{"id":40359,"date":"2025-11-09T01:23:56","date_gmt":"2025-11-09T01:23:56","guid":{"rendered":"https:\/\/carsp.ca\/?p=40359"},"modified":"2025-11-13T02:11:32","modified_gmt":"2025-11-13T02:11:32","slug":"sleep-related-distraction-why-its-important-to-investigate-and-document-driver-fatigue-in-road-traffic-collisions","status":"publish","type":"post","link":"https:\/\/carsp.ca\/en\/news\/carsp-news\/sleep-related-distraction-why-its-important-to-investigate-and-document-driver-fatigue-in-road-traffic-collisions\/","title":{"rendered":"Sleep-related distraction: Why it\u2019s important to investigate and document driver fatigue in road traffic collisions"},"content":{"rendered":"<p style=\"text-align: center;\"><span style=\"font-weight: 400;\">Christina M. Rudin-Brown, Ph.D., CCPE<br \/>\n<\/span><span style=\"font-weight: 400;\">Human Factors North, Inc., Canada<\/span><\/p>\n<p><b>Bio<\/b><\/p>\n<p><span style=\"font-weight: 400;\">Dr. Missy (Christina) Rudin-Brown, CCPE, is a human factors specialist with Toronto-based Human Factors North, Inc. (HFN). She has over 25 years\u2019 experience in road and transportation safety research, investigation and policy analysis, having worked for over 10 years as a senior human factors investigator and manager with the Transportation Safety Board of Canada (TSB) and, before that, for 4 years as a senior research fellow in human factors at the Monash University Accident Research Centre (MUARC) in Melbourne (Australia). From 1999 to 2009, she conducted human factors research with Transport Canada\u2019s Road Safety Directorate, supporting the development of federal motor vehicle standards and regulations. Dr. Rudin-Brown has been a human factors expert witness in over 30 road safety and motor vehicle forensic collision cases since joining HFN in 2012. She has also published over 100 peer-reviewed publications in the transportation human factors area, including two co-edited books.<\/span><\/p>\n<p><b>Abstract<\/b><\/p>\n<p><span style=\"font-weight: 400;\">Sleep-related fatigue affects a person\u2019s susceptibility to distraction. This has obvious consequences in terms of road safety and traffic collisions. A fatigue investigation methodology developed and used previously in other modes of transport was applied as part of a forensic human factors assessment of a motor vehicle collision where driver distraction played a role. The investigation found that sleep-related fatigue and driver distraction were contributing factors. While many collisions are investigated primarily for the determination of fault, criminal activity, or negligence, the results from this investigation demonstrate the importance of identifying, investigating, and documenting the risk factors and consequences associated with fatigue and its management in the road traffic context. Adopting a systems approach to forensic human factors investigation that includes the investigation of sleep-related fatigue can help to capture those \u2013 otherwise missed \u2013 opportunities to improve our roads and make driving safer.<\/span><\/p>\n<p><b>Background<\/b><\/p>\n<p><span style=\"font-weight: 400;\">While a vehicle operator falling asleep at the controls is the most obvious symptom of fatigue in transportation, less extreme fatigue levels are reliably associated with performance impairments in, for example, attention, information processing, memory, and reaction time. An even less well-known effect of sleep-related fatigue is its ability to increase one\u2019s susceptibility to distraction. This has obvious consequences for road safety, considering what is known about the effects of distracted driving on collision risk; according to 2019 to 2023 data in Transport Canada's National Collision Database, distracted driving contributes to an estimated 20% of fatal motor vehicle collisions.<\/span><span style=\"font-weight: 400;\">1<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Compared to other industries, where work hours are generally predictable, fatigue in transportation is made more likely by challenges to the human body's circadian rhythm caused by shiftwork. Commercial drivers and shift workers often work long and irregular schedules \u2014 sometimes in challenging conditions \u2014 that are not always conducive to getting sufficient restorative sleep. Although shift scheduling practices and hours of service regulations are designed to improve safety and efficiency of operations and to minimize the risk of employee fatigue, there remains a need to better understand and identify fatigue risks in the traffic safety context. Investigating transportation collisions is one way to do this.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Investigating for fatigue using a systems approach can identify the factors that contribute to fatigue, determine when fatigue does (and does not) contribute to a collision, and document the findings. Investigating leads to safety improvements in the future by providing the opportunity for drivers and road safety interest-holders to learn from the experience of others.