49 C.F.R. Subpart A—Rules and Instructions: All Systems
Title 49 - Transportation
As required for maintenance, plans shall be kept at all interlockings, automatic signals and controlled points. Plans shall be legible and correct. [49 FR 3382, Jan. 26, 1984] Each circuit, the functioning of which affects the safety of train operations, shall be kept free of any ground or combination of grounds which will permit a flow of current equal to or in excess of 75 percent of the release value of any relay or other electromagnetic device in the circuit, except circuits which include any track rail and except the common return wires of single-wire, single-break, signal control circuits using a grounded common, and alternating current power distribution circuits which are grounded in the interest of safety. Signal apparatus housings shall be secured against unauthorized entry. [49 FR 3382, Jan. 26, 1984] The normal functioning of any device shall not be interfered with in testing or otherwise without first taking measures to provide for safety of train operation which depends on normal functioning of such device. [49 FR 3382, Jan. 26, 1984] All control circuits the functioning of which affects safety of train operation shall be designed on the closed circuit principle, except circuits for roadway equipment of intermittent automatic train stop system. Hand-operated switch equipped with switch circuit controller connected to the point, or with facing-point lock and circuit controller, shall be so maintained that when point is open one-fourth inch or more on facing-point switch and three-eights inch or more on trailing-point switch, track or control circuits will be opened or shunted or both, and if equipped with facing-point lock with circuit controller, switch cannot be locked. On such hand-operated switch, switch circuit controllers, facing-point locks, switch-and-lock movements, and their connections shall be securely fastened in place, and contacts maintained with an opening of not less than one-sixteenth inch when open. Circuit controller operated by switch-and-lock movement shall be maintained so that normally open contacts will remain closed and normally closed contacts will remain open until the switch is locked. Signal apparatus, the functioning of which affects the safety of train operation, shall be maintained in accordance with the limits within which the device is designed to operate. [49 FR 3382, Jan. 26, 1984] Signal control and electric locking circuits shall not be selected through the contacts of instruments designed primarily for indicating or annunciating purposes in which an indicating element attached to the armature is arranged so that it can in itself cause improper operation of the armature. Electric locks on new installations and new electric locks applied to existing installations shall be of the forced drop type. When any component of a signal system, the proper functioning of which is essential to the safety of train operation, fails to perform its intended signaling function or is not in correspondence with known operating conditions, the cause shall be determined and the faulty component adjusted, repaired or replaced without undue delay. [49 FR 3382, Jan. 26, 1984] Signal protection shall be provided for facing and trailing movements through spring switch within interlocking limits and through spring switch installed in automatic block signal, train stop, train control or cab signal territory where train movements over the switch are made at a speed exceeding 20 miles per hour, except that signal protection shall be required only with the current of traffic on track signaled for movement in only one direction. Note: Does not apply to spring switch installed prior to October 1, 1950 in automatic block signal, automatic train stop, or automatic train control territory. [49 FR 3383, Jan. 26, 1984] The control circuits of signals governing facing movements over a main track spring switch shall be selected through the contacts of a switch circuit controller, or through the contacts of relay repeating the position of such circuit controller, which, when normally closed switch point is open one-fourth inch or more, will cause such signals to display their most restrictive aspects, except that where a separate aspect is displayed for facing movements over the switch in the reverse position the signal shall display its most restrictive aspect when the switch points are open one-fourth inch or more from either the normal or reverse position. (a) The indication of signal governing movements from siding to main track with the current of traffic on track signaled for movements in only one direction through a spring switch in automatic block signal territory shall be not less restrictive than “Proceed at Restricted Speed' when the block, into which movements are governed by the signal, is occupied, and shall be “Stop” when the main track is occupied by a train approaching the switch within at least 1,500 feet in approach of the approach signal located stopping distance from the main track signal governing trailing movements over switch, except that the indication may be caused to be less restrictive if approach or time locking is used. (b) The indication of signal governing movements against the current of traffic from the reverse main of main tracks to a single track, or signal governing movements from a siding to a main track signaled for movements in either direction, through a spring switch, in automatic block signal territory, shall be not