1. Every CTC Specification 112 and 114 tank car shall be equipped with double shelf couplers capable of sustaining, when coupled to any other cars, vertical loads of at least 90718.474 kg (200,000 pounds) applied in upward or downward directions in combination with buff loads of 907.185 kg (2,000 pounds), without disengagement or material failure.

• 2. (1) Every CTC Specification 112 and 114 tank car shall be equipped, at each end, with a tank head puncture resistance system comprising either a protective head shield or a full tank head jacket, enabling it to sustain, without loss of contents, coupler-to-tank head impacts with the area of the head shield as described in subsection (2) at relative car speeds of 28.968 km (18 miles) per hour when

  • (a) the weight of the impact tank car is at least 119294.793 kg (263,000 pounds);

  • (b) the impacted tank car is coupled to one or more “backup” cars that have a total weight of at least 217724.338 kg (480,000 pounds) and the hand brakes are applied on the first car; and

  • (c) the impacted tank car is pressurized to at least 689.746 kPa (100 psi).

• (2) The protective head shield shall

  • (a) be at least 12.7 mm (1/2 inch) thick and made from steel produced in accordance with Specifications A242, A572-GR50, A515-70 and A516-GR70 published by the ASTM or Specification TC-128B published by the AAR or any equivalent material approved by the Committee;

  • (b) be in the shape and size of the lower half of the head of the tank car or in the shape of a trapezoid with the following dimensions:

    • (i) a minimum width at the top of the centre sill of 1371.6 mm (four feet six inches), measured in a straight line between the extreme edges,

    • (ii) a minimum width at the top of the shield of 2743.2 mm (nine feet), measured in a straight line between the extreme edges and for cars with diameters less than 2743.2 mm (nine feet), the width of the shield must not extend beyond the outermost portion of the head and be not less than 76.2 mm (three inches) from the outermost point of the head,

    • (iii) the top corners of the shield rounded to a minimum radius of 228.6 mm (nine inches),

    • (iv) the bottom corners of the shield rounded to a minimum radius of 76.2 mm (three inches),

    • (v) all inside edges of the shield chamfered to a minimum of 3.175 mm (1/8 inch), and

    • (vi) a minimum height of 1371.6 mm (four feet six inches);

  • (c) be located so that the bottom of the shield touches the top of the centre sill;

  • (d) be shaped to the contour of the tank shell head, utilizing a minimum of three vertical bend lines;

  • (e) meet the impact test requirements of paragraph 24.5 in the “Specifications for Tank Car” Standard, effective October 1, 1972 published by the AAR, and, on testing, the protective head shield and its supporting structure

    • (i) shall not sustain visible permanent damage or deformation such as fractures, cracks, bends and dents, and

    • (ii) shall have adequate strength to remain attached and functionally unimpaired during the normal operations; and

  • (f) meet all of the workmanship requirements of the “Specifications for Design, Fabrication and Construction of Freight Cars” dated September 1, 1964 and published by the AAR.

• (3) The full tank head jacket shall be at least 12.7 mm (1/2 inch) thick and made from steel produced in accordance with Specifications A242, A 572-GR50, A 515-70 and A 516-GR70 published by the ASTM or Specification TC-128B published by the AAR or any equivalent material approved by the Committee.

• 3. (1) Every CTC Specification 112 and 114 tank car loaded with flammable gas shall be equipped with a thermal protection system that prevents the release of any of the car’s contents, except release through the safety relief valve, when subjected to

  • (a) a pool fire for 100 minutes; and

  • (b) a torch fire for 30 minutes.

• (2) The thermal protection system shall consist of

  • (a) a steel jacketed insulation, using a minimum of an 11-gauge steel jacket, except for the tank heads, that complies with the requirements of subsection 2(3); or

  • (b) a non-jacketed insulation system, applied in conjunction with the protective head shield described in subsection 2(2).

• 4. (1) Every CTC Specification 112 and 114 tank car shall be equipped with safety relief valves that meet the requirements of Appendix A of the 1977 Edition of the “Specification for Tank Cars” published by the AAR.

• (2) The relieving or discharge capacity of a tank shall be calculated in accordance with section A8.02 of Appendix A referred to in subsection (1), for compressed gases in non-insulated tanks.

5. Every CTC or DOT Specification 112 and 114 tank car that meets the requirements of these Regulations with respect to a tank head puncture resistance system and a thermal protection, shall be stencilled as follows:

• (a) when equipped with a thermal protection system enclosed in a steel jacket, the letter “J” shall be substituted for the letter “A” in the specification marking;

• (b) when equipped with a non-jacketed thermal protection system, the letter “T” shall be substituted for the letter “A” in the specification marking; and

• (c) when equipped with a tank head puncture resistance system with no thermal insulation and the tank car may be used in anhydrous ammonia service, the letter “S” shall be substituted for the letter “A” in the specification marking.