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">This article presents some of the literature on sleep-related fatigue and its little-known relationship with distraction. A fatigue investigation methodology, developed and used previously in other modes of transport, was applied as part of a forensic human factors assessment of a motor vehicle collision where driver distraction played a role.<\/span><span style=\"font-weight: 400;\">2<\/span><span style=\"font-weight: 400;\"> The importance of investigating and documenting the risk factors and consequences associated with fatigue and its management in the road traffic context is highlighted.<\/span><\/p>\n<p><b><i>The collision<\/i><\/b><\/p>\n<p><span style=\"font-weight: 400;\">A highway collision took place on a Saturday night in August at approximately 2:30 a.m. Weather was clear at the time and road conditions were dry. The driver of a sedan was travelling south on a divided highway in the middle of three southbound travel lanes. The speed limit was 100 km\/h. As the driver approached the location on the highway where a friend\u2019s vehicle was stopped with a flat tire, they pulled over as far as possible onto the shoulder and left lane and stopped, activating the vehicle\u2019s flashing hazard lights and brake lights. A portion of the stopped vehicle remained in the travel lane.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">At around the same time, a young man was driving a company vehicle \u2013 a pick-up truck \u2013 also southbound, on the same highway, travelling in the left-most travel lane. He was on his way home after working a 16-hour shift as a construction apprentice. As his vehicle approached the area where the sedan was stopped, he was looking inside his vehicle, down and towards the right, adjusting the volume on his personal device. He reported not looking forward for \u201cabout 2 seconds\u201d. His truck was travelling between 106 and 111 km\/h and he did not see the sedan in his travel lane. The pick-up struck the rear of the sedan at 106 km\/h. Both vehicles came to rest in the left lane over 60 metres south of the point of impact. The sedan driver was seriously injured. The pick-up truck driver was charged by police for speeding.<\/span><\/p>\n<p><b>Sleep-related fatigue\u00a0<\/b><\/p>\n<p><span style=\"font-weight: 400;\">Sleep is a fundamental biological need. Normal, healthy adults need between 7 and 9 hours of sleep every 24 hours to feel well-rested and to be able to maintain vigilance throughout the day; anything less can result in fatigue.<\/span><span style=\"font-weight: 400;\">3<\/span><span style=\"font-weight: 400;\"> Because it is biological in nature, sleep-related fatigue cannot be prevented by, for example, characteristics of personality, intelligence, education, training, skill, or conscious motivation. While experiencing fatigue is a normal physiological and behavioural state, for drivers, experiencing fatigue while operating a vehicle can be catastrophic.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Less extreme levels of fatigue are reliably and significantly associated with performance impairments in cognitive functioning, including slowed reaction time,<\/span><span style=\"font-weight: 400;\">4<\/span><span style=\"font-weight: 400;\"> amongst others. At the extreme fatigue end, a person has difficulty maintaining wakefulness and, without being kept active and aroused, readily falls asleep.\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Performance decrements associated with fatigue are significant risk factors and predictors of occupational accidents and injuries, including motor vehicle accidents.<\/span><span style=\"font-weight: 400;\">5<\/span><span style=\"font-weight: 400;\"> An analysis of driving data collected under naturalistic conditions that used measurements of drivers\u2019 eye closure to identify drowsy driving found that drowsiness was involved in 8.8%\u20139.5% of all crashes examined and 10.6%\u201310.8% of crashes that resulted in significant property damage, airbag deployment, or injury.<\/span><span style=\"font-weight: 400;\">6<\/span><span style=\"font-weight: 400;\"> Crashes that occurred in darkness were more than three times as likely to involve drowsiness as those that occurred during daylight.<\/span><span style=\"font-weight: 400;\">6<\/span><span style=\"font-weight: 400;\">\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Shift scheduling practices can create conditions that increase the risk of employee fatigue. For example, shifts that are too long limit an individual\u2019s opportunities for sleep because they do not allow sufficient time to commute, or for personal activities like eating and hygiene \/ grooming.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Being awake for longer is also associated with greater pressure for sleep and, therefore, greater fatigue, especially at night.<\/span><span style=\"font-weight: 400;\">7<\/span><span style=\"font-weight: 400;\"> Research on the effects of fatigue <\/span><i><span style=\"font-weight: 400;\">vs.<\/span><\/i><span style=\"font-weight: 400;\"> alcohol on cognitive psychomotor performance found that 17 hours of wakefulness produced impairments in psychomotor functioning on a computer test of hand-eye coordination and reaction time that were equivalent to a blood alcohol concentration (BAC) of 0.05%.