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Vigilance - 91 entries found

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CIS 12-0164 Kubo T., Takahashi M., Sato T., Sasaki T., Oka T., Iwasaki K.
Weekend sleep intervention for workers with habitually short sleep periods
This study was conducted to determine whether extended sleep time during the weekend improves alertness and performance during the subsequent week for workers who are habitually short on sleep time. Daytime employees in the manufacturing industry with mean weekday sleep ¿6 hours participated in a study that lasted three successive weeks. Participants were instructed to stay in bed for eight hours or more between 22:00 to 09:00 hours on weekends during the first week as a sleep intervention condition and keep their habitual sleep-wake patterns as a habitual weekend sleep condition beginning the weekend of the second week through Thursday of the third week. Half the participants underwent the conditions in one order and the other half in the reverse. Sleep was monitored by an actigraph. A psychomotor vigilance task, subjective fatigue and blood pressure were measured on Monday and Thursday during the afternoon each week. Sleep duration on weekends was approximately two hours longer per day during the intervention. However, sleep duration during weekdays following the intervention returned to shorter periods. Significantly shorter reaction times and a smaller number of lapses on the psychomotor vigilance task were found on Mondays after the intervention than after the habitual weekend sleep. The opposite results, however, were observed on Thursdays. Sleep extension on weekends may be effective in improving alertness and performance during the first days in subsequent weeks among workers with short sleep times. These benefits might be maintained if sufficient sleep duration continues.
Scandinavian Journal of Work, Environment and Health, Sep. 2011, Vol.37, No.5, p.418-426. Illus. 35 ref.
Weekend_sleep_intervention_[BUY_THIS_ARTICLE] [in English]

CIS 11-0734 Ferguson S.A., Paech G.M., Dorrian J., Roach G.D., Jay S.M.
Performance on a simple response time task: Is sleep or work more important for miners?
The purpose of this study was to investigate the impact of work- and sleep-related factors on an objective measure of response time in a field setting. Thirty-five mining operators working 12h shifts completed daily sleep and work diaries, wore activity monitors continuously and completed palm-based psychomotor vigilance tests at the start and end of each shift. Linear mixed models were used to test the main effects on response time of roster, timing of test, sleep history and prior wake. The time at which the test occurred was a significant predictor of response time, with the end of night shifts being associated with significantly slower response times than the start of night shifts, and the start or end of day shifts. Further, the amount of sleep obtained in the 24h prior to the test was also a significant predictor of response time. The results suggest that the end of night shift is associated with changes in response time indicative of performance impairments. The immediate sleep history was also predictive of changes in response time, with lower amounts of prior sleep related to slower response times. The current data provides further evidence that sleep is a primary mediator of performance, independent of roster pattern.
Applied Ergonomics, 2011, Vol.42, p.210-213. Illus. 35 ref.

CIS 11-0728 Gershon P., Shinar D., Oron-Gilad T., Parmet Y., Ronen A.
Usage and perceived effectiveness of fatigue countermeasures for professional and nonprofessional drivers
The objective of this study was to compare usage patterns and evaluate the perceived effectiveness of different coping behaviours adopted by professional and nonprofessional drivers in order to maintain alertness. It was conducted by means of a questionnaire survey among 100 professional and 90 nonprofessional drivers. Listening to the radio and opening the window were the most frequently used and also perceived as highly effective coping behaviours by both groups of drivers. Talking on a cellular phone or with a passenger were more frequently used by nonprofessional drivers whereas, planning rest stops ahead, stopping for a short nap and drinking coffee were more frequently used by professional drivers. These methods were also perceived as more effective by professional than by the nonprofessional drivers and their usage frequency highly correlated with their perceived effectiveness. Nonprofessional drivers counteract fatigue only at the tactical/maneuvering level of the drive. Hence, they tend to adopt methods that help them pass the time and reduce their feeling of boredom but do not require advance preparations or adjustments in the driving. In contrast, professional drivers counteract fatigue also at the strategic/planning level of driving, and use a much larger repertoire of coping behaviours.
Accident Analysis and Prevention, May 2011, Vol.43, No.3, p.797-803. 27 ref.

CIS 11-0727 Williamson A., Friswell R.
Investigating the relative effects of sleep deprivation and time of day on fatigue and performance
The objective of this study was to examine the relative effects of time of day and sleep deprivation on fatigue and performance. Two independent groups were exposed to 28 h of sleep deprivation beginning at 06:00 h for one group (39 participants) and at 00:00 h for the other (22 participants). By varying the start time for the two groups, but keeping constant the duration of sleep deprivation, the effects of variations in the time of day of testing were examined. For the 06:00 h start group, the longest period without sleep occurred close to the low point of the circadian rhythm. For the 00:00 h start group, the circadian low point coincided with only two to six hours of sleep deprivation. Performance was evaluated two-hourly using computer-based cognitive performance and memory tests, together with subjective fatigue ratings. Both time of day and sleep deprivation affected performance. The implications of these findings for fatigue management are discussed.
Accident Analysis and Prevention, May 2011, Vol.43, No.3, p.690-697. Illus. 22 ref.


