Chronicle: Dead-man switch failed to stop train

Muni’s onboard master train-control lever, known in the transit industry as the dead-man’s device, failed to activate during July 18th’s crash between a K and L train at West Portal station when one of the light rail transit operators passed out for medical reasons. The lever, which requires a half a pound of pressure to keep the train in operation, was switched down from 2.5 pounds in 1996 after operators complained about hand and wrist problems from the amount of pressure.  Muni chief Nathaniel Ford says that Muni may consider increasing the amount of pressure on the lever as part of their efforts to bump up safty in the system.

Investigators have not yet concluded that the dead-man lever contributed to the West Portal crash.