<\/span><span style=\"font-weight: 400;\">8<\/span><span style=\"font-weight: 400;\"> This is the proscribed level of alcohol intoxication for drivers in many countries, and is subject to administrative penalties such as immediate roadside license suspensions and vehicle impoundment in Canada. Twenty-four hours of sustained wakefulness resulted in cognitive psychomotor performance at a level equivalent to the performance deficit observed at a BAC of roughly 0.10%. (A BAC of 0.08% is the criminal driving limit in all Canadian provinces and territories.)<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Shift timing during the 24-hour circadian cycle also contributes to fatigue. In terms of sleep, day hours are not biologically equivalent to night hours. Many years of evolution have anchored human biology with sleep occurring during night hours and wakefulness within day hours. This means that the biological drive for sleep during the night hours is much stronger than during the day hours.<\/span><span style=\"font-weight: 400;\">9<\/span><span style=\"font-weight: 400;\"> It also means that fatigue can result from fewer hours of continuous wakefulness if these hours occur at night rather than during the day, even for regular night workers. Night shifts (those that include at least 3 hours of work between the hours of 11:00 p.m. and 06:00 a.m.) are the most significant single factor predicting severe sleepiness, leading to 6 to 14 times higher risk for \u201csevere sleepiness\u201d than day shifts.<\/span><span style=\"font-weight: 400;\">10<\/span><span style=\"font-weight: 400;\"> Therefore, safety is more likely to be compromised during night shifts than day shifts, particularly where night work is coupled with extended hours or overtime.<\/span><span style=\"font-weight: 400;\">11<\/span><\/p>\n<p><b>Driver distraction<\/b><\/p>\n<p><span style=\"font-weight: 400;\">Drivers spend about 80%-90% of their time driving looking ahead at the roadway and roadside, using eye fixations in the forward field.<\/span><span style=\"font-weight: 400;\">12<\/span><span style=\"font-weight: 400;\"> While they can switch their attention rapidly from one information source to another, humans can attend well to only one information source at a time.<\/span><span style=\"font-weight: 400;\">13<\/span><span style=\"font-weight: 400;\"> Therefore, a driver\u2019s attention can be compromised when they are distracted, which is defined as \u201ca diversion of attention away from activities critical for safe driving towards a competing activity\u201d.<\/span><span style=\"font-weight: 400;\">14<\/span><span style=\"font-weight: 400;\">\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Visual distraction occurs when a driver looks away from the road scene and instead focuses visual attention on another target, such as a handheld device.<\/span><span style=\"font-weight: 400;\">15<\/span><span style=\"font-weight: 400;\"> Cognitive distraction occurs when a driver\u2019s attention is withdrawn from the processing of information necessary for the safe operation of a motor vehicle and applied to a non-driving related activity.<\/span><span style=\"font-weight: 400;\">16<\/span><span style=\"font-weight: 400;\"> Manual distraction occurs when a driver takes one or both hands off the steering wheel to manipulate a control, device, or other non-driving-related item. All types of distraction, which can co-occur, slow driver reaction time and increase the likelihood that a driver will miss critical visual stimuli in the visual field and roadway ahead. The visual and manual distraction associated with handheld use of cellphones or other devices is why it is illegal in most jurisdictions to use handheld devices while driving.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">It is recognized that driver eye glances away from the forward visual scene are significantly associated with crashes and near-crash events. Research conducted under \u201cnaturalistic\u201d conditions, where everyday drivers operate their own vehicles while a range of video and vehicle performance data is recorded and later analyzed, has consistently found that driver eye glances away from the forward visual scene are significantly associated with crashes and near-crash events.<\/span><span style=\"font-weight: 400;\">17-18<\/span><span style=\"font-weight: 400;\"> More specifically, in-vehicle tasks that require glances totaling more than 2 seconds increase near-crash \/ crash risk by at least two times.<\/span><span style=\"font-weight: 400;\">17<\/span><span style=\"font-weight: 400;\"> Activities that require a driver to handle and look at a device result in the driver looking away from the road, and lead to impaired vehicle control and increased missed events.<\/span><span style=\"font-weight: 400;\">18<\/span><span style=\"font-weight: 400;\"> One of the largest naturalistic driving studies, the Second Strategic Highway Research Program 2 (SHRP2), found that 68% of the crashes that occurred involved some form of observable distraction.