49 C.F.R. § 236.53 Track circuit feed at grade crossing.
Title 49 - Transportation
At grade crossing with an electric railroad where foreign current is present, the electric energy for noncoded direct current track circuit shall feed away from the crossing.
Title 49: Transportation
PART 236—RULES, STANDARDS, AND INSTRUCTIONS GOVERNING THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES
Subpart A—Rules and Instructions: All Systems
Track Circuits
§ 236.53 Track circuit feed at grade crossing.