An analysis of the work schedules of Great Barrier Reef pilots

Summary of Results

The analysis of the work schedules, which included 902 tours of duty and 4310 work assignments, provided a basic description of the work practices of Great Barrier Reef pilots based on ship and non-ship periods. Key measures analysed from the work schedule files included the characteristics of tours of duty, work assignments, shipping routes and work-related travel. The analysis of the files was retrospective in nature and covered the 18 month period from January 1, 1996 to June 30, 1997. Between company differences and changes across three 6 month periods were assessed. Unless otherwise stated all measures were based on 6 month periods.

The differences in operations between the three pilotage companies are reflected in the results of the analyses. Company C is a small, newly established company operating in a single pilotage region only; Companies A and B are larger, longer established companies operating on all three shipping routes in the region.

CHARACTERISTICS OF TOURS

During a tour of duty, pilots perform one or more work assignments and alternate between working at sea and living ashore. The number and duration of tours, duration of breaks between tours and percent of tour time spent on assignment may, singly or in combination have some effect on the fatigue status of marine pilots. Analysis of the tour characteristics revealed that:

Company C performed significantly shorter tours, had seemingly longer rest breaks and spent a greater percentage of tour time on work assignments, than either Companies A or B. These results reflect the small size and single operational region of Company C.
Company B personnel performed more tours than Company A.
Breaks between tours were on average approximately 20 days for Company A and 13 days for Company B.
Mean tour duration was approximately 18 days for Companies A and B and 3 days for Company C.
Percent of tour time spent on work assignments ranged from approximately 50% for Companies A and B to 70% for Company C.
Frequency distributions indicated that in both Companies A and B, there was a small group of pilots performing more tours, longer tours and experiencing shorter breaks between tours, than depicted by mean company figures.
Analysis across the three 6 month time periods revealed that the duration of tours increased during the second time period.

CHARACTERISTICS OF WORK ASSIGNMENTS

Work assignments involve a continuous period of time spent by pilots on board vessels. Each work assignment was clearly identifiable in work schedule files by date, time and location of embarkation and disembarkation points. As travel to and from ships was regarded as work, assignment duration was travel adjusted. Between work assignments pilots live ashore. Analysis of work assignment characteristics showed that:

Number of Work Assignments

Company B personnel performed significantly more work assignments per tour than pilots from either of the other companies.
The average number of work assignments performed by pilots from Companies A, B and C were 22, 29 and 7 respectively. These findings reflect a 31% greater workload for pilots from Company B compared with Company A.
Company B pilots performed approximately 51% more work than Company A pilots on the Inner Route.
Significantly fewer work assignments were performed by Company A personnel on Hydrographers Passage compared with the other two companies.
A similar number of work assignments were performed by Companies A and B on the Great North East Channel.
Frequency distributions for work assignment per tour and per pilot indicated that in some instances, substantially more work assignments were undertaken. Compared with average company figures, there were some situations when almost twice as many work assignments were performed. This distribution pattern also applied when the number of assignments performed on the Inner Route and Hydrographers Passage were assessed.
A significantly greater number of work assignments per tour, per pilot and on the Inner Route were undertaken during the second 6 month period. This temporal pattern was observed for all of the pilotage companies, thereby indicating an increase in overall work availability during this period.

Duration of Work Assignments

Average work assignment duration for Companies A, B and C was approximately 46, 41 and 14 hours respectively.
Frequency distributions showed that in both Companies A and B, there were a number of assignments which greatly exceeded average work assignment duration.
Compared with other groups of marine pilots, the duration of work assignments performed by Great Barrier Reef pilots were substantially longer.