less restrictive than “Proceed at Restricted Speed” when the block, into which movements are governed by the signal, is occupied by a preceding train, and shall be “Stop” when the block on the single track into which the signal governs is occupied by an opposing train. (c) The indication of signal governing movements against the current of traffic from the reverse main of main tracks to a single track or signal governing movements from a siding to a main track signaled for movements in either direction through a spring switch in automatic block signal territory shall be “Stop” when the normal direction main track of the double track or the single track signaled for movements in both directions is occupied by a train approaching the switch within at least 1,500 feet in approach of the approach signal located stopping distance from the main track signal governing trailing movements over switch, except that indication may be caused to be less restrictive if approach or time locking is used. Automatic block, traffic control, train stop, train control and cab signal territory shall be designated in timetable instructions. When an electric lock releasing circuit is provided on the main track to permit a train or an engine to diverge from the main track without time delay, the circuit shall be of such length to permit occupancy of the circuit to be seen by a crew member stationed at the switch. When the releasing circuit extends into the fouling circuit, a train or engine on the siding shall be prevented from occupying the releasing circuit by a derail either pipe-connected to switch point or equipped with an independently operated electric lock. [49 FR 3383, Jan. 26, 1984] (a) Steel or wrought-iron pipe one inch or larger, or members of equal strength, shall be used for operating connections for switches, derails, movable-point frogs, facing-point locks, rail-locking devices of movable bridge protected by interlocking, and mechanically operated signals, except up-and-down rod which may be three-fourths inch pipe or solid rod. Pipe shall be fully screwed into coupling and both ends of each pipe shall be riveted to pipe plug with 2 rivets. (b) Pipeline shall not be out of alignment sufficiently to interfere with proper operation, shall be properly compensated for temperature changes, and supported on carriers spaced not more than 8 feet apart on tangent and curve of less than 2° and not more than 7 feet apart on curve of 2° or more. With lever in any position, couplings in pipe line shall not foul carriers. [49 FR 3383, Jan. 26, 1984] (a) Within 6 months of June 6, 2005, each railroad shall develop and adopt a software management control plan for its signal and train control systems. A railroad commencing operations after June 6, 2005, shall adopt a software management control plan for its signal and train control systems prior to commencing operations. (b) Within 30 months of the completion of the software management control plan, each railroad shall have fully implemented such plan. (c) For purposes of this section, “software management control plan” means a plan designed to ensure that the proper and intended software version for each specific site and location is documented (mapped) and maintained through the life-cycle of the system. The plan must further describe how the proper software configuration is to be identified and confirmed in the event of replacement, modification, or disarrangement of any part of the system. [70 FR 11095, Mar. 7, 2005]
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
General
§ 236.1 Plans, where kept.
§ 236.2 Grounds.
§ 236.3 Locking of signal apparatus housings.
§ 236.4 Interference with normal functioning of device.
§ 236.5 Design of control circuits on closed circuit principle.
§ 236.6 Hand-operated switch equipped with switch circuit controller.
§ 236.7 Circuit controller operated by switch-and-lock movement.
§ 236.8 Operating characteristics of electromagnetic, electronic, or electrical apparatus.
§ 236.9 Selection of circuits through indicating or annunciating instruments.
§ 236.10 Electric locks, force drop type; where required.
§ 236.11 Adjustment, repair, or replacement of component.
§ 236.12 Spring switch signal protection; where required.
§ 236.13 Spring switch; selection of signal control circuits through circuit controller.
§ 236.14 Spring switch signal protection; requirements.
§ 236.15 Timetable instructions.
§ 236.16 Electric lock, main track releasing circuit.
§ 236.17 Pipe for operating connections, requirements.
§ 236.18 Software management control plan.
Roadway Signals and Cab Signals
§ 236.21 Location of roadway signals.
Each roadway signal shall be positioned and aligned so that its aspects can be clearly associated with the track it governs.
[49 FR 3383, Jan. 26, 1984]
§ 236.22 Semaphore signal arm; clearance to other objects.
At least one-half inch clearance shall be provided between semaphore signal arm, and any object that may interfere with its operation.
§ 236.23 Aspects and indications.
(a) Aspects shall be shown by the position of semaphore blades, color of lights, position of lights, flashing of lights, or any combination thereof. They may be qualified by marker plate, number plate, letter plate, marker light, shape and color of semaphore blades or any combination thereof, subject to the following conditions:
(1) Night aspects of roadway signals, except qualifying appurtenances, shall be shown by lights; day aspects by lights or semaphore arms. A single white light shall not be used.
