CR 198: Driver Fatigue: A Survey of Long Distance Heavy Vehicle Drivers in Australia (2001)
This is the report of a second national survey of long distance road transport drivers regarding fatigue and its effects on driving. This report examines the extent of changes in awareness and experiences of fatigue since the first survey, undertaken in 1991. The recent survey involved 1007 long distance road transport drivers from all mainland states of Australia. Two methods were used to collect information, a self-administered questionnaire and an interview, and around half of the responses were collected by each method. As the results from the two methods were quite similar and to increase the sample size for the study, the results from the two methods were combined.
The overall results showed that drivers reported fatigue less often than they had in the previous survey. In addition, only a small percentage of drivers in both surveys reported that fatigue was more than a minor problem for them, although many more felt that it was a significant problem for the industry. On the other hand, drivers reported that fatigue occurred considerably earlier than they had reported in the first survey. Most drivers in the current study reported that they experienced fatigue in the first 10 hours of starting driving which is considerably earlier than the 14 hours found in the first survey and well-within the permitted working hours for long distance drivers.
One of the major findings of this project was that overall, the reported experiences of fatigue while driving were very similar for both surveys and was consistent with the known effects of fatigue. Drivers experienced fatigue most in the early hours of the morning and to a lesser extent in the early afternoon. Long driving hours, and problems with loading and unloading were cited by drivers in both surveys as factors that increased fatigue, although in the second survey drivers were more likely to specify that waiting to load and unload was the most significant factor. Drivers in both surveys reported that fatigue affected their driving by slowing their reactions, impairing their gear changing and steering and by making them drive too slowly. The types of strategies that drivers reported as helpful in managing fatigue were also similar between the two surveys. More permanent methods of fatigue management such as sleep, rest, caffeine-containing drinks and stay-awake drugs were reported as the strategies that are most effective in managing fatigue in both surveys, whereas more temporary strategies like taking a shower, stopping for a meal and CB radios were judged as less helpful.
Fewer drivers in the current survey reported using stay-awake drugs and a smaller proportion rated them as helpful. This suggests that drugs are being used less to manage fatigue than previously. This finding may be associated with the lower reporting of personal fatigue by drivers in the second survey. As fewer drivers felt fatigue while driving, fewer needed stay awake drugs to manage their trips.
The pattern of results casts some doubt on the validity of this conclusion, however. Evidence from the patterns of the drivers work-rest schedules indicates that for many long distance drivers, the length of trips has increased since the earlier survey. While the average hours worked per week was somewhat lower for the current survey compared to the earlier survey, the distribution of weekly working hours was very similar. A significant proportion of drivers had problems recalling their weekly hours so the quality of reporting was limited. In contrast, most drivers were able to report details of the last trip. These results showed that many drivers in the current survey did considerably longer trips both in terms of distance and duration, compared to the drivers in the earlier survey.
Most drivers did at least some driving in the midnight to dawn period and just over one in five reported working for more than 72 hours in the past week, which is longer than allowed by current working hours regulations. This pattern of longer trips may be a reason for the reports of fatigue occurring much earlier in the trip than reported in the earlier survey. Very long trips would have made it difficult for drivers to obtain sufficient rest and recovery after the trip and as a result they tended to experience fatigue much earlier in the subsequent trip than if they had been better rested when the next trip started.
Other characteristics of the drivers reported work-rest schedules were also likely to be incompatible with good fatigue management. Around three-quarters of drivers did some work in the midnight to dawn period in the last week and on the last trip. On average, these drivers reported doing just over four hours of work in the six hour period between midnight and dawn on the last trip which corresponded to around one-quarter of the total work hours of the last trip. Drivers reported an average of nearly 10 hours over this period in the past week although the information on activities in the past week was much less reliable. These results suggest that night work is a very common part of the work of long distance drivers. Night work is well recognised to increase fatigue because it is more difficult to maintain adequate performance levels when working at night, especially over the early morning hours and because night work commonly leads to sleep deprivation due to the problem of obtaining sufficient sleep during the day. This survey showed that drivers who worked in the midnight to dawn period, in particular, had less access to good quality sleep. Furthermore, the study showed significant positive relationships between fatigue and the length of work on the last trip and between fatigue and the amount of night hours on the last trip. Fatigue increased with the amount of overall work and the amount of night work that drivers did.