CIS 11-0129 Sato T., Kubo T., Ebara T., Takeyama H., Inoue T., Iwanishi M., Tachi N., Itani T., Kamijima M.
Brief hourly exercise during night work can help maintain workers' 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, a 15-min test and a 15-min break. The study included two experimental conditions: hourly exercise for 3 min during breaks, and a control condition, without exercise during the breaks. Throughout the test period, work performance in the last 10 min of each 30-min task was better under the exercise condition than under the control condition. Implications of these and other findings are discussed.
Industrial Health, July 2010, Vol.48, No.4, p.470-477. Illus. 41 ref.
Brief_hourly_exercise.pdf [in English]

CIS 10-0074 Aptel M., Bonneterre V., De Gaudemaris R., Paris C., Lasfargues G., Chamoux A.
National occupational disease surveillance and prevention network (RNV3P): A standing network of experts for the advancement of occupational safety and health
Le Réseau national de vigilance et de prévention des pathologies professionnelles (RNV3P) [in French]
This article describes the structure and approach adopted by the National occupational disease surveillance and prevention network (French acronym RNV3P), based on the centers for occupational disease consultation (French acronym CCPP) of university hospitals. The network comprises 32 CCPPs, spread across the territory of France.
2nd Quarter 2010, No.122, p.167-183. Illus. 25 ref.$File/TC132.pdf [in French]


CIS 09-951 Halvani G.H., Zare M., Mirmohammadi S.J.
The relation between shift work, sleepiness, fatigue and accidents in Iranian industrial mining group workers
The aim of this cross-sectional study was to examine the rate of fatigue and sleepiness among shift and non-shift workers and its relation to occupational accidents. The study included 137 shift workers of Iranian Industrial Mining Group and 130 non-shift workers as controls. A multi-part questionnaire including demographic characteristics, Piper Fatigue Scale and Epworth Sleepiness Scale were applied. The mean of PFS scores in the two groups was significantly different, but the difference in the mean of ESS scores was not significant. Shift workers who reported accidents had a higher score on fatigue than shift workers reporting no accidents whereas the difference in the number of accidents in the two groups was not significantly related to the rate of sleepiness. The rate of fatigue and the number of the work accidents were higher in shift workers. Fatigue was also more strongly associated with occupational accidents than with sleepiness. Results seem to indicate that the evaluation of fatigue as compared to sleepiness is a more accurate factor for preventing occupational accidents.
Industrial Health, Mar. 2009, Vol.47, No.2, p.134-138. Illus. 24 ref. [in English]

CIS 09-471 Killgore W.D.S., Grugle N.L., Reichardt R.M., Killgore D.B., Balkin T.J.
Executive functions and the ability to sustain vigilance during sleep loss
It has been suggested that individuals with higher activation of the prefrontal cortex may be less vulnerable to fatigue. This hypothesis was tested in a sample of 54 healthy volunteers who were assessed bi-hourly for psychomotor vigilance during 41h of sleep deprivation. Subsets of these subjects, representing the top and bottom quartiles based on their vigilance performance were compared with respect to baseline neuro-cognitive abilities. The sleep deprivation resistant group scored significantly higher than the sleep deprivation vulnerable group on all three baseline tasks assessing prefrontal neuro-cognitive abilities. Other findings are discussed.
Aviation, Space, and Environmental Medicine, Feb. 2009, Vol.80, No.2, p.81-87. Illus. 62 ref.


CIS 09-723 Ebara T., Kubo T., Inoue T., Murasaki G.I., Takeyama H., Sato T., Suzumura H., Niwa S., Takanishi T., Tachi N., Itani T.
Effects of adjustable sit-stand VDT workstations on workers' musculoskeletal discomfort, alertness and performance
Adjustable sit-stand workstations, which are designed to allow workers to sit and stand autonomously while working, were examined to identify the effects on workers' musculoskeletal comfort, alertness and performance. Twenty-four healthy subjects participated in the study. The subjects were required to do an English transcription task for 150 min using standard and high-chairs, under various sitting and standing conditions and sequences. Findings are discussed. This study revealed that although the use of sit-stand workstations can contribute to keeping workers' arousal level steady, it has an adverse effect on musculoskeletal comfort.
Industrial Health, Sep. 2008, Vol.46, No.5, p.497-505. Illus. 20 ref. [in English]

CIS 09-473 Takayama L., Nass C.
Assessing the effectiveness of interactive media in improving drowsy driver safety
A total of 79 participants used a driving simulator while interacting with a language-learning system that was either passive (drivers merely listen to phrases in another language) or interactive (drivers verbally repeat those phrases). Participants included drowsy and non-drowsy drivers, on both monotonous and varied driving courses. Among the main findings: drowsy drivers preferred and drove more safely with interactive media; the interactive media did not negatively affect non-drowsy driver safety; drivers drove more safely on varied driving courses than on monotonous ones. Implications of these findings are discussed.
Human Factors, Oct. 2008, Vol.50, No.5, p.772-781. 65 ref.

CIS 09-62 Talmage J.B., Hudson T.B., Hegmann K.T., Thiese M.S.
Consensus criteria for screening commercial drivers for obstructive sleep apnea: Evidence of efficacy
To validate the recently published consensus criteria for screening commercial drivers for obstructive sleep apnoea (OSA), a large sample of commercial drivers was screened for OSA at an occupational medicine clinic and those screening positive were referred for overnight polysomnography. Among the 1443 individuals drivers examined, 190 (13%) of screened positive for OSA. Of these, 134 underwent polysomnography and 94.8% had OSA. The proposed screening criteria were found to have a high predictive value in this population. This study lends further support for mandatory screening of commercial drivers for OSA.
Journal of Occupational and Environmental Medicine, Mar. 2008, Vol.50, No.3, p.324-329. 9 ref.