(2) Reflector lenses or buttons or other devices which depend for visibility upon reflected light from an external source shall not be used hereafter in night aspects, except qualifying appurtenances.
(b) The aspects of cab signals shall be shown by lights or by illuminated letters or numbers.
(c) Each aspect displayed by a signal shall be identified by a name and shall indicate action to be taken. Only one name and indication shall apply to those aspects indicating the same action to be taken; the same aspect shall not be used with any other name and indication.
(d) The fundamental indications of signal aspects shall conform to the following:
(1) A red light, a series of horizontal lights or a semaphore blade in a horizontal position shall be used to indicate stop.
(2) A yellow light, a lunar light, or a series of lights or a semaphore blade in the upper or lower quadrant at an angle of approximately 45 degrees to the vertical, shall be used to indicate that speed is to be restricted and stop may be required.
(3) A green light, a series of vertical lights, or a semaphore blade in a vertical position in the upper quadrant or 60° or 90° in the lower quadrant shall be used to indicate proceed at authorized speed.
(e) The names, indications, and aspects of roadway and cab signals shall be defined in the carrier's Operating Rule Book or Special Instructions. Modifications shall be filed with the FRA within thirty days after such modifications become effective.
(f) The absence of a qualifying appurtenance, the failure of a lamp in a light signal, or a false restrictive position of an arm of a semaphore signal shall not cause the display of a less restrictive aspect than intended.
[33 FR 19684, Dec. 25, 1968, as amended at 49 FR 3383, Jan. 26, 1984]
§ 236.24 Spacing of roadway signals.
Each roadway signal shall be located with respect to the next signal or signals in advance which govern train movements in the same direction so that the indication of a signal displaying a restrictive aspect can be complied with by means of a brake application, other than an emergency application, initiated at such signal, either by stopping at the signal where a stop is required, or by a reduction in speed to the rate prescribed by the next signal in advance where reduced speed is required.
§ 236.25 [Reserved]
§ 236.26 Buffing device, maintenance.
Buffing device shall be maintained so as not to cause the signal to display a less restrictive aspect than intended.
Track Circuits
§ 236.51 Track circuit requirements.
Track relay controlling home signals shall be in deenergized position, or device that functions as a track relay controlling home signals shall be in its most restrictive state, and the track circuit of an automatic train stop, train control, or cab signal system shall be deenergized in the rear of the point where any of the following conditions exist:
(a) When a rail is broken or a rail or switch-frog is removed except when a rail is broken or removed in the shunt fouling circuit of a turnout or crossover, provided, however, that shunt fouling circuit may not be used in a turnout through which permissible speed is greater than 45 miles per hour. It shall not be a violation of this requirement if a track circuit is energized:
(1) When a break occurs between the end of rail and track circuit connector; within the limits of rail-joint bond, appliance or other protective device, which provides a bypath for the electric current, or
(2) As result of leakage current or foreign current in the rear of a point where a break occurs.
(b) When a train, locomotive, or car occupies any part of a track circuit, including fouling section of turnout except turnouts of hand-operated main track crossover. It shall not be a violation of this requirement where the presence of sand, rust, dirt, grease, or other foreign matter prevents effective shunting, except that where such conditions are known to exist adequate measures to safeguard train operation must be taken.
(c) Where switch shunting circuit is used:
(1) Switch point is not closed in normal position.
(2) A switch is not locked where facing-point lock with circuit controller is used.
(3) An independently operated fouling-point derail equipped with switch circuit controller is not in derailing position.
[33 FR 19684, Dec. 25, 1968, as amended at 49 FR 3383, Jan. 26, 1984]
§ 236.52 Relayed cut-section.
Where relayed cut-section is used in territory where noncoded direct-current track circuits are in use the energy circuit to the adjoining track shall be open and the track circuit shunted when the track relay at such cut-section is in deenergized position.
§ 236.53 Track circuit feed at grade crossing.
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.
§ 236.54 Minimum length of track circuit.
When a track circuit shorter than maximum inner wheelbase of any locomotive or car operated over such track circuit is used for control of signaling facilities, other means shall be used to provide the equivalent of track circuit protection.
[49 FR 3383, Jan. 26, 1984]
§ 236.55 Dead section; maximum length.
