Latest posts by Michael Morgenstern, MD (see all)
On December 1st, 2013, a Metro North passenger train derailed in the Bronx, NY, killing 4, injuring 61 and causing $9 million in property damage. Unfortunately, this accident was not a lone event. According to the Federal Railroad Administration (FRA) Office of Safety Analysis there were 11,233 train incidents including 1,856 accidents and 1,314 derailments in 2015, resulting in 821 lives lost. Among commuter trains, 1,453 passengers were injured and 17 were killed. While the lives lost are the greatest tragedy, the financial costs of these disasters are also massive. Statistics indicate that over the next two decades a subset of trains carrying ethanol or crude oil will derail 10 times per year, resulting in at least $4 billion in damages according to estimates by the Department of Transportation. This figure could be significantly greater if a single railway disaster takes place in a densely populated area like New York City, where damages from such a disaster could reach $11.8 billion.
In October of 2014, the National Transportation Safety Board (NTSB) concluded that the Metro North derailment was caused by the driver of the train falling asleep due to undiagnosed obstructive sleep apnea (OSA). A five-year study of main-track train collisions by the FRA found that 30% of collisions are related to fatigue.
The Federal Railway Administration (FRA), in conjunction with the Federal Motor Carrier Safety Administration (FMCSA), published a request for comment in the Federal Register in docket numbers MCSA-2015-0419 and FRA-2015-0111 to gather information related to the evaluation of safety sensitive personnel for moderate to severe OSA. In response to this request, the American Sleep Apnea Society has prepared this white paper (which will be posted here in various parts over the next coming days) to address specific questions provided by the agencies.
Given the high prevalence of OSA in railway drivers, the need for screening is urgent. Data suggests that 35% to 62% of railways workers have sleep apnea—a rate that is two to four times greater than the general population. As in the general population, the prevalence increases with risk factors such as age and obesity. A significant amount of these disasters could be prevented by proper screenings that identifies drivers who are likely to be impaired by fatigue.
A comprehensive approach should include testing for the presence of sleep apnea, evaluation for signs of functional impairment, and worker education to prevent and counteract sleepiness during work. . Railway workers provide an invaluable service. The lives of others are often dependent on their ability to drive a train while fully functional, at any time, whether at 4 PM or at 4 AM. Since research has demonstrated that self-reported symptoms of sleep apnea in transportation workers are often unreliable, all railway workers in safety sensitive positions should be routinely tested for sleep apnea and impaired function using objective measures.
Those certified to drive a train should:
- Have no sign of sleep apnea on Home Sleep Testing (HST), Polysomnography (PSG), or provide evidence of successful sleep apnea treatment.
- Pass a driving simulator test that mimics nighttime conditions and/or a maintenance of wakefulness test, demonstrating that they do not have a high likelihood of falling asleep when they need to be alert.
Additionally, railway workers should be educated about the risk of driving while sleepy, instructed on proper sleep hygiene, and encouraged to utilize caffeine, rest stops and naps to counteract sleepiness when they are working. A comprehensive screening program in railway drivers should also incorporate safety data collection, so that the benefits of restrictions could be evaluated over time and improved upon. Sleep apnea screening programs can be used to complement other promising technologies such as positive train control (PTC) systems to improve overall railway safety.
Implementation of these recommendations will reduce fatigue related collisions, benefit the health and longevity of railway workers, and reduce their healthcare costs over time. In general, patients with untreated OSA are more likely to have worsening or development of obesity, depression, hypertension, diabetes, stroke, coronary artery disease and cardiac arrhythmias. Their average annual health care costs compared to those without sleep apnea are greater by $1950 to $3899. Therefore, screening of railway workers can efficiently reduce collisions, improve health and result in cost savings.