CIS 09-74 Viitasalo K., Kuosma E., Laitinen J., Härmä M.
Effects of shift rotation and the flexibility of a shift system on daytime alertness and cardiovascular risk factors
This study was conducted to evaluate the effects of changes in shift rotation (direction and speed) and in the flexibility of the shift system on alertness and cardiovascular risk factors. Altogether 84 male maintenance workers of an airline in Finland working in a backward-rotating shift system volunteered for the study, among whom 40 changed to a rapidly forward-rotating shift system, 22 to a more flexible shift system and 22 remained with the old shift system. Data on health effects were collected by means of clinical examinations, blood tests and questionnaires before and after the shift changes. Analyses of variance were used to study associations of cardiovascular risk factors and daytime sleepiness according to the change in shift systems. It was found that that faster speed together with a change to the forward direction in shift rotation alleviates daytime sleepiness. Furthermore, increased flexibility has favourable effects on blood pressure. Other findings are discussed.
Scandinavian Journal of Work, Environment and Health, June 2008, Vol.34, No.3, p.198-205. Illus. 34 ref.


CIS 07-1218 Otmani S., Rogé J., Muzet A.
Sleepiness in professional drivers: Effect of age and time of day
The effects of age and time of day on objective and subjective sleepiness in professional drivers were investigated during a simulated driving task. Thirty-six young and middle-aged professional male drivers, free from any sleep disorder, took part in two simulated driving sessions; one carried out in the afternoon, the other at night. Half of each age group drove in light traffic conditions while the other half drove in heavy traffic. Throughout the driving task, subjects' electroencephalogram and Karolinska sleepiness scale scores were recorded. Visual analogue scales measuring alertness and sleepiness levels were also completed before and after the driving. After each session, subjects filled out the NASA-TLX questionnaire and were asked if they had felt sleepy during the driving. The young drivers presented a significant decrease in alertness in the low traffic condition and a strong propensity to sleep during the night test in contrast to middle-aged drivers.
Accident Analysis and Prevention, Sep. 2005, Vol.37, No.5, p.930-937. Illus. 30 ref.

CIS 07-1217 Bunn T.L., Slavova S., Struttmann T.W., Browning S.R.
Sleepiness/fatigue and distraction/inattention as factors for fatal versus nonfatal commercial motor vehicle driver injuries
A retrospective population-based case-control study was conducted to determine whether driver sleepiness/fatigue and inattention/distraction increase the likelihood that a commercial motor vehicle collision will be fatal. Based on the Kentucky Collision Report Analysis for Safer Highways (CRASH) electronic database, 1998-2002, cases were identified as commercial vehicle drivers who died following a collision accident and controls were drivers who survived an injury collision. Cases and controls were matched by vehicle and roadway type. Conditional logistic regression was performed. Driver sleepiness/fatigue, distraction/inattention, 51 years of age and older, and non-use of safety belts increased the odds of fatal commercial vehicle collision accidents. Implications of these findings are discussed.
Accident Analysis and Prevention, Sep. 2005, Vol.37, No.5, p.862-869. Illus. 31 ref.

CIS 06-736 Wright N., Powell D., McGown A., Broadbent E., Loft P.
Avoiding involuntary sleep during civil air operations: Validation of a wrist-worn alertness device
This study evaluated the effectiveness of an alertness device based on wrist inactivity to detect the onset of sleep among airline pilots during flight. The device was worn by 21 pilots during a long (9h) flight. The presence of sleepiness and sleep was determined by means of electroencephalogram (EEG) and electrooculogram (EOG) recordings during the entire flight. The alertness device was found to be an effective method for preventing accidental sleep.
Aviation, Space, and Environmental Medicine, Sep. 2005, Vol.76, No.9, p.847-856. Illus. 26 ref.

CIS 06-469 Lamond N., Darwent D., Dawson D.
Train drivers' sleep and alertness during short relay operations
Within Australia, there has been a recent increase in relay working in rail transport operations. To address concerns about the amount of sleep by drivers in relay vans and resulting potential deficits in alertness, the current study assessed the sleep behaviour and alertness of 15 train drivers working short (<48h) relay operations. In total, drivers obtained 8-12h of sleep during the relay trip, which took approximately 40h. Overall, they reported that they felt more alert following each sleep period. Drivers were able to sustain attention during the 10-min vigilance tasks administered before and after each shift. These findings suggest that the amount of sleep obtained in crew vans during short relay operations is sufficient to maintain alertness during the trip. The importance of scheduling shifts to maximize the number of sleep opportunities between 10 pm and 7 am is emphasized.
Applied Ergonomics, May 2005, Vol.36, No.3, p.313-318. Illus. 22 ref.


CIS 06-730 Tirilly G.
The impact of fragmented schedules at sea on sleep, alertness and safety of seafarers
El impacto de las jornadas fragmentadas en la mar sobre el sueño, la capacidad de alerta y la seguridad de los marinos [in Spanish]
Most work schedules at sea rely on the watchkeeping system. This study examines the work/rest rhythm among seafarers and its effect on sleep and alertness. Two studies were conducted, one aboard a trawler and the other on an oceanographic vessel. Results indicate that sleep is fragmented into 2-3 episodes on the oceanographic vessel and 5-6 episodes on the trawler. Despite the fragmentation of the sleep, the 24h alertness rhythm was maintained, although with an impairment at night and a pronounced dip in the afternoon (coinciding with the need for a nap). The decreased alertness being linked to a much higher risk of accident, this risk factor is elevated at night. However the study shows that numerous work- and environmental-related factors play an important role in maintaining alertness level and have to be taken into account when addressing safety at sea.
Medicina Marítima, Dec. 2004, Vol.4, No.2, p.96-105. Illus. 15 ref.

