is to extend previous research on total quality management (TQM)-context-performance relationships and ‘fit’ using multiple methods. We combine artificial neural networks (ANNs) with structural equation modelling (SEM) to analyse several hypotheses and propositions. This is the first study in this area of research that utilises ANNs and a triangulation technique in the presence of several contextual factors. The SEM analyses suggest that company size and industry type may have contingency effects on some of the TQM practices and/or TQM-performance relationships. However, the ANN models have shown that these two contingency factors do not moderate TQM outcomes, implying that all organisations can benefit from TQM regardless of size and type. As well, these models show that formal TQM implementation and/or ISO certifications do not add any predictive power to the ANN models except in one case: TQM implementation and/or ISO certification added to organisational effectiveness and customer results to predict financial and market (F&M) results. The results further indicate that even though implementing TQM alone has a bigger impact on F&M results than obtaining ISO certification alone, combining the two will have an even greater impact on these results. Joint implementation leads to greater improvements in organisational effectiveness, which, in turn, has a positive effect on customer results and consequently F&M results. This is a unique finding within the context of moderator effects on TQM-performance relationships.