Where dead section exceeds 35 feet, a special circuit shall be installed. Where shortest outer wheelbase of a locomotive operating over such dead section is less than 35 feet, the maximum length of the dead section shall not exceed the length of the outer wheelbase of such locomotive unless special circuit is used.
[49 FR 3383, Jan. 26, 1984]
§ 236.56 Shunting sensitivity.
Each track circuit controlling home signal or approach locking shall be so maintained that track relay is in deenergized position, or device that functions as a track relay shall be in its most restrictive state if, when track circuit is dry, a shunt of 0.06 ohm resistance is connected across the track rails of the circuit, including fouling sections of turnouts.
[49 FR 3383, Jan. 26, 1984]
§ 236.57 Shunt and fouling wires.
(a) Except as provided in paragraph (b) of this section, shunt wires and fouling wires hereafter installed or replaced shall consist of at least two discrete conductors, and each shall be of sufficient conductivity and maintained in such condition that the track relay will be in deenergized position, or device that functions as a track relay will be in its most restrictive state, when the circuit is shunted.
(b) This rule does not apply to shunt wires where track or control circuit is opened by the switch circuit controller.
[49 FR 3383, Jan. 26, 1984]
§ 236.58 Turnout, fouling section.
Rail joints within the fouling section shall be bonded, and fouling section shall extend at least to a point where sufficient tract centers and allowance for maximum car overhang and width will prevent interference with train, locomotive, or car movement on the adjacent track.
[49 FR 3383, Jan. 26, 1984]
§ 236.59 Insulated rail joints.
Insulated rail joints shall be maintained in condition to prevent sufficient track circuit current from flowing between the rails separated by the insulation to cause a failure of any track circuit involved.
§ 236.60 Switch shunting circuit; use restricted.
Switch shunting circuit shall not be hereafter installed, except where tract or control circuit is opened by the circuit controller.
[49 FR 3384, Jan. 26, 1984]
Wires and Cables
§ 236.71 Signal wires on pole line and aerial cable.
Signal wire on pole line shall be securely tied in on insulator properly fastened to crossarm or bracket supported by pole or other support. Signal wire shall not interfere with, or be interfered by, other wires on the pole line. Aerial cable shall be supported by messenger.
[49 FR 3384, Jan. 26, 1984]
§ 236.72 [Reserved]
§ 236.73 Open-wire transmission line; clearance to other circuits.
Open-wire transmission line operating at voltage of 750 volts or more shall be placed not less than 4 feet above the nearest crossarm carrying signal or communication circuits.
§ 236.74 Protection of insulated wire; splice in underground wire.
Insulated wire shall be protected from mechanical injury. The insulation shall not be punctured for test purposes. Splice in underground wire shall have insulation resistance at least equal to the wire spliced.
§ 236.75 [Reserved]
§ 236.76 Tagging of wires and interference of wires or tags with signal apparatus.
Each wire shall be tagged or otherwise so marked that it can be identified at each terminal. Tags and other marks of identification shall be made of insulating material and so arranged that tags and wires do not interfere with moving parts of apparatus.
[49 FR 3384, Jan. 26, 1984]
Inspections and Tests; All Systems
§ 236.101 Purpose of inspection and tests; removal from service of relay or device failing to meet test requirements.
The following inspections and tests shall be made in accordance with specifications of the carrier, subject to approval of the FRA, to determine if the apparatus and/or equipment is maintained in condition to perform its intended function. Electronic device, relay, or other electromagnetic device which fails to meet the requirements of specified tests shall be removed from service, and shall not be restored to service until its operating characteristics are in accordance with the limits within which such device or relay is designed to operate.
[49 FR 3384, Jan. 26, 1984]
§ 236.102 Semaphore or searchlight signal mechanism.
(a) Semaphore signal mechanism shall be inspected at least once every six months, and tests of the operating characteristics of all parts shall be made at least once every two years.
(b) Searchlight signal mechanism shall be inspected, and the mechanical movement shall be observed while operating the mechanism to all positions, at least once every six months. Tests of the operating characteristics shall be made at least once every two years.
[49 FR 3384, Jan. 26, 1984]
§ 236.103 Switch circuit controller or point detector.
Switch circuit controller, circuit controller, or point detector operated by hand-operated switch or by power-operated or mechanically-operated switch-and-lock movement shall be inspected and tested at least once every three months.
