This report describes the work performed during Phase IV compliance testing of light-emitting diode (LED) fixtures used as locomotive headlights and auxiliary lights. The purpose was to study the performance of the lamps under severe cold weather conditions. Researchers sought to determine whether LED lamps could melt a 1/4-inch-thick layer of ice from a lens surface and whether the lamps would accumulate a coating of snow and ice when operated in the presence of very cold, windblown snow. Throughout the testing, halogen lamps, currently standard equipment on freight locomotives, were used as a performance benchmark.

See Also:

• Compliance Testing for Locomotive LED Headlights and Auxiliary Lights, Phase I
• Compliance Testing for Locomotive LED Headlights and Auxiliary Lights, Phase II
• Compliance Testing for Locomotive LED Headlights and Auxiliary Lights, Phase III