TSB fatigue-related findings, 1990–2018
The Transportation Safety Board of Canada (TSB) has identified fatigue as a causal or contributing factor or a source of risk in 91 investigations conducted up until October 2018. These investigations have included 29 occurrences in the railway industry, 28 in the marine sector, and 34 in aviation.
Table 1. Rail investigation reports
|R17D0123||Employee Fatality, CP||2017-11-08||Quebec||Findings as to causes and contributing factors—It is likely that the yard helper's fatigue contributed to the incorrect alignment of the 2WL/WL crossover switch.|
|R16W0242||Uncontrolled movement, collision and derailment, CP||2016-11-29||Saskatchewan||Finding as to risk—If train crew members remain on duty after an extended period of wakefulness, there is a risk that the performance of cognitive task could be adversely affected.|
|R16E0051||Main-track train collision, CN||2016-06-04||Alberta||Finding as to risk—If call times for train crew schedules cannot be reliably predicted, operating crew members may not be able to achieve sufficient restorative sleep, which can lead to accumulated sleep debts, increasing the risk of fatigue.|
|R16H0024||Collision between train and track unit, CP||2016-03-06||Ontario||Finding as to cause—At the time the decision was made to depart Kinogama Siding, the foreman's level of fatigue and its negative impact on performance had been influenced by a number of interacting factors, likely including the combined effects of 2 sleep disorders (which were each considered mild), the time of day during a circadian trough, and a demanding work schedule.
Finding as to risk—If maintenance-of-way employees who carry out safety-critical tasks are not subject to enhanced medical requirements, underlying medical conditions, including sleep disorders that affect the safety performance of employees, can go undetected, increasing the risk of accidents.
|R16C0012||Non-main-track derailment, CP||2016-02-18||Alberta||Finding as to cause—The locomotive engineer's working memory and vigilance were likely limited due to fatigue, contributing to the improper train handling.
Findings as to risk
|R15V0046||Movement exceeds limits of authority, CP||2015-03-11||British Columbia||Finding as to risk—During periods of reduced alertness (such as low circadian rhythm), there is an increased risk of inadvertent errors, such as the misrepresentation of communications with other railway employees.|
|R15V0003||Main-track derailment, CP||2015-01-13||British Columbia||Finding as to risk—If fatigue management principles and best practices are not considered or permitted by company policy, and are not used by all employees involved in operating or routing trains, including personnel at the Rail Traffic Control Centre, employees can be in a fatigued state when making critical safety decisions, increasing the risk of non-optimal decisions leading to accidents.|
|R14V0215||Main-track derailment, CN||2014-11-15||British Columbia||Finding as to cause—The crew members were fatigued at the time of the occurrence, as they had been experiencing circadian rhythm disruptions in the days prior. This state of fatigue probably affected their ability to recognize the significance of the wheel slip alarm and the earlier than expected HBD/HWD/DED announcement.
Finding as to risk—If shift start times are highly variable, train crew members may not be able to obtain good-quality sleep on a regular basis, resulting in fatigue during duty shifts, and increasing the risk of accidents.
|R12V0008||Collision between train and track unit, CN||2012-01-14||British Columbia||Finding as to cause—The foreman's diminished state of alertness and his focus on the south portion of the right-of-way likely contributed to the formulation of an erroneous mental model, resulting in him taking the south track.|
|R11D0075||Main-track derailment, CN||2011-09-24||Quebec||Finding as to risk—Crews that work variable, unpredictable schedules are exposed to an increased risk of diminished alertness associated with the desynchronization of their circadian rhythms.|
|R11E0063||Collision with tail-end of stationary unit on main-track, CN||2011-06-23||Alberta||Finding as to cause—The cognitive processes of the experienced and qualified train crew members were likely impeded by reduced alertness, leading to the inappropriate train control.
Other finding—Despite the availability of the Work/Rest Rules, work scheduling practices for train crews continue to be a challenge for employers and employees in the railway industry.
|R10T0213||Main-track derailment, CN||2010-10-01||Ontario||Finding as to cause—The locomotive engineer was insufficiently rested to be engaged in safety-critical tasks. His fatigued state was compounded by the challenge of operating an unfamiliar train during an unplanned braking event in undulating territory with a number of curves.
