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CFR > Title 49 - Transportation > SUBTITLE B—Other Regulations Relating to Transportation > CHAPTER II—FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (Parts 200–269) > PART 236—RULES, STANDARDS, AND INSTRUCTIONS GOVERNING THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES > SUBPART G—Definitions (§236.700 to §236.838) > 236.824—System, automatic block signal.
236.824—System, automatic block signal.
A block signal system wherein the use of each block is governed by an automatic block signal, cab signal, or both.