In the United States there is no federal requirement to objectively screen for sleep disorders in commercial motor vehicle drivers, rail workers, or pilots. The medical examinations required for each profession typically ask a screening question such as, “Do you have sleep disorders, pauses in breathing while asleep, daytime sleepiness, loud snoring?” However, this subjective questionnaire approach has been documented as failing to capture most commercial drivers with sleep disorders because they often fail to report these symptoms even when they are present.^23,24

If a sleep disorder is not captured on a preplacement or routine medical assessment and an accident happens, courts have generally found both the driver and the employer responsible for the accident, reasoning that sleepiness is recognizable by drivers and that accidents resulting from falling asleep are reasonably foreseeable.²⁵ Although most driving case law has addressed cases involving the general public and found the driver has a duty to pull off the road to rest when fatigued,^13,25 courts surely extend this expectation to commercial drivers, whom they hold to a higher standard.

An illustrative example of an employer being found liable for a sleep-related accident by one of its employees is Dunlap v W.L. Logan Trucking Co., in which the driver of a tractor trailer fell asleep at the wheel, killing a woman.¹⁷ In this case, the court found the employee directly liable and the employer vicariously liable for the death because the employee was acting within the scope of his employment.

A more recent example occurred 2013 when a Greyhound bus went off the road in Ohio and flipped over less than an hour into its journey.²⁶ Six passengers were ultimately awarded $6 million for their injuries, which included compound fractures, multiple surgeries, as well as neck and back injuries. From an employer’s perspective, this case is significant because the driver was evaluated for a Department of Transportation Medical Certification examination 6 weeks before the accident occurred. The examining physician determined the driver was at risk of OSA and recommended that he undergo an in-laboratory sleep study and only issued a 3-month medical certification, rather than the typical 1-year to 2-year certification that the driver had received after prior examinations. Instead of requiring the recommended sleep study, which the employer’s written policy also required, the driver was directed to follow up in a medical clinic, where he was cleared of sleep apnea based only on a limited physical examination and was allowed to return to work by his employer without the requisite sleep study. Two days later, the fatigue-related accident occurred. At deposition, Greyhound’s medical director acknowledged that “A physical exam alone is not going to say one way or the other whether a person has sleep apnea.”²⁶

For an employer invested in fatigue risk management, the identification of a driver at high risk for OSA during his medical certification should have triggered further medical review by the company’s medical director, leading to compliance with the recommended diagnostic tests and possible suspension of safety-sensitive operations by that employee until they were sufficiently evaluated and treated.

Depending on where a transportation company operates, it is also important for employers to recognize that some states go beyond allowing injured parties to sue for monetary compensation. For example, Arkansas and New Jersey have laws that explicitly make it a crime to drive while drowsy, meaning the driver can go to prison for up to 10 years and face a fine up to $100,000 for vehicular homicide.^27,28 Although both of these laws require the driver to have been awake (not necessarily driving) for the preceding 24 hours for the law to apply, states such as Maine, New York, and Tennessee have all considered laws that would make it a crime if the driver is simply impaired by fatigue.^29-31 Even in places where there is no threshold established in legislation, in any tragic accident drivers may still find themselves facing a prosecutor and jury trying to decide how tired is too tired to drive. Because studies have shown people are poor judges of their own impairment from fatigue and sleepiness, it is critical that employer controls and programs are in place to identify, monitor, and manage fatigue-related safety risks.^14,18-20

Approximately 30 million adults in the United States are shift workers: those who work outside the traditional 9 am to 5 pm work day. Of these shift workers, 10% meet criteria for a shift work disorder by experiencing insomnia or excessive sleepiness during wakefulness accompanied by a reduction of total sleep time not caused by voluntary sleep restriction.³⁴

Transportation workers are over-represented among shift workers, which challenges them to work safely because their natural circadian cycles diminish alertness during the performance of safety-critical tasks at night.³⁴ Accidents in the transportation industry also commonly result from decreased vigilance caused by excessive daytime sleepiness as a consequence of disruptions in the natural sleep-wakefulness cycles of shift workers. In addition, shiftwork and OSA cause synergistic and significant impairment.²³ Therefore, employees with OSA should preferably work during daytime hours on nonrotating shifts even when treated with CPAP.

If shiftwork is unavoidable, schedules should be informed by the latest sleep research, designed to optimize short-term and long-term health benefits and minimize sleep disturbance. For example, many chronobiologists recommend fast-forward rotating shifts, in which workers transition clockwise from day to evening to night over intervals of 2 to 3 days, with 2 to 3 days off for recovery following the night shift. The fast rotation prevents permanent shifts in circadian cycles and helps to minimize accumulation of sleep debt.³⁵

A 2016 survey of transportation workers and their employers found that workers were less likely than their employers to consider fatigue and sleepiness to be significant safety risks.¹⁰ Employers can help raise awareness of fatigue as a major factor in transportation safety and the measures they are taking to mitigate the risk. Sleep hygiene and fatigue management training should be incorporated into safety training and monitoring programs. In addition, employers can educate workers on the health benefits the employees can reap as individuals by making healthy sleep an integral part of their personal and professional responsibilities.