CIS 05-243 Boyer C., Manillier P., Marchon-Jourdan M.F., Meyer A., Ouallet C., Trimbach M., Wargon C., Montéléon P.Y.
Evaluation of sleep and vigilance disturbances in a population of employees of SMEs in Ile-de-France
Evaluation des troubles du sommeil et de la vigilance dans une population de salariés de PME de l'Ile-de-France [in French]
The objective of this study was to assess the prevalence of sleep and vigilance disturbances in a group of employed persons and to explore possible relationships between these disturbances and the conditions of work. An anonymous standardized questionnaire was submitted to randomly-selected workers. The insomnia criteria defined in DSM IV were used and vigilance was expressed according to the Epworth scale. The responses were subjected to statistical analysis. 1410 workers (32.2%) suffered from insomnia. Occupational factors responsible for this insomnia included having very physically-demanding work (relative risk RR=2.25), very stressful work (RR=2,20), monotonous work (RR=1.65) and a noisy environment (RR=1.22). 16.1% of workers showed an Epworth score greater than 10, which is indicative of reduced vigilance.
Cahiers de médecine interprofessionnelle, 2004, Vol.44, No.2, p.157-179. 40 ref.

CIS 04-727 Barthe B., Quéinnec Y., Verdier F.
Analysis of work activity during night shifts: A review of 25 years of research and future outlook
L'analyse de l'activité de travail en postes de nuit: bilan de 25 ans de recherches et perspectives [in French]
This article consists of a review of published literature on shift work drawn from the fields of psychophysiology, chronobiology and ergonomics. It is not possible to highlight all the difficulties faced by workers during shift work or night work by limiting the investigations to the consequences on job performance alone. New models that take into account circadian and homeostatic factors are an attempt to explain the specific nature of night work and its relationship with changes in vigilance. The search for solutions is discussed from the vantage points of work organization (for example the introduction of night naps) and the cooperative aspects of work.
Travail humain, Jan. 2004, Vol. 67, No.1, p.41-61. Illus. 54 ref.


CIS 05-476 Åkerstedt T., Knutsson A., Westerholm P., Theorell T., Alfredsson L., Kecklund G.
Work organisation and unintentional sleep: Results of the WOLF study
Falling asleep at work is receiving increasing attention as a cause of work accidents. This study investigates which variables (related to work, lifestyle, or background) are related to the tendency to fall asleep unintentionally, either during work hours, or during leisure time. 5589 individuals responded to a questionnaire, and a multiple logistic regression analysis of the cross-sectional data was used to estimate the risk of falling asleep. The prevalence for falling asleep unintentionally at least once a month was 7.0% during work hours and 23.1% during leisure time. The risk of unintentional sleep at work was related to disturbed sleep, shift work, and higher socioeconomic group. Being older, a woman and a smoker were associated with a reduced risk of unintentionally falling asleep at work. Work demands, decision latitude at work, physical load, sedentary work, solitary work, extra work, and overtime work were not related to falling asleep at work. With respect to falling asleep during leisure time, disturbed sleep, snoring, high work demands, being a smoker, not exercising, and higher age (>45 years) became risk indicators.
Occupational and Environmental Medicine, Sep. 2002, Vol.59, No.9, p.595-600. 55 ref.


CIS 03-1473 Bobko N.
Effects of stress on psychophysiological parameters of electricity distribution network controllers in Ukraine
Electricity distribution controllers are responsible for balancing supply and demand for electricity under planned and unforeseen equipment shut-downs and network disruptions. To study the effects of stress on the cognitive performance and the cardiovascular system of controllers, 16 controllers working 12-hour shifts were studied. A five-point scale was used to estimate the perceived level of stress. The most pronounced changes in heart rate, circulatory minute volume and Kerdo's vegetative index were found during the first day shift and less pronounced changes appeared during the first night shift. Effects of stress on the studied parameters were not found during the second consecutive day or night shift. Increased stress causes the activation of psychophysiological functions that are indispensable for ensuring work efficiency under increased production demands. However, the necessary activation could not be maintained during the second consecutive 12-hour shifts. There was no observed effect of stress on short-term memory.
Journal of Human Ergology, Dec. 2001, Vol.30, No.1-2, p.351-355. Illus. 20 ref.

CIS 02-484 Özkan-Rabret E.
8th Research day of the Inter-University Institute of Occupational Medicine of Paris-Ile-de-France: Sleep - vigilance - work
8ème Journée de recherche de l'Institut interuniversitaire de médecine du travail de Paris-Ile-de-France: sommeil - vigilance - travail [in French]
Review article on the topics presented at the 8th inter-university occupational medicine research day of Paris-Ile-de-France held in Paris, 23 March 2001. Contents: biological clocks and rules affecting alternating sleep and alert periods; insomnia and poor quality sleep, including evaluation tools; hypersomnia; drowsiness when driving; intake of medicines and drowsiness; drowsiness and aptitude for vigilance tasks; drowsiness assessment scales.
Cahiers de médecine interprofessionnelle, 2001, Vol.41, No.2, p.189-202.


CIS 02-1763 Bertini M., Fattorini E.
The effects of monotonous tasks on ultradian and circadian changes in alertness and mood and EEG levels of drowsiness for VDT work activities
Effetti della monotonia del compito sulle variazioni ultradiane e circadiane della vigilanza e dell'umore e sui livelli di sonnolenza EEG nelle attività lavorative ai videoterminali [in Italian]
The vigilance and wakefulness of six male workers on computer terminals were evaluated by examining electroencephalographic changes in their sleep patterns. The changes can be attributed to relaxed vigilance subsequent to the performance of monotonous work. This kind of work may result in unforeseeable periods of sleep during the performance of the task.
Prevenzione oggi, Apr.-June 2000, Vol.12, No.2, p.25-34. Illus. 20 ref.

