A fatal 2013 train accident in New York has prompted the Metro-North to ask for a sleep disorder screening program, as reported by Lohud.

Sleep apnea robs a person of rest when the tongue blocks the airway, awakening the person repeatedly. The condition went undiagnosed in engineer William Rockefeller until he fell asleep at the controls of a speeding train that entered a sharp curve in the Bronx. The resulting derailment, on Dec. 1, 2013, killed four and injured dozens.