<\/span><span style=\"font-weight: 400;\">19<\/span><\/p>\n<p><em><b>Gaze eccentricity<\/b><\/em><\/p>\n<p><span style=\"font-weight: 400;\">Location of a control or device within a vehicle will affect how much, and for how long, a driver looks at it. Because they require central (foveal) vision, driver glances towards in-vehicle locations that are farther away from the forward line of sight are associated with poorer detection of target objects (missed targets) in front of the vehicle and slower reaction times to identify forward-located targets.<\/span><span style=\"font-weight: 400;\">20<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Driver survey studies<\/span><span style=\"font-weight: 400;\">21-23<\/span><span style=\"font-weight: 400;\"> have found that, among young drivers, music-related activities (e.g., playing and changing music on a smartphone) are the most common mobile phone activities undertaken when driving. Music search and selection tasks using kinetic interfaces like the ones used in smartphones increase the amount of time that drivers spend with their eyes off the roadway.<\/span><span style=\"font-weight: 400;\">24<\/span><\/p>\n<p><span style=\"font-weight: 400;\">In 2013, the United States introduced driver distraction guidelines<\/span><span style=\"font-weight: 400;\">25<\/span><span style=\"font-weight: 400;\"> for North American automobile manufacturers, to limit and reduce the potential for distraction from in-vehicle devices and controls. These guidelines recommended that glances to a device should require a maximum downward viewing angle of 30 degrees from the average driver\u2019s seated eye position to the geometric centre of the display. In 2019, Transport Canada also published guidelines to limit distraction from visual displays in vehicles, recommending that visual displays should not interfere with the driver's view of the road or any of the existing controls and displays and should be positioned in the forward view as close as possible to road centre, in line with the driver's forward view without obstruction.<\/span><span style=\"font-weight: 400;\">28<\/span><span style=\"font-weight: 400;\">\u00a0<\/span><\/p>\n<p><b>Sleep-related distraction<\/b><\/p>\n<p><span style=\"font-weight: 400;\">An interesting and less well-known aspect of fatigue is its relationship with distraction. Regardless of its causes, sleep disruption leads to fatigue and increases one\u2019s propensity to be distracted. A laboratory study looking at the relationship between fatigue and distraction demonstrated that, when the sleep of normal, healthy university students on the night before testing was restricted to only five hours, their performance on a proven, monotonous reaction time test \u2013 the psychomotor vigilance test (PVT) \u2013 deteriorated.<\/span><span style=\"font-weight: 400;\">26<\/span><span style=\"font-weight: 400;\"> In that study, 16 healthy young adults (8 men, 8 women) attended a laboratory in the afternoon on two occasions: once after their sleep was restricted to five hours, and another after they had a normal night\u2019s sleep. Participants underwent 30-minute PVT sessions in a sound-dampened cubicle both with, and without, an attractive distraction task \u2013 a popular television program playing on a nearby television. The television was located in the participant\u2019s visual periphery, 90\u00b0 away from the PVT monitor. Although they were instructed to ignore the television (whether it was turned on or off) and attend fully to the PVT, when they were sleep-deprived, participants made significantly more (almost six times as many) head turns toward the television and demonstrated significantly more (about 5 times as many) PVT \u201clapses\u201d (reaction times of longer than 500 milliseconds) than when they were fully rested. The distractive effect of fatigue was so strong that, even when participants were sleep-deprived but the television was turned <\/span><i><span style=\"font-weight: 400;\">off<\/span><\/i><span style=\"font-weight: 400;\"> during the \u201cno distraction\u201d condition, both an increase in head turns and in lapses occurred. The study authors interpreted this finding as showing that, \u201ceven in nondistractive environments, sleepy people will seek distraction, possibly in an attempt to overcome sleepiness or boredom\u201d.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">A more recent study explored how lack of sleep can affect one\u2019s \u201cdistractedness\u201d and found that people whose sleep was restricted were less able to recover from distractions than were people who were well-rested.<\/span><span style=\"font-weight: 400;\">27<\/span><span style=\"font-weight: 400;\"> In that study, over 200 people were assessed in a sleep lab. Between 10:00 p.m. and midnight, they worked individually on a procedural task that required several steps to complete. While they were working, participants were periodically interrupted. These repeated distractions meant that they had to reengage each time with where they were in the sequence of task steps. Afterwards, half of the participants spent the night at home and slept normally; the others stayed at the sleep lab and did not sleep at all. The participants were assessed on the same procedural task the next morning. Fifteen percent of the sleep-deprived participants were unable to complete the task compared to only one percent of the rested group. Those who were sleep-deprived but were able to complete the task made significantly more errors than those who were well-rested. The authors concluded that sleep-deprived individuals should not perform procedural tasks that are associated with \u201cinterruptions and costly errors\u201d or, if they must, they should perform such tasks only for short periods.