CIS 00-1175 Mitchell R.J., Williamson A.M.
Evaluation of an 8 hour versus a 12 hour shift roster on employees at a power station
The objective of this study was to examine the changeover from an 8h roster to a 12h roster in a power station. On-shift performance, general health and well-being, sleep and mood behaviour, as well as absenteeism and accident data were examined. Results suggest that the domestic and social life of workers was markedly improved under the 12h roster. Improvements in physical health, sleeping behaviour and mood state of employees were also documented On-shift performance measures showed an increase in error rates at the end of a 12h shift.
Applied Ergonomics, Feb. 2000, Vol.31, No.1, p.83-93. Illus. 37 ref.


CIS 02-483 Fenner P., Leahy S., Buhk A., Dawes P.
Prevention of drowning: Visual scanning and attention span in lifeguards
The safety of the swimming public is dependent on effective continuous scanning techniques by lifeguards patrolling the area. Similar scanning skills are needed in other professions which require concentration for repetitive, monotonous or boring tasks. These include airline pilots, air search and rescue personnel, and long-distance train or bus drivers. To date, very little has been published on effective methods for lifeguards to use when scanning their area of responsibility. Techniques that influence visual scanning effectiveness and concentration spans, or assist in the prevention of boredom, are presented and discussed.
Journal of Occupational Health and Safety - Australia and New Zealand, Feb. 1999, Vol.15, No.1, p.61-66. 24 ref.

CIS 99-2084 McPherson G.
Too tired to stay alert
The offshore environment is a dangerous home to workers who may, for half their lives, work 12-hour shifts for up to 14 consecutive days. Their particular job and lifestyle is designed to be repetitive but this habitual life can lead to fatigue which has been cited as a cause of a significant number of accidents offshore. Research into fatigue within this specific occupational community indicates the extent to which alertness is affected by fatigue. The results have implications for those working in a wider field. Topics: conditions of work; fatigue; offshore oil extraction; relaxed vigilance; shift work; work time schedules.
Safety and Health Practitioner, May 1999, Vol.17, No.5, p.16-18. Illus. 5 ref.

CIS 99-1711 Tucker P., Smith L., Macdonald I., Folkard S.
Distribution of rest days in 12 hour shift systems: Impacts on health, wellbeing, and on shift alertness
The effects of distribution of rest days in 12 hour shift systems were investigated. An abridged version of the standard shiftwork index which included retrospective alertness ratings was completed by a large sample of industrial shiftworkers. The respondents worked 12 hour shift systems that either did or did not incorporate breaks of >24 hours between the blocks of day and night shifts. Systems which incorporated rest days between the day and night shifts were associated with slightly higher levels of on-shift alertness, slightly lower levels of chronic fatigue, and longer sleep durations when working night shifts and between rest days. Early changeovers were associated with shorter night sleeps between successive day shifts, but longer and less disturbed day sleeps between night shifts. The distribution of rest days in 12hour shift systems had only limited effects on the outcome measures, although the few modest differences that were found favoured systems which incorporated rest days between the day and night shifts. Topics: fatigue; questionnaire survey; shift work; sleep; social aspects; state of health; vigilance; work-rest schedules.
Occupational and Environmental Medicine, Mar. 1999, Vol.56, No.3, p.206-214. Illus. 24 ref.


CIS 96-1891 Sato M., Toma A., Nakayama K., Takahashi M.
Physiological and psychological effects of illuminance in an office space
Shitsumu kūkan ni okeru sh-ōdo no seiri shinriteki eikyō [in Japanese]
To evaluate the physiological and psychological effects of illuminance levels during the performance of monotonous tasks, subjects performed work on computer terminals in a simulated office space. The lighting levels were 200, 500, 1250 and 3125 lx. The variables measured were electroencephalogramme (EEG), finger photoelectric plethysmogramme (PTG), heart rate and score on the Kansei Gakuin Sleepiness Scale (KSS). The subjects were more alert and relaxed at 500 and 1250 lx than at higher or lower levels.
Journal of the Illuminating Engineering Institute of Japan, May 1996, Vol.80, No.5, p.23-30. Illus. 18 ref.


CIS 01-920 Coblentz A.M., Cabon P.
Effects of monotony and work-time schedules on operator vigilance and performance
Effets de la monotonie et de l'organisation des horaires de travail sur la vigilance et la performance des opérateurs [in French]
There are ever higher demands for operator vigilance as a result of increasing automation in industrial and transportation systems. The monotony of tasks, night work and irregular working hours give rise to unfavourable conditions with respect to the ability to maintain high levels of vigilance. This articles discusses these issues and proposes solutions applicable to the road and air transport sectors. Topics covered: state of hypovigilance during driving; detecting the lowering of vigilance under real working conditions; vigilance, performance and circadian rhythms; rest periods. Proposals are made for improving the organisation of work-rest cycles, applicable both to rail and air transportation.
Encyclopédie médico-chirurgicale, Toxicologie-Pathologie professionnelle, 4th Quarter 1994, No.105, 8p. Illus. 30 ref.

CIS 96-1465 Schweizer G.
The influence of the microclimate in commercial vehicles on the driver's performance
Der Einfluss des Mikroklimas im Nutzfahrzeug auf die Leistungsfähigkeit des Fahrers [in German]
The results of simulation tests are used to illustrate the effects of temperature rises in the driver's cab. An increase to 30°C increased the number of errors by 28%. At an increase to 35°C the errors rose by 40%. Present air conditioning systems for commercial vehicles are helpful in maintaining a comfortable climate that neither lowers the attention-span of drivers nor increases their reaction time.
ATZ, July-Aug. 1994, Vol.96, No.7-8, p.406-410. Illus. 7 ref.

