The FRA requirement for "Part 223" bullet - resistant window glazing was necessary but expensive for the nations' railroads. The rule applied to any equipment that was occupied by crew members or passengers, which was a big hit in the wallet for Amtrak & private car owners too. In addition to replacing the EMD " L " - shaped windshield with smaller, cheaper glass, the RR's also welded up the extra side windows on EMD switchers, and on those EMD & GE units that had them. As well, many cabooses ( cabeese ??? ) became " Coffin Cars ", with virtually all side windows plated over except in the cupola or bay windows.