Employers should create a culture in which fatigue-related safety is valued and supported by policies and practices. Care must be taken so as not to create perverse incentives, whereby employees may be penalized for not continuing to work when too fatigued or sleepy to do so. For example, members of the Owner-Operator Independent Drivers Association have expressed concern that regulations designed to keep them safe can paradoxically force them to stay on the road when dispatchers at companies that hire their services cite these regulations in support of assigning additional tasks, without regard to road and traffic conditions, weather, and driver fatigue that may jeopardize safety.³⁶ These drivers express feeling compelled to accept these assignments despite fatigue or adverse conditions, because the employer expects they can work to the limits of the regulation. Employers should keep in mind that although the Federal Motor Carrier Safety Administration (FMCSA) regulations were established to limit sleepy drivers on the road, complying with the regulations does not guarantee a driver will not be fatigued, and employers are encouraged to trust their drivers when they are tired or in adverse road conditions.

Employers should screen individuals considered for safety-sensitive positions for sleep disorders, including OSA. Employers should be concerned about untreated OSA because it has been linked to $65 billion to $165 billion in costs caused by lost productivity as well as increased health and safety costs and higher rates of accidents.⁶

Objective screening criteria are preferred because commercial drivers usually do not report their symptoms because of concerns (perceived or real) of the negative economic and occupational impact of an OSA diagnosis.^6,23 These concerns range from the inconvenience of diagnostic testing and treatment to loss of income and employment. Accordingly, screening should use and rely primarily on objective risk factors such as male gender, age, body mass index (BMI), neck circumference, and hypertension, rather than subjective self-reported symptoms.

Although not required by regulation,¹¹ to mitigate the significant threat of substantial harm to employees and the general public, employers should require safety-sensitive transit workers to undergo testing for OSA who meet the following criteria³⁷:

Workers diagnosed with OSA should be disqualified from safety-sensitive tasks until they are successfully treated.

Employers in the transportation industry and their occupational physicians should be vigilant regarding the medications their workers are taking because many can affect daytime alertness. As a general rule, medications depressing the central nervous system deserve careful deliberation in transportation workers because they can adversely affect safety-sensitive duties.³⁴ In addition, although there may be temptation to prescribe wake-promoting stimulants (eg, modafinil, armodafinil), these are not a substitute for fatigue prevention and management strategies, and should only be used in specific cases with expert guidance as adjuncts.

FMCSA regulation section 391.41(b)(12) states:

A person is physically qualified to drive a commercial motor vehicle (CMV) if that person does not use a controlled substance identified in 21 CFR 1308.11, Schedule I, an amphetamine, a narcotic, or any other habit-forming drug. Exception: A driver may use such a substance or drug, if the substance or drug is prescribed by a licensed medical practitioner who is familiar with the driver’s medical history and assigned duties; and has advised the driver that the prescribed substance or drug will not adversely affect the driver’s ability to safely operate a CMV. This exception does not apply to methadone.

Medical examiners are required to carefully assess the effects of a driver’s medications on their ability to operate a vehicle safely before qualifying the driver to do so commercially.

Employee education is also critical in this regard, because common over-the-counter medications, supplements, and legally obtained prescriptions may be disqualifying when they adversely affect the driver’s ability to drive safely.^38-45

Table 1 gives guidance to prescribing physicians providing care to transportation workers regarding common medications that have sedating side effects,³⁴ which the FMCSA advises against in transportation workers, and offers alternatives that could be considered.

As with any hazard, if elimination of risk is not possible, engineering controls to mitigate risk are desirable rather than relying on individual human factors or performance, such as the application of personal protective equipment or safety practices (eg, the strategic use of caffeine and napping) to effectively minimize the hazard. Employers in the transportation industry can use increasingly sophisticated systems to detect and even compensate for sleepy drivers and operators. For example, an automated braking system at rail stations and turns acts as an operator-independent failsafe against speed-related derailments or crashes, which have caused catastrophic accidents in the past. As automated driving technologies mature in the coming years, employers in the trucking industry can integrate technologies that both detect driver fatigue and intervene to keep them alert, and also take control of the vehicle to avoid lane departures, speeding, and collisions. This technology is increasingly available in consumer vehicles, and can assist with lane control, warning when an obstacle is ahead, and braking before a collision is detected by the driver. Other available technologies include computer-analyzed steering wheel movements to detect when a driver is fatigued, but before the driver falls asleep. Devices that directly monitor a driver’s eyes or electrodermal activity can also detect fatigue before the driver falls asleep, triggering an alert to arouse the driver. It is anticipated that such technological engineering controls will play an integral role in improving transportation safety in the future.

Fatigue management plans organize and formalize employers’ efforts to minimize fatigue-related risk. They should include statements of intent and scope; clearly delineate work hours and overtime policies; identify fatigue-related safety issues; and outline mitigation strategies, including training, medical screening, engineering controls, and strategies for reporting and investigating fatigue-related incidents and near misses.

For fatigue management plans to succeed, they must be science based, data driven for the specific transit industry, cooperatively designed by all stakeholders, integrated into a culture of workplace safety and health management, and continuously improved using feedback and evaluation.⁴⁶ Senior leadership must nurture a culture of trust between managers and workers as well as having accountability for the program.⁶ A successful program will not only improve fatigue-related safety risk but also improve morale, productivity, work satisfaction, and well-being for employees and for the company.

In addition, as in all endeavors, ongoing research is integral to deepening the understanding of fatigue-related safety risk; its impact on employers, workers, and the public; and what methods are optimal for its mitigation. As shown by Schneider National, private corporations can collaborate in numerous ways with the scientific research community to further the collective understanding of how fatigue-related risk can be minimized in transportation safety. Employers of all sizes can contribute to ongoing research in numerous ways, including data collection, active collaborations with researchers, and through financial support of ongoing research. At a minimum, employers should analyze their own safety data, regularly evaluate their fatigue management plans, collect feedback from stakeholders, and track progress.