CIS 95-375 Wærsted M., Bjørklund R.A.
The effect of motivation on shoulder-muscle tension in attention-demanding tasks
In four separate experiments using a visual display unit based complex reaction-time task, motivation was induced by means of continuous feedback on the level of performance or by means of a money reward for good performance. In all experiments, motivation improved the performance, but an increase in the psychogenic shoulder-muscle tension was only observed in the money-reward condition. Results are discussed in terms of whether this difference in the muscle-tension response is due to changes in the subjects' attitude unrelated to performance or due to a superior performance in the money-reward condition.
Ergonomics, Feb. 1994, Vol.37, No.2, p.363-376. Illus. 32 ref.


CIS 94-1443 Galinsky T.L., Rosa R.R., Warm J.S., Dember W.N.
Psychophysical determinants of stress in sustained attention
The effects of the sensory modality of signals (audition and vision) and the background event rate (5 and 40 events/min) on task-induced stress were examined for a group of 40 subjects. Restlessness and subjective fatigue increased dramatically across a 50-min watch in all conditions. Stress effects were most notable in the case of visual monitoring but were unrelated to variations in the event rate. Hence, from a psychophysical perspective, the stress of sustained attention seems to be identified more specifically with the sensory modality of signals rather than with the event rate context in which they appear.
Human Factors, Dec. 1993, Vol.35, No.4, p.603-614. 48 ref.

CIS 94-1090 Cail F., Mouzé-Amady M.
Assessment of operator stress in a simulated process control task
Evaluation du stress des opérateurs d'un contrôle de processus simulé [in French]
This study involving six subjects assessed operator stress during computer simulated process control operations by quantifying psychophysiological and hormonal changes before, during and after the task, without outside stress factors and with a combination of physical stressors (poor lighting and noise). Electroencephalograph and electrocardiograph readings were recorded continuously for 30 minutes before the task, during the task and for 30 minutes after the end of the task to assess the stress caused by the task and the environment. Saliva samples were taken at regular intervals for determination of cortisol as a measure of stress. After a complex screen task, functional recovery takes longer if rest is taken in a noisy environment and with bright front-on lighting. Recommendations are therefore proposed for the organization of break periods and rest areas for video display workers in industry.
Cahiers de notes documentaires - Hygiène et sécurité du travail, 3rd Quarter 1993, No.152, Note No.1939-152-93, p.477-482. Illus. 26 ref.


CIS 95-599 Guard duty and occupational safety
Bewachung und Arbeitssicherheit [in German]
Security officers protect people and property against crimes and fires and take care of the transport of money. The hazards they may face include falls, exposure to pollutants and radiation as well as attacks with firearms. They are required to have some knowledge of civil and criminal law and to be well versed in coping with people. For their safety they need in-depth instruction concerning guard duties and the equipment they have to deal with. They must be furnished with protective clothing and firearms. The safety measures required for the transport of money in Germany are outlined.
Sicherheitsreport, Apr. 1992, No.2, p.4-16. Illus.

CIS 94-891 French Society of Occupational Medicine and Hygiene - Meetings of 14 Jan., 11 Feb., 10 Mar. and 14 Apr. 1992
Société de médecine et d'hygiène du travail - Séances du 14 janvier, 11 février, 10 mars et 14 avril 1992 [in French]
Topics of papers presented at the meetings of the French Society of Occupational Medicine and Hygiene (France, 14 Jan., 11 Feb., 10 Mar., 14 Apr. 1992): ligament hyperlaxity and work aptitude; respiratory diseases among jewellers; the industrial physician and the employment of handicapped workers in France (preliminary results of a survey); rhinitis and asthma due to latex are compensable occupational diseases in France; assistance provided to the industrial physician in France to promote the employment of handicapped workers; two cases of occupational asthma due to Chloramine T; an accident due to carelessness and caused by the crushing of a worker between two trucks in a garage; alertness in relation to work among interns on call; risk assessment of a new activity: the removal of graffiti; feasibility study of an olfactometry test in occupational medicine.
Archives des maladies professionnelles, 1992, Vol.53, No.7, p.645-664.


CIS 91-2083 Rosa R.R.
Performance, alertness, and sleep after 3-5 years of 12h shift: A follow-up study
Control room operators at a continuous processing plant have been working a 12h/3-4 day rotating shift schedule for over 3 years. After 7 months on this schedule, initial assessment indicated decrements in performance and alertness, and a mild to moderate sleep debt, when the 12h shift schedule was compared to the previously-worked 8h shift schedule. In an effort to track long-term adaptation to the schedule, a 3-5 year follow-up evaluation using the same set of measures was conducted. Long-term follow-up testing revealed persistent decrements in performance and alertness attributable to 12h shifts, and 1-3h reduction in total sleep time after 12h 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 12h shift schedule at this worksite indicates that the workers are willing to tolerate extra fatigue to derive other benefits from this schedule.
Work and Stress, Apr.-June 1991, Vol.5, No.2, p.107-116. Illus. 19 ref.

CIS 91-1690 Cail F., Mouzé-Amady M.
Physical hazards and work with visual display units in industry - Experimental simulation
Nuisances physiques et travail sur écran en industrie - Simulation expérimentale [in French]
This study investigated the behavioural and psychophysiological changes during a simulated process control task performed under single and combined physical stressors. Twenty-four subjects took part in the task on a visual display unit (VDU), in 4 experimental conditions: adequate lighting (control); noise; inadequate lighting; noise and inadequate lighting. Response times (performance), electroencephalogrammes, electro-oculogrammes and heart rate (vigilance indicators) were continuously recorded during the task. The main results show that the longest response times and the highest activation levels occurred in a multistressor environment. This suggests that combined inadequate lighting and noise impairs the operator's efficiency in process control on a VDU. Recommendations are made for improving the situation in such workplaces.
Cahiers de notes documentaires - Sécurité et hygiène du travail, 1st Quarter 1991, No.142, Note No.1816-142-91, p.71-77. Illus. 15 ref.