<\/span><\/p>\n<p><b><i>Fatigue - Analysis<\/i><\/b><\/p>\n<p><span style=\"font-weight: 400;\">Due to the relationship between distraction and fatigue, and because the pick-up truck driver had been working many shifts before and was in the process of travelling home after a work shift at the time of the crash, a fatigue analysis for the pick-up driver in the collision described above was carried out. The analysis examined six known risk factors for sleep-related fatigue: 1) acute sleep disruptions; 2) chronic sleep disruptions; 3) continual wakefulness; 4) circadian rhythm effects; 5) sleep disorders; and 6) medical conditions. Hours of work and rest were plotted, as was commuting time, with 30 minutes of \u201cpersonal time\u201d applied at the start and end of each workday. Personal cellphone records were used to estimate sleep and wake times. On the pick-up driver\u2019s days off, and where cell phone records were not clear, a sleep time of 8 hours was assumed since he normally had restricted opportunities for sleep due to many back-to-back work shifts and because he had reported that \u201cit was tiring working a lot of shifts\u201d.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">An acute sleep disruption is understood to be a reduction in the quantity or quality of sleep occurring within the prior three days. On the night before the collision, the pick-up truck driver had a maximum opportunity for sleep of seven hours. The night before that, he had an opportunity to get only 5 hours of sleep. The night before that, he had a sleep opportunity of only 6 hours. This is less than the recommended 7 to 9 hours of sleep per 24 hours for adults.<\/span><span style=\"font-weight: 400;\">3<\/span><\/p>\n<p><span style=\"font-weight: 400;\">On both days leading to the crash, the pick-up driver had worked 16-hour shifts that began at 10:30 a.m. and ended at approximately 02:30 a.m. Assuming a wake-up time of 09:30 a.m. on the day of the collision would allow him half an hour to shower and eat, and half an hour to commute the approximately 23-minute drive to his place of work that day, the pick-up driver would have been awake for at least approximately 17 hours at the time of the crash (at 02:40 a.m.). This duration is associated with decrements in cognitive psychomotor functioning equivalent to those seen with a BAC of 0.05%.<\/span><span style=\"font-weight: 400;\">8<\/span><span style=\"font-weight: 400;\"> The timing of driving during the nighttime circadian trough (between approximately 10:30 p.m. and 04:30 a.m.) also increased the influence of the extended period of wakefulness on fatigue.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Chronic sleep disruption occurs where sleep quantity or quality disruptions are sustained for periods longer than three consecutive days. In the 20 days prior to the collision, the pick-up driver had a period of only two days (and two nights), when he did not work. His average total nightly sleep duration was only 6 hours, suggesting a chronic sleep disruption that would have placed him at an elevated risk of performance impairments associated with fatigue during that time.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The pick-up driver\u2019s work timesheets showed that he had worked many shifts on 18 of the 20 days before the collision, with only 2 days off and 3 days (of 17) where he worked 10 hours or less. On the other 14 days he worked 16-hour shifts. The sleep-wake history revealed that, at the time of the crash, and even if he had taken every possible opportunity to sleep in the preceding 5-day work period, the truck driver was at an increased risk for fatigue due to three risk factors: acute and chronic sleep disruption, and continual wakefulness.\u00a0<\/span><\/p>\n<p><b><i>Distraction - Analysis<\/i><\/b><\/p>\n<p><span style=\"font-weight: 400;\">Based on where in the vehicle the pick-up driver had been looking towards his handheld device, the downward viewing angle (from horizontal) to the device would likely have been greater than the recommended maximum downward angle of 30 degrees, requiring the driver\u2019s view (gaze eccentricity) to be away from the forward roadway and would be expected to result in poorer detection of, and longer reaction time to, hazards in the roadway ahead. This was confirmed by the driver\u2019s report that he had been looking towards his device \u201cfor about two seconds\u201d and did not detect the stopped vehicle in the roadway ahead until the airbags in his vehicle deployed.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">As a requirement for use of a company vehicle, the pick-up driver had signed a vehicle use agreement with his employer. The agreement stipulated that handheld cellphone use while the vehicle was in motion was prohibited.