Finding as to risk—Given that it is left to employees to determine whether they are fit to work, when faced with loss of wage and/or potential company discipline, there is an increased risk that a fatigued employee will accept work, compromising safe train operation.
|R10Q0037||Main-track derailment, CN||2010-08-23||Quebec||Finding as to risk—Certain factors (e.g., concurrent tasks, darkness, reduced vigilance), whether alone or in combination, can reduce the inspector's ability to perform his work.|
|R10E0096||Switching assignment colliding with stationary cut of cars, CN||2010-08-18||Saskatchewan||Finding as to cause—A reduced level of alertness contributed to the foreman's actions, including his decision to bypass the requirement for visual point protection of the movement and his actions leading to misrouting assignment 602 into track VC-64.|
|R10Q0011||Main-track derailment, VIA Rail||2010-02-25||Quebec||Finding as to cause—The crew's planning and reaction to more complex issues was likely degraded due to fatigue.|
|R09W0259||Non-main-track collision with stationary train, CP||2009-12-19||Saskatchewan||Finding as to risk—Operating crews that work variable and unpredictable work schedules may be at increased risk of performance impairments due to fatigue.|
|R07E0129||Non-main-track collision with side of train entering siding, CN||2007-10-27||Alberta||Finding as to cause—Train 417's crew was insufficiently rested to be engaged in safety-critical tasks.
Finding as to risk—From time to time, fatigued train crews will feel compelled to report for work without adequate rest, creating the risk of an accident.
Other finding—Despite previously-acquired knowledge on fatigue, the countermeasures the railway had in place were ineffective.
|R07V0213||Non-main-track collision involving a Beltpack assignment and train, CN||2007-08-04||British Columbia||Finding as to risk—While both regulatory and company Work/Rest Rules address fatigue in the short term, regulatory requirements give inadequate consideration to the cumulative effects of working extended hours over the longer term because there are no specific limitations placed upon any employee who exceeds 64 hours of work in seven days.|
|R06W0079||Main-track derailment, CP||2006-05-22||Saskatchewan||Finding as to risk—The interpretation of the Work/Rest Rules for Railway Operating Employees that allows a trip, which routinely exceeds 12 hours, to be planned as two tours of duty creates a situation in which crews may routinely exceed the 12-hour maximum tour of duty and work up to 18 hours with little or no rest break. This increases the risk that crew performance will be adversely affected by fatigue.|
|R05C0082||Main-track derailment, CP||2005-05-27||Alberta||Finding as to cause—It is possible that fatigue played a role in the train handling errors, that is, the rapid changes in throttle and dynamic brake that were made in this instance.
Finding as to risk—The regulatory and industry framework for the management of risks related to fatigue may not adequately protect against the effects of fatigue that result from the work/rest cycle of train crews.
|R03W0169||Main-track derailment, CP||2003-10-19||Ontario||Findings as to risk
|R99E0023||Runaway, collision and derailment, CN||1999-01-31||Alberta||Finding as to risk—The rest/work cycle and sleep pattern of the crew, especially the conductor, were conducive to fatigue and a consequent risk of performance impairment.|
|R98V0183||Main-track collision, CN||1998-10-01||British Columbia||Findings as to cause
|R97C0147||Runaway and derailment, CP||1997-12-02||British Columbia||Finding—The performance of the locomotive engineer may have been affected by fatigue which would have impaired his ability to make critical operating decisions.|
|R96W0171||Collision with head-end of stationary train and derailment, CN||1996-07-02||Saskatchewan||Findings
Safety concern—The Board believes that implementation of initiatives such as CANALERT, coupled with a comprehensive hours of service rule, is necessary to alleviate the problem of fatigue in the railway operating environment. The Board is concerned that, although certain elements of CANALERT have been implemented, there has not been widespread application of the CANALERT concepts.
