Information for Interest | Pilot Advisory Notes | Restricted Access
Impact on Wives and Families | Work and Sleep Patterns | Implications for Fatigue Management
The work practices of Marine Pilots: a review
Acknowledgments
The research team from the School of Human Movements Studies at the Queensland University of Technology wish to thank all those who have contributed to the development of this review. Specifically, the research team wish to acknowledge the following organisations and individuals.
Australian Maritime Safety Authority
- John Hall, Richard Fleck
Barrier Reef Pilot Advisory Group Members
- Captain David Richardson (Australian Reef Pilots)
- Captains Phillip Marsh and Dennis Parsons (Queensland Coastal Pilot Service)
- Captain Richard Swain (Hydro Pilots)
Pilotage Companies
- Australian Reef Pilots – Dugal McKellar
- Queensland Coastal Pilot Service – Iain Steverson
- Hydro Pilots – Captain Richard Swain
Definitions and Abbreviations
Acute Fatigue: refers specifically to fatigue experienced as a direct consequence of some undertaking; e.g. following exercise or intense mental concentration.
Alertness: optimal activated state of the brain. Without alertness there can be no attentiveness, and without attentiveness, performance is affected. Alertness is a dynamic state and may vary from second to second. When people are alert, they have a better awareness of what is happening around them and are able to think clearly and take action.
AMSA: Australian Maritime Safety Authority
Boredom: a subjective experience of tedium produced by the unchanging nature of minimal task and environmental demands, and usually accompanied by impairments in attention.
Chronic Fatigue: refers to the cumulation of fatigue. When the amount of rest achieved is unable to completely restore arousal, fatigue accumulates and manifests itself in the more severe form of chronic fatigue. This condition is associated with feelings of weariness and lethargy prior to, during and following activity and requires a prolonged period of rest in order to completely recover.
Circadian adjustment: involves phasic adjustment of the circadian rhythms so as to match an unconventional sleep-wake cycle. While partial adjustment has been reported in some studies, complete adaptation has not.
Circadian dissociation: disruption of the normal relationship between circadian rhythms and zeitgebers; as occurs in night workers who are required to work and sleep at times when they are least able to perform either activity.
Circadian Rhythms: cyclical variation of biological activities which recur approximately every 24 hours. Hormone secretion rates, arousal and performance exhibit circadian patterns. In humans, circadian rhythms are generally phased to maximise arousal and activity during the day and induce sleep at night. Circadian rhythms are not dependant upon dark and light as in conditions of constant darkness or light, cyclical variations are still exhibited.
Cortisol: hormone secreted by adrenal cortex during times of stress.
Cumulative Sleep Debt: refers to the chronic build up of sleep deprivation which occurs when successive periods of inadequate sleep are experienced.
Dept. of Transport and Comm. – MIIU: the Department of Transport and Communication – Marine Incident Investigation Unit
EEG: (electroencephalogram) a recording of the electrical activity of the brain
Entrainment: process of synchronisation of circadian rhythms with the 24 hour schedule evident in society. Entrainment is achieved by the presence of social and environmental time cues.
EOG: (electro-oculogram) an electroencephalographic tracing made while moving the eyes a constant distance between two fixation points.
Epinephrine: (also termed adrenaline) chief hormone secreted by the adrenal medulla which is associated with preparing the body for action (i.e. the flight or fight response). Some of its effects include increasing heart rate, respiratory rate and alertness. Closely associated with norepinephrine.
Fatigue: all encompassing term used to describe a variety of different experiences such as physical discomfort from overworking a group of muscles, difficulty concentrating, difficulty appreciating potentially important signals and problems staying awake. In the present context, fatigue is important if it potentially reduces efficiency, erodes the safety margin or otherwise impairs cognitive or physical performance.
GBRP: Great Barrier Reef Pilots
Insomnia: sleep disorder referring to the inability to fall asleep easily, or to remain asleep throughout the night.