<\/span><\/p>\n<p><i><span style=\"font-weight: 400;\">Company safety program for fatigue, distraction<\/span><\/i><\/p>\n<p><span style=\"font-weight: 400;\">An employer has a responsibility to ensure a safe work environment for employees. For employers that provide employees with company vehicles, that includes road and vehicle safety elements, both to protect the employees and the travelling public. Fatigue and distraction are known road safety risks, and employers are responsible for managing and preventing the risks through their shift scheduling practices, vehicle oversight, employee safety and education programs, and incident reporting and investigation.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">A company\u2019s role in managing fatigue in its employees involves educating staff at all levels on the causes of and mitigations for fatigue, defining appropriate policies and procedures with respect to fatigue management, ensuring a working environment that minimizes fatigue as much as practicable, and striving for continual improvement in reducing fatigue by incident reporting and investigation. An employee\u2019s contribution to preventing fatigue includes applying knowledge of the effects of fatigue to take all reasonable steps to report for work well-rested, making effective use of fatigue countermeasures, recognizing the signs of fatigue in themselves and in co-workers, and taking action to ensure that fatigue arising from activities inside or outside of work does not lead to performance issues when working.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">At the time of the crash, the pick-up driver\u2019s employer had a company safety plan, which included a 1-page \u2018vehicle safety\u2019 section. The company also had a generic road safety program for\u00a0employees who commuted to and from work or who drove <\/span><i><span style=\"font-weight: 400;\">for <\/span><\/i><span style=\"font-weight: 400;\">work. The program was intended to prevent or mitigate the potential effects of various road safety risks, and included training (in-class, presentation, video), a manual, and a vehicle use \/ device use agreement to limit driver distraction.<\/span><\/p>\n<p><b>Discussion<\/b><\/p>\n<p><span style=\"font-weight: 400;\">The pick-up truck driver was experiencing sleep-related fatigue and was distracted in the seconds leading up to the collision, which, when considered in the context of the high speed at which the vehicle was travelling and the location away from the forward roadway towards where the pick-up driver was looking, prevented him from detecting and responding to the stopped sedan in time to avoid the impact. The fatigue analysis showed that, because he had been working a very challenging work schedule in the weeks preceding the collision that did not allow adequate time to obtain sufficient restorative sleep, and because he had been awake and working for at least about 17 hours at the time of the accident and during early morning hours, the pick-up driver was at high risk of performance impairments from fatigue, including slowed reaction time and an increased risk of becoming distracted.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Regardless of its causes, sleep disruption leads to fatigue and increases one\u2019s propensity to be distracted. The distractive effect of fatigue is so strong that, even when there are no distracting secondary tasks readily available, sleepy people tend to seek distraction, possibly in an attempt to overcome sleepiness or boredom.\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Although work and rest time of shift workers (like the pick-up driver) are not subject to professional drivers\u2019 hours of service regulations, there are legal considerations regarding an employer\u2019s responsibility when assigning work and a company vehicle. Informing drivers about company driving policies around device use and how to manage fatigue is important. With regards to managing the potential safety consequences of fatigue, although the pick-up driver\u2019s employer was aware of the number of shifts that he had been working in the weeks prior and of the number of hours that he worked on the day of the crash, they did not flag the potential for fatigue, nor did they investigate the collision to determine if fatigue played a role.<\/span><\/p>\n<p><b>Conclusion<\/b><\/p>\n<p><span style=\"font-weight: 400;\">Fatigue and distraction are known road safety risks, and the investigation of this collision concluded that both factors contributed in this case. While many road collisions are not investigated or are investigated primarily for the determination of fault, criminal activity, or negligence, there remains significant untapped benefit that could be gained if the investigation of road crashes were to be expanded in terms of breadth <\/span><i><span style=\"font-weight: 400;\">and <\/span><\/i><span style=\"font-weight: 400;\">depth. The importance of identifying, investigating, and documenting the risk factors and consequences associated with fatigue and its management in the road traffic context is clear. Adopting a systems approach to forensic human factors investigation that includes the investigation of sleep-related fatigue will help to capture those \u2013 otherwise missed \u2013 opportunities to improve our roads and make driving safer.