|R96Q0050||Collision with rear of stationary train, Quebec North Shore and Labrador Railway||1996-07-14||Quebec||Finding—The possibility that fatigue may have contributed to the locomotive engineer's decision not to comply with the governing signal indication cannot be ignored.|
|R95V0218||Collision between 2 trains, CP||1995-10-01||British Columbia||Finding—Both crew members of train 819 were impaired by fatigue as they approached the Stop Signal at Greely and operated their train past the signal and into train 996.|
|R95S0021||Collision with rear of stationary train, CN||1995-02-16||Ontario||Finding—It is probable that the locomotive engineer of train 272 succumbed to fatigue and experienced a sleep episode as his train was approaching Signal 44.|
|R94T0334||Collision with rear of stationary train, CN||1994-10-28||Ontario||Finding—Reduced alertness from disruption of the normal sleep cycle probably was a contributing factor in the inappropriately high speed just before the collision.|
Table 2. Marine investigation reports
|M17P0244||Bottom contact, Tug Ocean Monarch||2017-07-09||British Columbia||
Findings as to causes and contributing factors
Findings as to risk
|M16P0378||Grounding and sinking of articulated tug-barge Nathan E. Stewart and tank barge DBL 55||2016-10-13||British Columbia||Finding as to cause—The second mate, who was working alone on the bridge, was fatigued and fell asleep. As a result, he did not make the planned course alteration, and the articulated tug-barge struck and grounded on a reef.
Finding as to risk—If a 6-on, 6-off shift schedule is used without fatigue-mitigating measures, there is a risk that crew members will carry out their duties while impaired by fatigue.
|M15C0006||Grounding of self-discharging bulk carrier Atlantic Erie||2015-01-11||Quebec||Finding as to risk—If mariners, including the master, exceeded the regulated hours of work and are not properly rested, there is a risk of fatigue-related accidents.|
|M14C0219||Bottom contact of tanker Nanny||2014-10-14||Nunavut||Findings as to cause
Finding as to risk—If marine regulations do not require companies to develop comprehensive fatigue management plans, performance decrements may occur in those who occupy safety-critical positions, increasing the risk of incidents and accidents.
|M12L0147||Grounding of bulk carrier Tundra||2012-11-28||Quebec||Finding as to cause—Fatigue was a likely factor in the pilot's diminished situational awareness at a critical time when a course change was required.
Finding as to risk—Without training in fatigue awareness, there is a risk pilots may not be able to identify symptoms or signs related to sleep disorders, which are not detectable through a regular medical exam.
|M12F0011||Collision between fishing vessels Viking Storm and Maverick||2012-09-28||United States||Finding as to cause—It is highly likely that the cognitive abilities of the mate on the Viking Storm were reduced due to fatigue resulting from a combination of acute sleep loss, continuous wakefulness, and circadian rhythm timing.
Findings as to risk
|M12N0017||Striking of wharf by Passenger vessel Beaumont Hamel||2012-05-30||Newfoundland and Labrador||Finding as to risk—Fatigue-management plans that do not provide sufficient opportunity for restorative sleep increase the risk of reduced crew performance on a routine basis.|
|M11W0091||Striking of bridge by tug F.W. Wright and barge Empire 40||2011-06-28||British Columbia||Findings as to cause
|M09W0064||Collision between fishing research vessel Velero IV and fishing vessel Silver Challenger II||2009-04-08||British Columbia||Finding as to risk—Work/rest schedules that do not provide for sufficient restorative sleep are likely to lead to fatigue, performance degradation, and errors due to lack of attention, alertness, and vigilance.|
|M08C0024||Grounding of bulk carrier Algomarine||2008-05-28||Ontario||Finding as to cause—Lack of sleep contributed to the master's fatigue, which in turn likely affected his performance. Sleep disturbance could have been exacerbated by the negative side effects of quitting smoking and the use of a prescription drug.|
|M07L0158||Striking of passenger vessel Nordik Express||2007-08-16||Quebec||Finding as to risk—In the absence of a fatigue management plan, the probability of fatigue-induced errors increases, thereby increasing the risk to vessels, crew, passengers, and the environment.|
|M06F0024||Crew member of sail training vessel Picton Castle lost overboard||2006-12-08||Nova Scotia||Finding as to cause—The deckhand was likely affected by fatigue and a loss of alertness at the time of the occurrence.|
|M06N0014||Fire in cargo oil tank of shuttle tanker Kometik||2006-04-08||Newfoundland and Labrador||Finding as to cause—A crew member with a high workload of safety-sensitive duties worked while in a fatigued state, leading to insufficient oversight of the welding activities.
Finding as to risk—The vessel's shipboard safety manual did not identify fatigue or workload as risk factors and did not incorporate procedures to mitigate them.
|M06W0052||Striking and sinking of passenger and vehicle ferry Queen of the North||2006-03-22||British Columbia||Finding—The change from sleeping during the night to sleeping during the day, together with the restless sleep, likely increased the risk of QM1 being fatigued.|
|M05C0063||Grounding of bulk carrier Michipicoten||2005-10-28||Ontario||Finding as to cause—The master's work/rest schedule at the time of the occurrence did not adhere to well established regulatory requirements.