CIS 91-1398 Stanton N.A., Booth R.T.
Cognitive aspects of alarm handling
In principle, alarm systems should aid central control room operators by relieving them of continuous monitoring of every process variable. In reality, however, these systems have introduced a new set of problems. This paper examines the nature of alarm handling and suggests how future research might further explore the issues raised.
Journal of Health and Safety, Mar. 1991, No.6, p.45-54. Illus. 22 ref.


CIS 92-343 Noy Y.I.
Attention and performance while driving with auxiliary in-vehicle displays
Attention et performance pendant la conduite avec des affichages auxiliaires de bord [in French]
A series of 3 experiments was conducted to investigate basic human factors issues relating to the design and use of auxiliary in-vehicle displays. A total of thirty healthy male and female students with a minimum of 3 years' driving experience participated in these studies. Subjects drove in a moving-base driving simulator and performed auxiliary cognitive tasks on a CRT display located on the right side instrument panel. Subjects were instructed to perform both the auxiliary task and the driving task to the best of their abilities but to give priority to driving. The results indicated that performing auxiliary tasks while driving can significantly degrade performance.
Road Safety and Motor Vehicle Regulation, Transport Canada, Ottawa, Ontario K1A 0N5, Canada, 1990. 130p. Illus. 153 ref.

CIS 91-477 Dvorak H.
Possibilities of measuring effects on skills and fatigue - Problems with repeated vigilance testing
Möglichkeiten der Messung von Übungs- und Ermüdungseffekten - Probleme bei der Wiederholung einer Daueraufmerksamkeitsprüfung [in German]
A standardised vigilance and attention-span test was administered to 125 employees of the German Federal Railways. After periods ranging from 4 weeks to 2 years these employees were retested. Cognitive performance changes between the 2 perception tests were compared with those in a control group performing the 2 tests consecutively without a break. Both groups performed significantly better in the second test. Performance improvement was independent of the interval between the first and second test.
Arbeitsmedizin - Sozialmedizin - Präventivmedizin, 1990, Vol.25, No.2, p.54-58. Illus. 27 ref.

CIS 91-698 Eilers K., Nachreiner F., Böning E.
Subjective scaling of mental workload. Part 2: Testing the validity of standardised judgements in a field study
Zur subjektiven Skalierung psychischer Beanspruchung. Teil 2: Überprüfung der Validität verankerter Relativurteile in einer Felduntersuchung [in German]
The usefulness of rating scales in assessing the mental workload was studied with 40 persons performing 4 different sorting and inspection tasks. The ratings by the test persons did not agree with the ratings by experts of the workload involved in the assigned tasks. A simultaneously used questionnaire assessing 4 aspects of mental strain (fatigue, tension, capability and motivation) did not provide any better agreement. The reasons are discussed.
Zeitschrift für Arbeitswissenschaft, 1990, Vol.44, No.1, p.24-29. Illus. 38 ref.


CIS 90-1700 Spencer G.T.
Radio headsets in the workplace
Les écouteurs radio en milieu de travail [in French]
The main health and safety concerns about using radio headsets in the workplace include distraction from warnings, inability to hear and hearing damage. As well as preventing a worker from hearing important messages and alarms, wearing a headset is particularly hazardous around moving equipment and automated devices. High sound levels also cause hearing damage and non-auditory health effects.
Canadian Centre for Occupational Health and Safety, 250 Main Street East, Hamilton, Ontario L8N 1H6, Canada, June 1989. 5p. Bibl.

CIS 90-670 Enander A.E.
Effects of thermal stress on human performance
Paper presented at the 3rd International Conference on Environmental Ergonomics (Helsinki, 8-12 Aug. 1988). Experimental evidence indicates that even relatively mild thermal stress may affect human performance. Tasks requiring manual dexterity and muscular strength are clearly impaired by cold exposure, while decrements in vigilance performance and endurance are well documented effects of heat stress. The considerable variation in results regarding the effects of thermal stress may, to some extent, be attributable to complex interactions between exposure conditions, task characteristics, and individual factors. In the present paper the relevance of some of the earlier research work on heat and cold stress is evaluated in the light of the practical and theoretical implications of more recent findings. Current work regarding the nature and extent of the effects of thermal stress on more complex performance is discussed. Attention is also focused on the significance of individual skill and training experience for performance under unfavourable conditions.
Scandinavian Journal of Work, Environment and Health, 1989, Vol.15, Supp.1, p.27-33. 63 ref.


CIS 90-2084 Landström U., Törnros J., Nilsson L., Morén B., Söderberg L.
Interactions between noise, temperature, wakefulness and performance analysed in a simulator study
Samband mellan vakenhetsmått och prestationsmått erhållna vid körsimulatorstudie avseende effekter av buller och temperatur [in Swedish]
Correlation analyses were carried out on the effects of noise and temperature on wakefulness and performance of subjects driving a simulator. Wakefulness was analysed through electroencephalographs and performance through recording of speed-holding, road-holding and braking. A positive correlation in time was observed between EEG, pulse and performance. The result is discussed with respect to the interaction between exposure to high levels of infrasound and fatigue and exposure to high levels of high frequency noise and alertness.
Arbetsmiljöinstitutet, Förlagstjänst, 171 84 Solna, Sweden, 1988. 18p. Illus. 6 ref.

