Federal Railroad Administration, DOT § 236.501 which display aspects with indications form to the requirements of this section on more favorable than ‘‘proceed at re- the effective date of this part into con- stricted speed’’ have been opened di- formity with this section in accordance with rectly or by shunting of track circuit. the following schedule: Not less than 33% during calendar year NOTE: Each carrier subject to this rule is 1984. hereby authorized to remove electrical or Not less than 66% during calendar year mechanical locks now installed within the 1985. purview of § 236.410 when either exception (1) The remainder during calendar year 1986. or (2) of the present rule is satisfied, subject to the condition that the following proce- [33 FR 19684, Dec. 25, 1968, as amended at 49 dures and actions be accomplished: FR 3386, Jan. 26, 1984] 1. Each carrier intending to remove a lock under the findings made herein and based on RULES AND INSTRUCTIONS the existence of one or more of the cir- cumstances as set forth in exception (1) or (2) § 236.426 Interlocking rules and in- as contained in the revised section, shall: structions applicable to traffic con- (a) Notify the FRA by letter setting forth trol systems. the location of the lock involved and the spe- The rules and instructions prescribed cific exception on which removal is based. (b) Include in the letter to the FRA an as- in §§ 236.327 and 236.328, § 236.330 to surance that the excepting circumstance re- § 236.334, inclusive, and § 236.342 shall lied upon will not be changed without either apply to traffic control systems. reinstallation of the electric or mechanical lock, or approval by the FRA of the changed INSPECTION AND TESTS circumstances. (c) Publish in its Time Table the not-to-ex- § 236.476 Interlocking inspections and ceed 20 miles per hour speed limit covering tests applicable to traffic control the area of the switch, when that is the ex- systems. ception relied upon; or, where exception (2) is relied upon, publish either in the Special In- The inspections and tests prescribed structions part of its Time Table or in sepa- in §§ 236.377 to 236.380, inclusive, and rate printed Special Instructions the loca- §§ 236.382, 236.383, and 236.386 shall apply tion of each hand-operated switch where to traffic control systems. electric or mechanical lock is removed and, where train movements are made in excess of [49 FR 3386, Jan. 26, 1984] twenty (20) miles per hour, concurrently issuing specific instructions, by stating Subpart E—Automatic Train Stop, therein, that trains are not to be permitted Train Control and Cab Signal to clear the main track at such switch. 2. Following the foregoing, and upon ac- Systems knowledgment of the letter to the FRA, such acknowledgment to be made promptly as an STANDARDS administrative action by the FRA’s Bureau of Railroad Safety, and such acknowledging § 236.501 Forestalling device and letter to be retained by the carrier as au- speed control. thority for the removal and as a record of (a) An automatic train stop system the exception on which relied, the lock may may include a device by means of then be removed. which the automatic application of the (c) Where a signal is used in lieu of brakes can be forestalled. electric or mechanical lock to govern (b) Automatic train control system movements from auxiliary track to shall include one or more of the fol- signaled track, the signal shall not dis- lowing features: play an aspect to proceed until after (1) Low-speed restriction, requiring the control circuits of signals gov- the train to proceed under slow speed erning movement on main track in ei- after it has either been stopped by an ther direction over the switch have automatic application of the brakes, or been opened, and either the approach under control of the engineman, its locking circuits to the switch are unoc- speed has been reduced to slow speed, cupied or a predetermined time inter- until the apparatus is automatically val has expired. restored to normal because the condi- NOTE: Railroads shall bring all hand-oper- tion which caused the restriction no ated switches that are not electrically or longer affects the movement of the mechanically locked and that do not con- train. 517 VerDate jul<14>2003 10:17 Oct 31, 2003 Jkt 200206 PO 00000 Frm 00517 Fmt 8010 Sfmt 8010 Y:\SGML\200206T.XXX 200206T § 236.502 49 CFR Ch. II (10–1–03 Edition) (2) Medium-speed restriction, requir- connected with the signal system that ing the train to proceed under medium the failure of the engineer to acknowl- speed after passing a signal displaying edge a restrictive wayside signal will an approach aspect or when approach- cause the intermittent inductive auto- ing a signal requiring a stop, or a stop matic train stop system to perform its indication point, in order to prevent an intended function. automatic application of the brakes. [49 FR 3386, Jan. 26, 1984] NOTE: Relief from the requirements of paragraphs (b) (1) and (2) of this section