Or there was a lighting failure in some parts of the station, or a general electricity problem.

Reactive maintenance is a direct response to a lighting failure, such as replacing a discharge lamp after it has failed, or replacing an entire lighting unit after it has been hit by a vehicle.

Each drill team is allowed only one 9:00 minute session which is then critiqued by a panel of judges, however, a team will be allowed to start over in the case of an unexpected interruption, such as a lighting failure.

At a news conference here, David S. Rayburn, the lead investigator for the National Transportation Safety Board, said a preliminary inquiry suggested that the lighting failure and slick roadway were a deadly combination on a curved portion of highway where numerous fatal accidents have occurred in recent years.

During the winters of both 2009-2010 and 2010-2011, fine powdery snow settling on the Auxiliary Control Modules (ACMs) melted by warmer air led to water leaking into the ACMs, causing damage and their shutdown, subsequently causing passenger information system, heating, and lighting failure in some carriages.