1. n. [Drilling]

A steel cable attached to the rig derrick or mast near the work platform for the derrickman. This cable is anchored at surface level (on a vessel or the Earth) away from the mast in a loose catenary profile, and fitted with a handle and hand brake that is stored at the top. The escape line provides a rapid escape path for the derrickman should well conditions or massive mechanical failure warrant. In such a case the derrickman would disconnect his safety belt from the rig, rehook it over the escape line if time permitted, firmly grip the tee-bar handle and ride the trolley down the cable while holding on to the handle with his hands. The escape line is also known as the "Geronimo line."

See related terms: derrick,  derrickman,  mast