U.S. Sen. Charles Schumer (D-N.Y.) yesterday called on the U.S. Department of Transportation (USDOT) to reverse its decision to drop a proposed rule that could have required railroads to test train engineers for obstructive sleep apnea.

In a letter to USDOT Secretary Elaine Chao, Schumer said the proposed rule was a “modest, common-sense approach to combating fatigue on our roads and rails.”

The rule would have required testing for obstructive sleep apnea if it caused any performance problems.

Schumer noted that the National Transportation Safety Board (NTSB) has linked obstructive sleep apnea to a number of fatal truck and rail accidents. Last week, the NTSB determined that two commuter-rail accidents in the New York City area were the result of undiagnosed cases of sleep apnea in the trains’ engineers.

One of those accidents caused a fatality and injured more than 100 others when a New Jersey Transit train crashed into a terminal in Hoboken, New Jersey.

“I urge you to immediately reconsider your decision to withdraw the proposed rule in order to help avoid future fatigue-related tragedies,” Schumer wrote to Chao.

Sleep apnea is a medical disorder in which breathing repeatedly stops and starts while a person is sleeping, resulting in insufficient sleep. Left untreated, someone with the disorder may involuntarily fall asleep when he/she is supposed to be awake.