[49 FR 3384, Jan. 26, 1984]
§ 236.104 Shunt fouling circuit.
Shunt fouling circuit shall be inspected and tested at least once every three months.
§ 236.105 Electric lock.
Electric lock, except forced-drop type, shall be tested at least once every two years.
§ 236.106 Relays.
Each relay, the functioning of which affects the safety of train operations, shall be tested at least once every four years except:
(a) Alternating current centrifugal type relay shall be tested at least once every 12 months;
(b) Alternating current vane type relay and direct current polar type relay shall be tested at least once every 2 years; and
(c) Relay with soft iron magnetic structure shall be tested at least once every 2 years.
[49 FR 3384, Jan. 26, 1984]
§ 236.107 Ground tests.
(a) Except as provided in paragraph (b) of this section, a test for grounds on each energy bus furnishing power to circuits, the functioning of which affects the safety of train operation, shall be made when such energy bus is placed in service, and shall be made at least once every three months thereafter.
(b) The provisions of this rule shall not apply to track circuit wires, common return wires of grounded common single-break circuits, or alternating current power distribution circuits grounded in the interest of safety.
[49 FR 3384, Jan. 26, 1984]
§ 236.108 Insulation resistance tests, wires in trunking and cables.
(a) Insulation resistance of wires and cables, except wires connected directly to track rails, shall be tested when wires, cables, and insulation are dry. Insulation resistance tests shall be made between all conductors and ground, and between conductors in each multiple conductor cable, and between conductors in trunking, when wires or cables are installed and at least once every ten years thereafter.
(b) Then insulation resistance of wire or cable is found to be less than 500,000 ohms, prompt action shall be taken to repair or replace the defective wire or cable and until such defective wire or cable is replaced, insulation resistance test shall be made annually.
(c) In no case shall a circuit be permitted to function on a conductor having an insulation resistance to ground or between conductors of less than 200,000 ohms during the period required for repair or replacement.
[49 FR 3384, Jan. 26, 1984]
§ 236.109 Time releases, timing relays and timing devices.
Time releases, timing relays and timing devices shall be tested at least once every twelve months. The timing shall be maintained at not less than 90 percent of the predetermined time interval, which shall be shown on the plans or marked on the time release, timing relay, or timing device.
[49 FR 3384, Jan. 26, 1984]
§ 236.110 Results of tests.
(a) Results of tests made in compliance with §§236.102 to 236.109, inclusive; 236.376 to 236.387, inclusive; 236.576; 236.577; 236.586 to 236.589, inclusive; and 236.917(a) must be recorded on preprinted forms provided by the railroad or by electronic means, subject to approval by the FRA Associate Administrator for Safety. These records must show the name of the railroad, place and date, equipment tested, results of tests, repairs, replacements, adjustments made, and condition in which the apparatus was left. Each record must be:
(1) Signed by the employee making the test, or electronically coded or identified by number of the automated test equipment (where applicable);
(2) Unless otherwise noted, filed in the office of a supervisory official having jurisdiction; and
(3) Available for inspection and replication by FRA and FRA-certified State inspectors.
(b) Results of tests made in compliance with §236.587 must be retained for 92 days.
(c) Results of tests made in compliance with §236.917(a) must be retained as follows:
(1) Results of tests that pertain to installation or modification must be retained for the life-cycle of the equipment tested and may be kept in any office designated by the railroad; and
(2) Results of periodic tests required for maintenance or repair of the equipment tested must be retained until the next record is filed but in no case less than one year.
(d) Results of all other tests listed in this section must be retained until the next record is filed but in no case less than one year.
(e) Electronic or automated tracking systems used to meet the requirements contained in paragraph (a) of this section must be capable of being reviewed and monitored by FRA at any time to ensure the integrity of the system. FRA's Associate Administrator for Safety may prohibit or revoke a railroad's authority to utilize an electronic or automated tracking system in lieu of preprinted forms if FRA finds that the electronic or automated tracking system is not properly secured, is inaccessible to FRA, FRA-certified State inspectors, or railroad employees requiring access to discharge their assigned duties, or fails to adequately track and monitor the equipment. The Associate Administrator for Safety will provide the affected railroad with a written statement of the basis for his or her decision prohibiting or revoking the railroad from utilizing an electronic or automated tracking system.
[70 FR 11095, Mar. 7, 2005]
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