<\/span><\/p>\n<p><b>References<\/b><\/p>\n<ol>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Transport Canada. Canadian Motor Vehicle Traffic Collision Statistics: 2023. Catalogue No. T45-3E-PDF. 2025. Available at: <\/span><a href=\"https:\/\/tc.canada.ca\/en\/road-transportation\/statistics-data\/canadian-motor-vehicle-traffic-collision-statistics\/2023\/canadian-motor-vehicle-traffic-collision-statistics-2023\"><span style=\"font-weight: 400;\">https:\/\/tc.canada.ca\/en\/road-transportation\/statistics-data\/canadian-motor-vehicle-traffic-collision-statistics\/2023\/canadian-motor-vehicle-traffic-collision-statistics-2023<\/span><\/a><span style=\"font-weight: 400;\">.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Rudin-Brown CM, <\/span><span style=\"font-weight: 400;\">Rosberg A.\u00a0Applying principles of fatigue science to accident investigation: Transportation Safety Board of Canada (TSB) fatigue investigation methodology.\u00a0Chronobiology International. 2021;\u00a038(2):296-300.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Hirshkowitz M, Whiton K, Albert SM, et al. National Sleep Foundation\u2019s sleep time duration recommendations: methodology and results summary. Sleep Health. 2015; 1:40-43.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Van Den Berg J, Neely G. Performance on a simple reaction time task while sleep deprived. Perceptual and Motor Skills. 2006; 102(2):589-599.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Dawson D, Chapman J, Thomas M. Fatigue-proofing: a new approach to reducing fatigue-related risk using the principles of error management. Sleep Medicine Reviews. 2011; 16(2):167-175.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Owens JM, Dingus TA, Guo F, Fang Y, Perez M, McClafferty J, Tefft BC. Prevalence of Drowsy Driving Crashes: Estimates from a Large-Scale Naturalistic Driving Study (Research Brief). 2018; Washington, D.C.: AAA Foundation for Traffic Safety.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Van Dongen HPA, Belenky G. Individual differences in vulnerability to sleep loss in the work environment. Industrial Health. 2009; 47:518-526.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Dawson D, Reid K. Fatigue, alcohol and performance impairment. Nature - International Journal of Science. 1997; 388(6639):235.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">\u00c5kerstedt T, Nordin M, Alfredsson L, Westerholm P, Kecklund G. Sleep and sleepiness: an impact of entering or leaving shiftwork \u2013 a prospective study. Chronobiology International. 2010; 27(5):987-996.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">H\u00e4rm\u00e4 M, Sallinen M, Ranta R, Mutanen P, M\u00fcller K. The effect of an irregular shift system on sleepiness at work in train drivers and railway traffic controllers. Journal of Sleep Research. 2011; 11:141-151.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Spurgeon A, Harrington JM, Cooper CL. Health and safety problems associated with long working hours: a review of the current position. Occupational and Environmental Medicine. 1997; 54(6):367-375.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Krauss D, Tavassoli A, Olson P. Driver eye movements and visual attention. Chapter 4 in: Krauss D, editor. Forensic aspects of driver perception and response, 4th Edition. Tucson: Lawyers &amp; Judges, 2015. P. 47-56.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Kantowitz B, Sorkin RD. Human factors: Understanding people-system relationships. New York: John Wiley and Sons; 1983.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Lee JD, Young KL, Regan MA. Defining driver distraction. In: Regan MA, Lee JD, Young KL, editors. Driver distraction: Theory, effects, and mitigation. Boca Raton: CRC Press; 2009.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Young K, Regan M. Driver distraction: A review of the literature. In: Faulks IJ, Regan M, Stevenson M, Brown J, Porter A, Irwin JD, editors. Distracted driving. Sydney, NSW: Australasian College of Road Safety; 2007. p. 379-405.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Strayer DL, Cooper JM, Turrill J, Coleman J, Madeiros-Ward N, Biondi F. Measuring Cognitive Distraction in the Automobile. Washington, DC: AAA Foundation for Traffic Safety; 2013 [cited 2025 Oct 2]. Available from:\u00a0 <\/span><a href=\"https:\/\/aaafoundation.org\/wp-content\/uploads\/2018\/01\/MeasuringCognitiveDistractionsReport.pdf\"><span style=\"font-weight: 400;\">https:\/\/aaafoundation.org\/wp-content\/uploads\/2018\/01\/MeasuringCognitiveDistractionsReport.pdf<\/span><\/a><span style=\"font-weight: 400;\">\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Klauer SG, Dingus TA, Neale VL, Sudweeks JD, Ramsey DJ. The impact of driver inattention on near crash\/crash risk: An analysis using the 100-car naturalistic driver driving study data. Virginia Tech Transportation Institute, Blacksburg, VA; 2006.