Job Description for Signal Maintainer. Signal maintainers are tasked with keeping railroads, subways, and other metro rail systems operating in peak condition. They help to maintain the electronic signs, crossing signals, and track switches, which are integral to any modern rail system, and perform routine inspections and maintenance on these systems. They also perform repairs as necessary and respond to emergencies called in by rail operators or local transport officials, as well as log and document all inspections and repairs performed. Signal maintainers also help perform repairs and installations of replacement or new equipment as needed. They may be alerted to malfunctioning signals by rail operators or system-generated feedback, and local transportation and police may also inform signal maintainers about key safety items like crossing gates and signals. The maintainer quickly assesses the repair requirements and performs them as needed. In all areas of inspection and repair, it is important that the maintainer keeps fastidious records and documentation of work performed, as this documentation may be required by government safety inspectors or investigators in the event of a derailment or other catastrophic failure.