Duration of Rest Breaks between Work Assignments

Company A pilots experienced longer breaks between work assignments compared with Company B.
Distribution curves for all companies were markedly skewed, thereby indicating that most consecutive work assignments were interspersed by 24 hours or more. However, there were a number of situations for Companies A and B when break duration was less than current minimum rest break regulations. This applied to all three shipping routes.
By calculating work to rest ratios for Great Barrier Reef pilots and long haul pilots from the United Kingdom, it was evident that rest periods relative to work periods were substantially shorter for Great Barrier Reef pilots.

Duration of Work Assignment at Night

Average duration of work assignments performed during the night for Companies A, B and C was approximately 25, 23 and 7 hours respectively. These figures represent approximately 50% of total assignment time for each of the companies.
The distribution curves displaying the percent of assignment time at night show that the majority of work assignments for Companies A and B involve between 40 - 60% of night work. That some work assignments performed by Company C involved almost total night work reflects the short transit time through Hydrographers Passage.
The amount of work performed at night did not vary significantly over time thereby suggesting regular night work is a common feature of Great Barrier Reef marine pilotage.

Starting times of work assignments and breaks

Starting times of Great Barrier Reef pilotage work assignments were fairly evenly distributed across the six 4 hour period making up the 24 hour cycle. This pattern was consistent for all companies and across time.
Starting times of breaks between work assignments also showed an even distribution across the six 4 hour period making up the 24 hour cycle. It would therefore appear that a high level of irregularity in the timing of work and rest breaks is present in Great Barrier Reef marine pilotage work. This finding is consistent with the available literature on other groups of marine pilots.
These findings suggest that work and sleep would frequently be asynchronous with normal circadian rhythms of the body.

Opportunity for optimal sleep during assignment breaks

Breaks between assignments for Company B provided fewer opportunities for uninterrupted sleep during optimal circadian periods (2200-0800 hours) than Company A’s breaks.
There were a number of occasions over the 18 month analysis period for all three companies when rest breaks between assignments failed to present pilots with any opportunity to achieve uninterrupted sleep during optimal periods.

CHARACTERISTICS OF SHIPPING ROUTES

The three main shipping routes transited by Great Barrier Reef pilots include Hydrographers Passage, the Inner Route and the Great North East Channel. Both Hydrographers and the Inner Route are areas of compulsory pilotage. When an analysis of the shipping routes was undertaken, it was identified that:

Inner Route assignments constitute ~ 70% of Great Barrier Reef pilotage work, Hydrographers Passage assignments, ~ 20% and Great North East Channel assignments, ~ 10%.
Inner Route assignments were significantly longer than assignments on either of the other two shipping routes.
Average transit time through Hydrographers Passage was shortest.
A higher percentage of night work was experienced on the Inner Route.
Starting times of assignments and breaks on the three routes were fairly evenly distributed across the 24 hour cycle.
Significantly more travel to and from ships was undertaken on the Great North East Channel.
The opportunity for uninterrupted sleep during optimal periods (2200-0800 hours) was significantly less during rest breaks prior to assignments on Hydrographers Passage.

CHARACTERISTICS OF TRAVEL

Great Barrier Reef pilots undertake a substantial amount of work-related travel. Given that travel may potentially impact on recovery periods and hence, influence the fatigue status of pilots, an assessment of the impact of travel was conducted.

The States/British Columbia Oil Spill Task Force has stated that travel to and from work and between work should be considered part of work hours (States/British Columbia Oil Spill Task Force, 1997). In consultation with Great Barrier Reef pilot advisory group members, it was decided that travel to and from embarkation and disembarkation grounds and travel between work assignments should constitute work. Accordingly, travel data was input into existing work schedules. No distinction between the mode of travel used (launch, helicopter, fixed wing aircraft) was made; only travel time was considered.

