The National Transportation Safety Board is out with a pair of recommendations, following December's deadly Metro North train derailment.

The agency said Metro North should install video cameras in train cabs, facing both inwards and outwards.  The NTSB also suggested installing permanent signs where speed is restricted.

"There's nothing novel or hi-tech about cameras facing inward and outward," Connecticut Senator Richard Blumenthal said.  "There's nothing particularly expensive about it.  It should be standard operating equipment."

Four people were killed on December 1, when a Metro North train derailed in the Bronx north of the Spuyten Duyvil station.  The train was going 82 mph into a turn where speed is restricted to 30 mph.

"It seemed highly likely that the accident was caused by a train conductor who nodded off at the controls," said New York Senator Chuck Schumer.

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