Finding as to risk—The regulatory requirements to help ensure masters and officers have enough rest were not incorporated in the company's written procedures.
Other finding—The master's schedule may have predisposed him to fatigue-related performance issues.
|M04L0099||Collision between pleasure craft Mondisy and container ship Canada Senator||2004-08-11||Quebec||Finding as to cause—It is likely that the unstructured watchkeeping system aboard the Mondisy led to a sleep debt that caused the co-worker to fall asleep while on duty at the helm.|
|M04L0092||Container ship Horizon||2004-07-24||Quebec||Finding as to cause—Fatigue may have been a factor in the pilot's decreased vigilance at a critical time.
Finding as to risk—Despite fatigue awareness training and contractual arrangements that set out adequate rest for pilots, fatigue continues to be a factor in occurrences.
|M02L0061||Bulk carrier Kent||2002-07-16||Quebec||Finding as to risk—In the 24 hours preceding the accident, the bosun only had four hours off duty, and his judgment, reaction time, and alertness would have been adversely affected by fatigue.|
|M02C0011||Tug-barge unit Progress/Pitts Carillon||2002-04-21||Ontario||Finding as to cause—The adopted work-rest schedule for the crew was not conducive to acquiring proper rest, and the crew's performance was likely affected by fatigue at the time of the occurrence.|
|M97W0197||Grounding of bulk carrier Raven Arrow||1997-09-24||British Columbia||Finding as to cause—The pilot did not fully appreciate the negative effects that an irregular work schedule and sleep debt can have on performance. The pilot was probably fatigued and there was no formalized education/training program in place regarding conditions conducive to fatigue and the impact of scheduling on fatigue.|
Passenger ferry Wolfe Islander III
|1996-05-29||Ontario||Finding—It is likely that master was suffering from fatigue, which may have adversely affected his judgement and performance.|
|M94W0066||Collision Fishing vessels Narvik and Island Joy||1994-08-21||British Columbia||Finding—The skipper/owner of the Island Joy fell asleep while alone on watch.|
|M94W0057||Fall overboard Bulk carrier Pacific Brilliance||1994-07-27||British Columbia||Finding—The shipyard personnel, including the victim, had been working for over 17 hours and they used an unsafe gangway to disembark from the vessel.|
|M94M0036||Collision Fishing vessel Lady Olive Marie, racing sailboat Coyote||1994-08-24||Nova Scotia||Finding—Due to fatigue, a proper lookout onboard the Coyote was not being maintained as required by the International Regulations for Preventing Collisions at Sea.|
|M93M0008||Small lobster vessel Stump Jumper||1993-11-30||Nova Scotia||Finding—The operator's performance was probably impaired by the cumulative effects of his diabetic condition and work-induced fatigue.|
|M93L0001||Bulk carrier Canadian Explorer||1993-04-16||Quebec||Findings
|M93C0003||Striking Bulk carrier Nirja and tanker Hamilton Energy||1993-12-11||Ontario||Finding—The pilot had been on duty for some 22 hours without restorative sleep and this probably adversely affected his performance.
|M92W1066||Collision Bulk carrier Nand Anant and fishing vessel Carmanah No. 1||1992-08-29||British Columbia||Findings
Table 3. Aviation investigation reports
|A17Q0050||Collision with wires, Exact Air||2017-04-30||Quebec||Finding as to cause—Sensation seeking, mental fatigue, and an altered risk perception very likely contributed to the fact that, immediately after completing the magnetometric survey work, the pilot flying descended to an altitude varying between 100 and 40 feet above ground level and maintained this altitude until the aircraft collided with the wires.|
|A16P0180||Loss of control and collision with terrain, privately operated Beaver aircraft||2016-10-10||British Columbia||Finding as to risk—If pilots do not obtain quality sleep during the rest period prior to flying, there is a risk that they will operate an aircraft while fatigued, which could degrade pilot performance.|
|A16O0016||Runway incursion and risk of collision, Air Canada||2016-01-30||Ontario||Finding as to risk—If required commuting flights are not included as part of the pilot's duty day, there is an increased risk of pilots operating while fatigued due to prolonged periods of wakefulness.|
|A16A0084||Collision with wires, privately operated helicopter||2016-09-04||New Brunswick||Finding as to risk—If pilots do not take advantage of opportunities to sleep between duty periods, there
is an increased risk of degraded performance due to fatigue.