will § 236.505 Proper operative relation be- be granted, insofar as speed limits fixed by tween parts along roadway and definitions of Slow and Medium speeds are parts on locomotive. concerned, upon an adequate showing by an Proper operative relation between individual carrier where automatic train the parts along the roadway and the control systems now in service enforce speed restrictions higher than those required by parts on the locomotive shall obtain definitions in §§ 236.700 to 236.838 inclusive. under all conditions of speed, weather, wear, oscillation, and shock. (3) Maximum-speed restriction, ef- fecting an automatic brake application § 236.506 Release of brakes after auto- whenever the predetermined maximum matic application. speed limit is exceeded. The automatic train stop or train control apparatus shall prevent release § 236.502 Automatic brake application, initiation by restrictive block condi- of the brakes after automatic applica- tions stopping distance in advance. tion until a reset device has been oper- ated, or the speed of the train has been An automatic train-stop or train- reduced to a predetermined rate, or the control system shall operate to initiate condition that caused the brake appli- an automatic brake application at cation no longer affects the movement least stopping distance from the en- of the train. If reset device is used it trance to a block, wherein any condi- shall be arranged so that the brakes tion described in § 236.205 obtains, and cannot be released until the train has at each main track signal requiring a been stopped, or it shall be located so reduction in speed. that it cannot be operated by § 236.503 Automatic brake application; engineman without leaving his accus- initiation when predetermined rate tomed position in the cab. of speed exceeded. § 236.507 Brake application; full serv- An automatic train control system ice. shall operate to initiate an automatic The automatic train stop or train brake application when the speed of control apparatus shall, when operated, the train exceeds the predetermined cause a full service application of the rate as required by the setting of the brakes. speed control mechanism. § 236.508 Interference with application § 236.504 Operation interconnected of brakes by means of brake valve. with automatic block-signal system. The automatic train stop, train con- (a) A continuous inductive automatic trol, or cab signal apparatus shall be so train stop or train control system shall arranged as not to interfere with the operate in connection with an auto- application of the brakes by means of matic block signal system and shall be the brake valve and not to impair the so interconnected with the signal sys- efficiency of the brake system. tem as to perform its intended function in event of failure of the engineer to [49 FR 3386, Jan. 26, 1984] acknowledge or obey a restrictive way- side signal or a more restrictive cab § 236.509 Two or more locomotives signal. coupled. (b) An intermittent inductive auto- The automatic train stop, train con- matic train stop system shall operate trol or cab signal apparatus shall be ar- in connection with an automatic block ranged so that when two or more loco- signal system and shall be so inter- motives are coupled, or a pushing or 518 VerDate jul<14>2003 10:17 Oct 31, 2003 Jkt 200206 PO 00000 Frm 00518 Fmt 8010 Sfmt 8010 Y:\SGML\200206T.XXX 200206T Federal Railroad Administration, DOT § 236.529 helping locomotive is used, it can be § 236.515 Visibility of cab signals. made operative only on the locomotive The cab signals shall be plainly visi- from which the brakes are controlled. ble to member or members of the loco- motive crew from their stations in the § 236.510 [Reserved] cab. § 236.511 Cab signals controlled in ac- [49 FR 3386, Jan. 26, 1984] cordance with block conditions stopping distance in advance. § 236.516 Power supply. The automatic cab signal system Automatic cab signal, train stop, or shall be arranged so that cab signals train control device hereafter installed will be continuously controlled in ac- shall operate from a separate or iso- cordance with conditions described in lated power supply. § 236.205 that obtain at least stopping [49 FR 3386, Jan. 26, 1984] distance in advance. RULES AND INSTRUCTIONS; ROADWAY § 236.512 Cab signal indication when locomotive enters block where re- § 236.526 Roadway element not func- strictive conditions obtain. tioning properly. When a roadway element except The automatic cab signal system track circuit of automatic train stop, shall be arranged so that when a loco- train control or cab signal system is motive enters or is within a block, not functioning as intended, the signal wherein any condition described in associated with such roadway element § 236.205 obtains, the cab signals shall shall be caused manually to display its indicate ‘‘Proceed at Restricted most restrictive aspect until such ele- Speed.’’ ment has been restored to normal oper- ative condition.