Maximum Oxygen Consumption: assessment of the maximum amount of oxygen able to be taken up and used by the body during physical activity. It is used as an indicator of aerobic fitness, with higher levels of maximum oxygen consumption being associated with higher levels of fitness.
Microsleep: brief periods of no response or prolonged reaction times often evident in sleep deprived individuals.
Nap: a brief period of sleep less than 4 hours in duration. Normally taken in addition to a sustained block of sleep (i.e. 4 or more hours), however in some situations a person’s sleep pattern may consist of one or more naps taken at various times throughout the day instead of a sustained block of sleep.
Near Miss: an incident in which a vessel passes unacceptably close to another ship, structure or navigational aid, or where there is an unacceptable risk of grounding, or damage to the environment.
Norepinephrine: (also termed noradrenaline) hormone secreted by the adrenal medulla. Most of it actions are similar to those of epinephrine.
NRC: National Research Council
NTSB: National Transportation Safety Board
Partial Sleep Deprivation: when sleep length is significantly reduced below usual sleep duration. Even 1.5 to 2 hours of sleep loss can have adverse effects on mood and performance.
Psychophysiological State: the psychological and physiological state of the person.
Qld Transport: Queensland Department of Transport
SIRC: Seafarers International Research Centre
Sleep Debt: the difference between a person’s minimum sleep requirement needed to maintain appropriate levels of alertness and performance, and the actual amount of sleep obtained by the person. It is most frequently determined by calculating the difference between sleep duration at home when the person has no work commitments and sleep duration preceding or following work commitments.
Split Sleep: taking sleep in two or more non-continuous blocks throughout a 24 hour period.
States/BC OSTF: States/British Columbia Oil Spill Task Force
Strain: any change in the individual produced by a stressor.
Stress: the subjective experience of excessive demand on one’s resources and capabilities.
Stressor: a task, environmental or personal factor responsible for the experience of stress.
Total Sleep Loss: sustained wakefulness. A period of time extending beyond usual wakeful hours during which no sleep is attained.
TSB: Transportation Safety Board of Canada
Vigilance: watchfulness; the ability to monitor and respond to appropriate stimuli.
Watchkeeping: duty involving monitoring of the ship’s position and ensuring course adjustments are made as required. Watchkeeping is performed from the bridge of the ship.
Zeitgebers: (German: time givers) normal social and environmental time cues; e.g. the changing light conditions across any 24 hour period, variations in social activities and clocks.
Abstract
Marine pilots are a unique group of seafarers who possess high levels of local area knowledge, shiphandling skills and navigational experience. When on board vessels, the pilot’s role is to work with the bridge team to ensure a safe passage through the pilotage region/s is achieved. As pilotage work is largely dependent on shipping demands and tidal conditions, work schedules are highly irregular with duties performed across all hours of the day and night. Potential stress-related outcomes of irregular work patterns are primarily associated with disrupted circadian rhythms, compromised sleep and social and domestic problems. Additionally, the long working hours, work underload, commercial pressures and on board and environmental conditions associated with marine pilotage work tends to further increase the stress experienced by pilots. This in turn can lead to a sub-optimal psychophysiological state, which may manifest as increased fatigue, mood deterioration and performance decrements.
Specifically, pilots appear to be at risk of exhibiting fatigue induced performance decrements when tasks require high levels of vigilance, decision making, judgment, memory and/or attention. When the irregular work patterns and disrupted sleep experienced by marine pilots are viewed in combination with a number of recent findings, a highly undesirable picture emerges. For instance, it has been recognised that fatigue contributes to significantly more shipping accidents than previously thought. It has also been identified that the work and sleep patterns of an individual are important factors in fatigue-related accidents and that working through the circadian troughs in alertness is associated with a higher relative risk of accidents. Hence, given the enormous environmental, economic and personal costs associated with shipping accidents, identification of the potential fatigue aspects of the work patterns of marine pilots is crucial. Additionally, training and strategies to recognise and manage fatigue in marine pilots should include both individual pilots and pilot providers.