There was a considerably higher participation in the current survey of drivers for small companies and a lower participation by drivers for large companies but the participation of owner drivers and drivers for medium-sized companies was quite similar to the earlier survey. Nevertheless, there were relatively few major differences between the different types of employment in the long distance road transport industry in either survey. The major differences were that in both surveys owner drivers did much longer trips than drivers who worked for companies, and compared to company drivers, independent owner drivers did far more non driving work but they had more flexibility in scheduling their trips. Regardless, there were no differences in reported fatigue experiences between any of the employment groups.
This survey provides evidence of other fatigue-related pressures on drivers that are at least partly due to the type of driving they do. Around one in five drivers reported a dangerous event which was fatigue-related on their last trip such as nodding off, crossing lanes and near misses. Nearly half of the drivers reported that they have nodded off while driving in the last year. These findings may appear to be at odds with the crash statistics for heavy vehicles, but clearly these incidents do not all lead to crashes. It is widely acknowledged that crash statistics underestimate the role of fatigue in heavy vehicle crashes. The results signal, however the fact that fatigue-related incidents are a common feature for long distance truck drivers and, if the circumstances in which these near misses occur conspire against them, may lead directly or indirectly to a catastrophic crash.
The survey pointed out a number of other pressures on drivers that are likely to increase their fatigue. Around one-quarter of drivers reported breaking working hours regulations on every trip. This is similar to the findings of the previous survey. The most common reasons cited in this survey by drivers who frequently break working hours regulations were work, organisational and reward factors like the need to do enough trips to earn a living and to get in early to get the next load.
In support of the role of organisational and reward factors, the survey also showed pressures on drivers due to their systems of remuneration. Drivers who were paid in terms of the amount of work they did (paid by results systems including flat load and trip rates) reported fatigue more often than drivers who were paid in terms of the time they were working (e.g. hourly rates). These results suggest that one of the targets for improving fatigue management practices should be a reduction in the amount of results-based remuneration in order to introduce some limits on the contingency between the amount of long distance work and pay that are based on health and safety.
Pressures on drivers due to problems of loading and unloading were clear from a number of parts of the survey. Most drivers were required to load or unload at some stage in their trips, a job that in many cases took two to three hours to complete. It is not surprising then, that loading and unloading were reported most consistently as the most significant contributors to fatigue. In particular, the problem of having delays and having to queue to load and unload was one of the major factors reported by drivers. This suggests that a review the system of freight forwarding would play a part in reducing fatigue for long distance drivers.
Drivers were also asked about their views of company and government approaches to fatigue management. With respect to strategies that companies can use to minimise fatigue, the majority of drivers reported that companies should improve efficiency of loading and unloading, increase driver pay rates, ease tight schedules, allow more time for on-road sleep and prohibit drivers from loading and unloading. In contrast, drivers felt that companies should not use two-up or staged driving or minimise night driving. On strategies that government can use, nearly all of the drivers reported public education about heavy vehicles, better roads, increasing flexibility to complete trips to suit the driver and providing better offroad rest facilities as approaches that the government should use. Introducing shorter driving hours and clamping down and enforcing working hours regulations were seen as approaches that the government should not use.
Overall, this survey has demonstrated a great deal of similarity in the reporting of working conditions and fatigue experiences by long distance drivers between the two surveys. A few factors have shown an apparent improvement over the seven years between the surveys. In particular these include reductions in both the number of drivers reporting fatigue as a personal problem and in the percentage reporting using stay-awake drugs. On the other hand, the current survey has shown a number of factors that do not indicate improvement. These include the higher reporting by drivers in the current survey of doing very long trips and of fatigue occurring much earlier in the trip than in the previous survey. The survey has also suggested some areas where improvement could enhance fatigue management in the industry.
These include reducing the number of very long trips required by drivers, reducing the amount of night work, reducing the amount of payment by results, reducing the amount of loading and unloading by drivers and the need to wait for long periods to load and unload. The survey results suggest that these factors provide very likely targets for improving fatigue management practices in the long distance road transport industry. Together with the companion survey of company representatives on fatigue and fatigue management also conducted by this research team, this survey has updated and extended our knowledge of the nature of the problem of fatigue for the long distance road transport industry and of the approaches that are most likely to overcome the problem.
Download Complete Document: Fatig_Trans_6 [PDF: 2141 KB]
Type: Research and Analysis Report
Sub Type: Consultant Report
Author(s): A Williamson, S Sadural, A-M Feyer, R Friswell
ISBN: 0 642 54476 X
Topics: Fatigue, Heavy vehicle
Publication Date: 01/09/01