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Kircher K, Patten C, Ahlstr\u00f6m C. Mobile telephones and other communication devices and their impact on traffic safety \u2013 A review of the literature. VTI rapport 729A; 2011.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Dingus TA, Guo F, Lee S, Antin JF, Perez M, Buchanan-King M, Hankey J. Driver crash risk factors and prevalence evaluation using naturalistic driving data. Proceedings of the National Academies of Science. 2016; 113:2636-2641.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Burns PC, Andersson H, Ekfjorden A. Placing Visual Displays in Vehicles: Where should they go? In: Rothengatter T, Huguenin RD, editors. Traffic and Transport Psychology - Proceedings of the International Conference on Traffic and Transport Psychology (ICTTP) 2000, Berne, CH; 2004.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">George AM, Brown PM, Scholz B, Scott-Parker B, Rickwood D. \u201cI need to skip a song because it sucks\u201d: Exploring mobile phone use while driving among young adults. Transportation Research Part F: Traffic Psychology and Behaviour. 2018; 58:382-391.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Jannusch T, Shannon D, V\u00f6ller M, Murphy F, Mullins M. Smartphone use while driving: an investigation of young novice driver (YND) behaviour. Transportation Research Part F: Traffic Psychology and Behaviour. 2021; 77:209-220.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Zhu M, Rudisill TM, Rauscher KJ, Davidov DM, Feng J. Risk perceptions of cellphone use while driving: results from a Delphi survey. International Journal of Environmental Research and Public Health. 2018; 15(6):1074.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Young KL, Mitsopoulos-Rubens E, Rudin-Brown CM, Lenn\u00e9 MG. (2012). The effects of using a portable music player on simulated driving performance and task-sharing strategies. Applied Ergonomics. 2012; 43:738-746.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Visual-Manual NHTSA Driver Distraction Guidelines for In-Vehicle Electronic Devices. Federal Register Volume 78, number 81, April 26, 2013. Available at: <\/span><a href=\"http:\/\/www.gpo.gov\/fdsys\/pkg\/FR-2013-04-26\/pdf\/2013-09883.pdf\"><span style=\"font-weight: 400;\">http:\/\/www.gpo.gov\/fdsys\/pkg\/FR-2013-04-26\/pdf\/2013-09883.pdf<\/span><\/a><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Anderson C, Horne JA. Sleepiness enhances distraction during a monotonous task. Sleep. 2006; 29(4):573-576.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Stepan ME, Fenn KM, Altmann EM. Effects of sleep deprivation on procedural errors. Journal of Experimental Psychology: General. 2019; 148(10):1828\u20131833.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Transport Canada. Transport Canada Guidelines to Limit Distraction from Visual Displays in Vehicles. 2019. Available at: <\/span><a href=\"https:\/\/tc.canada.ca\/en\/road-transportation\/stay-safe-when-driving\/transport-canada-guidelines-limit-distraction-visual-displays-vehicles\"><span style=\"font-weight: 400;\">https:\/\/tc.canada.ca\/en\/road-transportation\/stay-safe-when-driving\/transport-canada-guidelines-limit-distraction-visual-displays-vehicles<\/span><\/a><span style=\"font-weight: 400;\">.\u00a0<\/span><\/li>\n<\/ol>","protected":false},"excerpt":{"rendered":"<p>Christina M. Rudin-Brown, Ph.D., CCPE Human Factors North, Inc., Canada Bio Dr. Missy (Christina) Rudin-Brown, CCPE, is a human factors specialist with Toronto-based Human Factors North, Inc. (HFN). She has over 25 years\u2019 experience in road and transportation safety research,&#8230;<\/p>\n","protected":false},"author":2944,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_kad_post_transparent":"default","_kad_post_title":"default","_kad_post_layout":"default","_kad_post_sidebar_id":"","_kad_post_content_style":"default","_kad_post_vertical_padding":"default","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"_kad_post_classname":"","footnotes":""},"categories":[6,451],"tags":[],"class_list":["post-40359","post","type-post","status-publish","format-standard","hentry","category-carsp-news","category-safety-network-newsletter-news"],"acf":[],"_links":{"self":[{"href":"https:\/\/carsp.ca\/en\/wp-json\/wp\/v2\/posts\/40359","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/carsp.ca\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/carsp.ca\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/carsp.ca\/en\/wp-json\/wp\/v2\/users\/2944"}],"replies":[{"embeddable":true,"href":"https:\/\/carsp.ca\/en\/wp-json\/wp\/v2\/comments?post=40359"}],"version-history":[{"count":2,"href":"https:\/\/carsp.ca\/en\/wp-json\/wp\/v2\/posts\/40359\/revisions"}],"predecessor-version":[{"id":40414,"href":"https:\/\/carsp.ca\/en\/wp-json\/wp\/v2\/posts\/40359\/revisions\/40414"}],"wp:attachment":[{"href":"https:\/\/carsp.ca\/en\/wp-json\/wp\/v2\/media?parent=40359"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/carsp.ca\/en\/wp-json\/wp\/v2\/categories?post=40359"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/carsp.ca\/en\/wp-json\/wp\/v2\/tags?post=40359"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}