Travel significantly increased work assignment duration, decreased breaks between work assignments and increased the night time periods during work assignments.
Travel from all sources per tour for Companies A, B and C was approximately 12, 18 and 4 hours respectively. These figures represent significantly longer hours of travel for pilots from Company B.
The analyses of travel time to and from ships and between ports indicate that Company B personnel engage in more travel per tour than Company A.
Company C undertakes no travel between ports, given their single operational region.
Company B pilots incurred more travel to and from ships per work assignment.
On average, less than 10% of break times between ships were spent travelling; however, travel is most likely fragmented throughout the assignment break period, thereby reducing the recuperative value of recovery periods.
Over the 18 months, significantly more travel was undertaken during the second 6 month period. This result is consistent with previous findings indicating increased work availability during this period.

SUMMARY

A number of potential key indicators of fatigue were identified from the analysis of the work schedule files. For example, the irregularity of work assignments (ship time) and rest breaks (non-ship time), the substantial percentage of ship time undertaken at night, and the displacement of work and sleep from normal circadian cycles could, singly or in combination, impact on the fatigue status of pilots. It was also identified that work-related travel significantly increased work assignment duration, decreased the duration of breaks between assignments and increased the percentage of night work. Additionally, there was a distinct increase in work availability in all pilotage groups in the second time period (June-December, 1996). Hence, travel and work availability may exacerbate the effects of other potential fatigue factors.

To some degree the increased commercial pressures created by the privatisation of pilotage in the Great Barrier Reef region is reflected in the between company differences in work assignment characteristics; over the 18 month analysis period, Company B personnel performed greater workloads than Company A pilots. It was also recognised that there were some instances when personnel from both Companies A and B performed considerably more assignments and experienced shorter breaks than average company figures. Although extreme workloads were undertaken by only a small group of pilots, it is these situations which are of concern in the context of both acute and chronic fatigue development, performance decrements and risk of accident.

AREAS FOR CONSIDERATION

The analyses of the work schedule files strongly suggest that there is a high potential for fatigue among Great Barrier Reef pilots. The extensive analyses based only on ship and non-ship time revealed the presence of several factors previously identified in the literature as impacting on fatigue. These were:

irregular timing of work and rest periods across the 24 hour cycle;
long on-ship periods;
night work;
displaced work and sleep from usual circadian patterns;
increased workload due to work-related travel;
instances where considerably greater workloads and shorter rest breaks were experienced by pilots, compared with average company figures;
significant time period (July-December) increase in work availability; and
significant company differences in workload levels.
As indicated in previous communications analysis of the work schedule data provides only one source of information related to the fatigue aspects of the work of Great Barrier Reef pilots. The work schedule information is an extensive data set comprising 4310 records reported retrospectively to AMSA over an 18 month period. It was the only data available to the researchers but is a valuable resource, the analysis of which has provided some useful information which may be applied to the evaluation of the existing reporting and monitoring system and identification of areas worthy of consideration, and which may enhance current procedures.

At this stage the applicability of the results to any modification of scheduling guidelines is limited as the present reporting system provides no specific details regarding the nature of work and rest periods and their impact on fatigue and performance. Without this information it is difficult and irresponsible to suggest definitive strategies and changes to work scheduling practices. Satisfactory completion of the final stages of the project and the additional log book data should provide a more substantive basis for the recommendation of guidelines concerned with these work practices.

The findings from this phase of the project together with information from the research literature provide opportunities for AMSA together with the pilot advisory group and the research team to consider a number of broad areas which may lead to improvement in the present reporting and monitoring of work scheduling practices. To this end it is suggested that the results of this interim report be considered by AMSA and the Pilot Advisory Group with reference to the following areas:

The adequacy of the current system of reporting work/rest information;
The inclusion of additional information to enhance reporting and knowledge of potential fatigue indicators;
The design of more efficient reporting systems to provide a more pro-active/preventative approach to potential fatigue problems rather than the more reactive system currently operating;
The significance of travel time in the fatigue equation;
The monitoring of work/rest guidelines;
The development of a system which, (a) enables companies to allocate work to pilots which is consistent with the guidelines for rest breaks and (b) evens out the distribution of work and rest over the year and optimises the use of personnel during busy periods.


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