|A15O0031||In-flight breakup, privately operated Piper aircraft||2015-03-17||Ontario||Finding as to cause—Given the pilot's expired qualifications, lack of recent experience, and levels of chronic stress and fatigue, he was neither qualified nor fit to undertake the flight on the day of the occurrence.|
|A15H0002||Collision with terrain, Air Canada||2015-03-29||Nova Scotia||Finding as to risk—If Transport Canada does not consistently follow its protocol for the assessment of aeromedical risk and ongoing surveillance in applicants who suffer from obstructive sleep apnea, some of the safety benefit of medical examinations will be lost, increasing the risk that pilots will fly with a medical condition that poses a risk to safety.
Other finding—Given that the captain rarely used continuous positive airway pressure therapy, he would have been at risk of experiencing fatigue related to chronic sleep disruption caused by obstructive sleep apnea. However, there was no indication that fatigue played a causal or contributory role in this occurrence.
|A13H0001||Controlled flight into terrain, Ornge medevac helicopter||2013-05-31||Ontario||Finding as to risk—If pilots engage in other work-related activities before the commencement of scheduled flight duty time, there is a risk that regulatory flight duty time limitations will be exceeded, which may degrade performance due to fatigue.|
|A13C0105||Loss of control – collision with water, Transwest Air Limited Partnership||2013-08-22||Northwest Territories||Finding as to cause—Cumulative unmanaged stressors disrupted the pilot's processing of safety-critical information, and likely contributed to an unsafe decision to depart with a damaged, uninspected aircraft. Specifically, the pilot's fatigue, in combination with illness, anger, heavy workload, time pressure, and the tree strike, reduced the resources available to gather and systematically process safety-critical information, resulting in a decision to depart with a damaged, uninspected aircraft.|
|A12W0004||Runway overrun, Enerjet||2012-01-09||British Columbia||Findings as to cause
Findings as to risk
|A12Q0216||Low-energy rejected landing and collision with terrain, Perimeter Aviation||2012-12-22||Nunavut||Finding as to cause—Frustration, fatigue, and an increase in workload and stress during the instrument approaches resulted in crew attentional narrowing and a shift away from well-learned, highly practised procedures.|
|A11F0012||Pitch excursion, Air Canada||2011-01-14||North Atlantic Ocean||Findings as to cause
Finding as to risk—North American-based pilots flying eastbound at night towards Europe are at increased risk of fatigue-related performance decrements.
|A10H0004||Runway overrun, Trans States Airlines LLC||2010-06-16||Ontario||Finding as to risk—Fatigue creates a risk of performance decrements in aircraft operations, and work-rest rules did not necessarily prevent flight crews from being fatigued.|
|A09Q0003||Controlled flight into trees, privately operated Piper Cherokee||2009-01-06||Quebec||Finding as to risk—The pilot undertook an extended night flight at the end of the day, with a planned return flight the same day. As a result, the pilot ran the risk of fatigue that may have led to degradation of performance.|
|A08O0233||Uncontrolled descent into terrain, privately operated Cessna||2008-09-01||Ontario||Findings as to cause
Finding as to risk—Reliance on a pilot's own judgment to prevent fatigue-related accidents is an ineffective defence mechanism.