CIS 89-1743 Sorkin R.D., Kantowitz B.H., Kantowitz S.C.
Likelihood alarm displays
In a likelihood alarm display (LAD), an automatic monitoring system computes the likelihood that an event will require operator action and it produces a signal for the operator. Operator performance on 2 simultaneous tasks was evaluated. The primary task was to use a joystick control to keep a cursor following a moving target on a CRT display screen. The secondary task was to monitor a numerical display and decide whether the data indicated a significant event. The secondary task was performed with no LAD, with a colour-coded visual alarm and with a synthetic speech alarm. The LADs improved performance on both primary and secondary tasks. Thus, LADs do not necessarily add to the operator's attentional load, but rather can improve the allocation of attention among tasks.
Human Factors, Aug. 1988, Vol.30, No.4, p.445-459. 25 ref.

CIS 88-1689 Floru R., Damongeot A., Di Renzo N.
Vigilance and adverse physical factors - 2. Combined effects of noise and vibration on vigilance during driving - Experimental investigation
Vigilance et nuisances physiques - 2. Effets de l'association du bruit et des vibrations sur la vigilance du conducteur - Etude expérimentale [in French]
2h of simulated driving was employed to study the combined effects of noise and vibration on performance and physiological arousal. Overall performance did not change significantly with experimental conditions, whereas the cerebral and autonomic arousal levels increased with noise and vibration, alone or in combination; performance deteriorated over time, and the arousal level decreased from the beginning to the end of the sessions. Since the same overall performance is observed at a higher arousal level during combined exposure to noise and vibration, there is a compensatory attentional effort for coping with the task under stress. The decrements in performance and physiological arousal over time indicate that this compensatory effort cannot be maintained throughout a long driving task under environmental stress.
Cahiers de notes documentaires - Sécurité et hygiène du travail, 1st Quarter 1988, No.130, Note No.1661-130-88, p.37-52. Illus. 30 ref.


CIS 89-1680 Löfstedt P., Landström U.
Noise, vibration and alertness during lorry driving
Buller, vibrationer och vakenhet under lastbilskörning [in Swedish]
Report describing measurements and analyses of noise, vibration and driver alertness during the operation of 2 different types of lorries. On the road, some lorries generated high and others low levels of low-frequency noise. No major differences were found between the 2 types with respect to dB(A) levels and levels of vibration. Drivers became more readily fatigued when driving lorries that generated a high level of low-frequency noise. The correlation between exposure to low-frequency noise and the risk of reduced alertness is discussed.
Arbetarskyddsstyrelsen, Publikationsservice, 171 84 Solna, Sweden, 1987. 49p. Illus. 24 ref.

CIS 89-1742 Warm J.S., Parasuraman R.
Vigilance: Basic and applied research
Articles in this issue deal with: mathematical functions that relate vigilance to the nature and duration of given tasks, to the nature and frequency of distracting events and to biological rhythms; different theoretical approaches to the study of vigilance; the significance of vigilance research in the real world.
Human Factors, Dec. 1987, Vol.29, No.6, p.623-743. Illus. Bibl.

CIS 88-1931 Zaneva N., Dinčeva E., Dazov E., Topalova M., Molova S.
Dynamics of neuropsychic capacity for work in clean rooms
Dinamika na nervno-psihičnata rabotosposobnost pri rabota v "čistite stai" [in Bulgarian]
The workload and the factors of the working environment (static microclimate, deficiency of negative air ions, work in windowless premises with artificial illumination, air locks impeding getting in and out of work-places, presence of potentially harmful chemicals) produce the following changes over a working day: monotonic decrease in the pulse rate, reduced muscular strength and endurance, lengthened reaction time, reduced adrenaline levels in urine. The changes suggest a considerable reduction of the tonic activation processes and the neuropsychic capacity of work.
Higiena i zdraveopazvane, 1987, Vol.30, No.6, p.15-21. Illus. 12 ref.

CIS 88-1734 Anderson R.M., Bremer D.A.
Sleep duration at home and sleepiness on the job in rotating twelve-hour shift workers
The relation between sleeping patterns at home and sleepiness ratings on the job was examined for 29 shift workers. The workers' 12h shift schedule was an eight-day cycle, with 2 day shifts followed by 2 night shifts and 96h off. The workers were categorised as early-onset or late-onset sleepers and as long or short sleepers, on the basis of their sleeping patterns on a non-working day. No significant differences were found between early-onset and late-onset sleepers in reported sleepiness on the job. The reported sleepiness on the job of short sleepers was significantly less than that of long sleepers on both day and night shifts. This difference was explained in terms of a hypothesised effect of long sleeping on circadian rhythms. Social factors appeared to explain the shorter sleeping periods of some workers.
Human Factors, Aug. 1987, Vol.29, No.4, p.477-481. 10 ref.

CIS 87-1516 Floru R., Cnockaert J.C., Damongeot A.
Vigilance and environmental stressors. Review of the literature
Vigilance et nuisances physiques - Synthèse bibliographique [in French]
This paper presents a synthesis of the literature on vigilance and the effects of environmental stressors on performance and physiological indices. The first part briefly reviews experimental research on vigilance and its physiological correlates. The second part mainly deals with the effects of noise, vibration and their association with behavioural and physiological responses during monitoring and driving tasks. In the third part, examples are used to illustrate activities where vigilance is important, and suggestions are made for improvement.
Cahiers de notes documentaires - Sécurité et hygiène du travail, 3rd quarter 1987, No.128, Note No.1635-128-87, p.331-355. Illus. 119 ref.

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