The Board of Transport
Commissioners for Canada
Commission des Transports
du Canada

Order no. G.O. 602

Wednesday, the 5th of
March, A.D. 1941

In the matter of the application of the Railway Association of Canada for an Order amending the General Order of the Board No. 591, dated September 2, 1939, which authorizes for the observance of railway companies subject to the jurisdiction of the Board, regulations with regard to recommended practice for the prevention of electric sparks that may cause fire during the transfer of inflaynmable liquid between units of equipment operated on rails, or between equipment operated on rails and wayside piping, pumps, tanks, or other structures.

J. A. Cross
Chief Commissioner

Hugh Wardrope
Assistant Chief Commissioner

F. N. Garceau
Deputy Chief Commissioner

J. A. Stoneman
Commissioner

G. A. Stone
Commissioner

File no. 1717.73.1

Upon reading the application, and upon the report and recommendation of the Chief Engineer of the Board—

It is ordered:

  1. That the following regulations with regard to recommended practice for the prevention of electric sparks that may cause fire during the transfer of inflammable liquids, compressed inflammable gases or liquefied petroleum gases to or from rail equipment be, and they are hereby, authorized for the observance of railway companies subject to the jurisdiction of the Board, namely:—

    Definition

    An inflammable liquid, as defined by the Board, is any liquid which gives off inflammable vapours (as determined by the flash point from Tagliabue's open cup tester, as used for test of burning oils) at or below a temperature of 80° F.

    A compressed inflammable gas, or liquefied petroleum gas, is defined by the Board as any material with a gauge pressure exceeding 25 pounds per square inch at 70° F., or any liquid inflammable material having a Reid vapour pressure exceeding 40 pounds per square inch absolute at 100° F.

    Note.—The above definitions, together with a list of inflammable liquids, compressed inflammable gases or liquefied petroleum gases, and certain information pertaining thereto, are published in the Regulations for the Transportation of Explosives and Other Dangerous Articles by Freight authorized under the General Order of the Board No. 598, dated October 11, 1940, effective December 2, 1940.

    1. For all loading or unloading tracks—
      1. A permanent electrical connection shall be made between the rails on which rail equipment may stand and the piping system used in connection with the transfer of inflammable liquids, compressed inflammable gases, or liquefied petroleum gases. The electric connections shall be not less than one No. 4 nor less than two No. 6 AWG stranded copper, bronze, or copper-covered steel wire.
    2. For all loading or unloading tracks not equipped for electric operation where there is evidence of stray electric current—

      In addition to A (1) above, the following requirements shall be met:—

      1. The section of track on which any part of the rail equipment may stand while an inflammable liquid, compressed inflammable gas, or liquefied petroleum gas is being transferred shall be adequately bonded at each rail joint.
      2. Insulated rail joints shall be installed electrically to separate the loading or unloading track section from all other track rails. Such insulated rail joints shall not be bridged by rail equipment or other means during transfer operations.
      3. Other precautions, such as insulated joints in the permanent piping system, grounding, additional temporary bonds between the piping system and rail equipment tank, and other special measures as may be required under specific local conditions, shall be taken to provide adequate protection.
    3. For all loading or unloading tracks equipped for electric operation—

      In addition to A (1) and B (2) to (4) inclusive above, the following additional requirements shall be met:—

      1. An adequate return conductor shall be installed from the rails of the insulated track section through a switch which, when closed, short circuits the insulated track joints. This switch shall be interlocked with a switch controlling the supply of propulsion power to the contact conductor of the insulated track section in such a way that normally, when the return switch is open, the contact conductor of the insulated track section is de-energized and connected to the main track rail return. If the contact conductor of the insulated track section is a third rail, it may be grounded when de-energized, instead of being connected to the main track rail return.
      2. Where values of short circuit currents may be introduced at the transfer tracks that would set up differences of potential of a hazardous magnitude, it is recommended that special studies be made by qualified persons, and such additional or substitute measures taken as are necessary to provide adequate protection.
  2. 2. That the said General Order No. 591, dated September 2, 1939, be, and it is hereby, rescinded.

J. A. Cross
Chief Commissioner,
The Board of Transport Commissioners for Canada.