|A08C0164||Airspeed decay – Uncommanded descent, Air Canada Jazz||2008-08-01||Manitoba||Finding as to risk—Although it is unlikely that the crew were fatigued at the time of the occurrence, the captain's work schedule resulted in irregular sleep patterns that had the potential to increase the risk of fatigue and fatigue-related performance decrements.|
|A07O0305||Runway incursion, R & M Aviation Inc.||2007-11-15||Ontario||Finding as to risk—A crew's alertness may be reduced by operational pressures and fatigue associated with a long duty day and multi-leg scheduling.|
|A07O0273||Collision with trees on approach, Ukrainian Cargo Airways||2007-10-04||Ontario||Finding as to risk—On several occasions prior to the occurrence flight, the crew did not receive the 42-hour rest period required by Ukrainian Cargo Airways' procedures after completing trans-meridian flights, potentially increasing the risk of operating while fatigued.|
|A05W0109||Inadvertent stick shaker at high altitude, Air Canada Jazz||2005-06-10||Alberta||Finding as to cause—The captain was not well rested before the flight. The effects of fatigue likely resulted in a degradation of his concentration and prolonged diversion of attention from monitoring of airspeed after power reduction. The airspeed was therefore allowed to fall below the targeted value.|
|A04W0032||Landing beside the runway, Bradley Air Services Ltd. (First Air)||2004-02-25||Alberta||Finding as to risk—Neither the Canadian Aviation Regulations nor the First Air Operations Manual provides sufficient defences concerning the scheduling of crew duty periods so that extended periods of wakefulness, lack of restorative sleep and rapid changes in crew shift times do not unduly affect crew performance.|
|A04H0004||Reduced power at take-off and collision with terrain
MK Airlines Limited
|2004-10-14||Nova Scotia||Findings as to cause
|A04H0001||Loss of control, Georgian Express Ltd.||2004-01-17||Ontario||Finding as to cause—On this flight, the pilot's lack of appreciation for the known hazards associated with the overweight condition of the aircraft, ice contamination, and the weather conditions was inconsistent with his previous practices. His decision to take off was likely adversely affected by some combination of stress and fatigue.|
|A01O0210||Controlled flight into terrain, privately operated Cessna||2001-08-03||Ontario||Finding as to cause—It is likely that fatigue affected the pilot's performance, and may have contributed to the accident.|
|A00W0217||Collision with terrain, Summit Air Charters Ltd.||2000-10-08||Northwest Territories||Finding as to risk—Given the pilot's flying time during the 30 days before the accident, the pilot's performance might have been affected by fatigue.|
|A99W0043||Wing strike on landing, Delta Air Lines||1999-03-10||Alberta||Finding as to risk—The captain and the second officer were subjected to a long work day because, in addition to the duty day required to operate the flights, they had commuted to their base of operation by air early on the morning of the flight. Long work days may contribute to fatigue.|
|A99Q0151||Controlled flight into terrain, Régionnair Inc.||1999-08-12||Quebec||Findings as to risk
|A97Q0183||Wire strike on take-off, privately operated Piper Aztec||1997-08-22||Quebec||Finding as to cause—The pilot was fatigued, because he did not take enough rest in preparation for the flight.|
|A97P0207||Collision with terrain, Northern Mountain Helicopters Inc.||1997-07-30||British Columbia||Findings as to risk
|A95W0093||Weather-related event, Continental Helicopters||1995-06-13||Yukon Territory||Finding as to cause—The pilot's flying activities in the period prior to the accident were conducive to fatigue.|
|A95Q0210||Controlled flight into terrain, privately operated Cessna||1995-10-22||Newfoundland and Labrador||Finding as to risk—The pilot had been on duty for a long period, which possibly affected his performance.|
|A95P0007||Collision with water, privately operated Piper||1995-01-12||British Columbia||Finding as to cause—The pilot reportedly had little sleep in the previous 24 hours and may have been fatigued.|
|A94C0119||Collision with terrain, privately operated Cessna||1994-06-29||Saskatchewan||Finding as to cause—The pilot's flying and non-flying duties resulted in long hours of work. As a result, he may have been suffering from fatigue.|
|A94C0088||Controlled flight into obstacle and terrain, Keewatin Air Limited||1994-06-01||Manitoba||Finding as to cause—Pilot fatigue and personal stress likely adversely affected the performance of the pilot flying.|
|A93W0204||Marine power loss/loss of control, Arctic Wings and Rotors||1993-12-03||Northwest Territories||Finding as to risk—While it cannot be determined that fatigue contributed to this accident, the pilot's recent work schedule was conducive to fatigue.|
|A91H0004||Collision with terrain, Government of Quebec||1991-06-19||Quebec||Findings as to risk
The number of TSB occurrences in which fatigue was a contributing factor or a risk was corrected on November 23 2020. The total number of occurrences was previously published as 99—34 in aviation, 36 in marine, and 29 in the rail sector. This number was updated to 91—34 in aviation, 28 in marine, and 29 in the rail sector
The changes were made to correct an error in data entry for the marine sector, as well as to remove 4 occurrences that had been included in 2018 but were determined subsequently (in 2020) not to meet criteria for fatigue in operational personnel, and to include 2 additional investigation reports published between 2018 and 2020 of fatigue-related occurrences that happened prior to 2018 (R17D0123, M17P0244).