British Railways BR31170: LMS AC Electrified Lines Working Instructions (1960) was an operational handbook produced during the early adoption of 25 kV AC electrification on former LMS routes. It provided detailed guidance for drivers, guards, signalmen, and engineering staff on working safely and efficiently under overhead line equipment. Instructions covered traction current arrangements, isolations, protection of staff, emergency procedures, and communication protocols. The document reflected transitional practices as steam and electric traction operated side by side. BR31170 was an important reference in standardising procedures and ensuring safety as British Railways modernised its infrastructure.
