Selection and Use of Containers for the Handling, Offering for Transport, or Transporting of Dangerous Goods by Rail

10.1 Scope

This section applies to all containers handled, offered for transport or transported in Canada. Containers handled, offered for transport or transported from the United States to a place in Canada or through Canada to a destination in the United States may conform to the packaging and qualification requirements of Parts 172, 173, 179 and 180 of 49 CFR, except when subject to the terms of permits.

10.2 Selection and Use

10.2.1 General

A container must not be used in the handling, offering for transport, or transporting of dangerous goods unless Clause 4.4 or Schedules 1 and 2 of Appendix E specify that the container is permitted to contain the dangerous goods and the container and dangerous goods conform to all other applicable requirements set out in this standard. In the case of a tank car, the dangerous goods must be specified on the Certificate of Construction, Form AAR 4 2, or by addendum on Form R 1.

10.2.2 Due Date for Qualification

Unless otherwise specified in this standard:

  1. subject to clause 10.2.2 b., when a container is due for a qualification, the container must not be loaded; and
  2. when a container becomes due for a qualification after loading, unloading or during transport, the container must not be transported to one or more destinations, except for the purposes of unloading, cleaning and qualification.

10.2.3 Prohibition Against Old Ton Containers

A ton container that was manufactured before January 1, 1936, must not be used in the handling, offering for transport, or transporting of dangerous goods.

10.2.4 Localized dents and buckles

Except for dents or buckles that are in the heads of the tank car, a tank car that has a localized dent or buckle in its shell must not be used to handle, offer for transport or transport dangerous goods if:

  1. the localized dent or buckle in the tank shell has a depth greater than 19 mm (3/4 in.) at its deepest point, when that depth is measured relative to the surrounding un-deformed external surface of the tank shell; or
  2. any portion of the localized dent or buckle in the tank shell is within 610 mm (24 in.) of the longitudinal tank centre line at the bottom of the tank and the dent or buckle has a depth greater than 13 mm (1/2 in.) at its deepest point, when that depth is measured relative to the surrounding un-deformed external surface of the tank shell.

10.2.5 Minimum Test Pressure

10.2.5.1 A tank car or ton container must have a tank test pressure equal to or greater than the greatest of the following:

  1. 133% of the WP;
  2. 133% of the maximum loading or unloading pressure, whichever is greater;
  3. 20.7 bar (300 psi) for dangerous goods toxic by inhalation;
  4. The minimum test pressure for the specification in section 8 of this standard; and
  5. The minimum test pressure specified for the specific dangerous goods in the applicable special provision in Schedule 1 of Appendix E.

10.2.5.2 Higher Test Pressure

Unless otherwise specified in this standard, when a tank car or ton container with a given specification and tank test pressure is authorized, a tank car or ton container with the same specification and a higher marked tank test pressure may be used.

10.2.6 Air-enriched Mixture

Air pressure in excess of ambient atmospheric pressure must not be used to load or unload dangerous goods if this could create a flammable mixture within the vapour space of the container.

10.3 Safety Systems

10.3.1 Bottom-discontinuity Protection

10.3.1.1 General Requirement

Subject to clauses 10.3.1.2, 10.3.1.3 and 10.3.1.4, a tank car that is or may be used in the handling, offering for transport, or transporting of dangerous goods must be equipped with bottom-discontinuity protection that conforms to the requirements set out in paragraphs E9.0 and E10.0, of the AAR Specifications for Tank Cars publication.

10.3.1.2 Retrofit Requirement

For a tank car that is or may be used in the handling, offering for transport, or transporting of dangerous goods that was not required to be equipped with bottom-discontinuity protection before September 1, 1998 under the terms of Appendix Y of the AAR Specifications for Tank Cars publication, the tank car must conform to the bottom-discontinuity requirements set out in paragraphs E9.0 and E10.0, of the AAR Specifications for Tank Cars publication.

10.3.1.3 Old Protection Systems

For a tank car that is or may be used in the handling, offering for transport, or transporting of dangerous goods on which the bottom-discontinuity protection was modified before September 1, 1998, the tank car must conform to the bottom-discontinuity protection requirements set out in either Appendix Y or paragraphs E9.0 and E10.0 of the AAR Specifications for Tank Cars publication.

10.3.1.4 Exceptions

The requirements of this clause do not apply to tank cars built prior to 1979 transporting:

  1. UN2448, molten sulfur;
  2. UN3257, elevated temperature liquid, n.o.s.; or
  3. UN3258, elevated temperature solid, n.o.s.

10.3.2 Coupler Vertical Restraint System

A tank car that is or may be used in the handling, offering for transport, or transporting of dangerous goods by rail must be equipped with a coupler vertical restraint system that conforms to the requirements set out in clause 8.2.5.

10.3.3 Pressure-relief Devices on a Tank Car

Unless otherwise specified in this standard, a tank car must be equipped with one or more pressure-relief devices that conform to the requirements set out in clause 8.2.6.

10.3.3.1 Non-reclosing Prohibition

Subject to clauses 10.3.3.2, 10.3.3.3 and special provisions of Schedule 1 in Appendix E, in the case of a tank car is or may be used in the handling, offering for transport or transporting of dangerous goods that are classified as Division 6.1 Liquid, Packing Group I or II, Class 2 Gases, or Class 3 or 4 Liquids, the tank car must not be equipped with a non-reclosing pressure-relief device.

10.3.3.2 Exception re: Tank Car Manufactured Before 1991

If the dangerous goods are classified as a Division 6.1 Liquid or Class 4 Liquid and the liquid is not toxic by inhalation, a tank car that is equipped with a non-reclosing pressure-relief device and that was manufactured before 1991 may be used in the handling, offering for transport, or transporting of dangerous goods.

10.3.3.3 Exception re: Chloroprene

In the case of a shipment of chloroprene, inhibited, in a Specification 115 tank car, clause 10.3.3.1 does not apply.

10.3.3.4 Rupture Disc

The rupture disc of a non-reclosing pressure-relief device must not have an opening.

10.3.4 Tank-head Puncture-resistance System

A tank car that is or may be used in the handling, offering for transport, or transporting of Class 2 gases or that is manufactured from aluminum or nickel plate and is or may be used in the handling, offering for transport, or transporting of dangerous goods must have a tank-head puncture-resistance system installed that conforms to the requirements set out in clause 8.2.8 or to the corresponding requirements in effect at the time of installation.

10.3.5 Thermal Protection System

10.3.5.1 Application

Subject to clauses 9.5.10.1 and 10.3.5.2, a tank car that is or may be used in the handling, offering for transport, or transporting of Class 2 gases, other than cryogenic liquids, must have a thermal protection system that conforms to clause 8.2.7.

10.3.5.2 Exception for Some Insulated Tank Cars

Clause 10.3.5.1 does not apply in the case of a tank car for which this standard specifies that an insulation system having an overall thermal conductance equal to or less than 0.613 kJ/h m2 °C (0.03 Btu/h ft.2 °F) is required, and the tank car is equipped with the required system.

10.3.6 Safety Systems Delimiter

Unless otherwise specified in this standard, if this standard permits the use of a tank car with a specification delimiter that is:

  1. an "A", a tank car with an "S", a "T" or a "J" delimiter may be used;
  2. an "S", a tank car with a "T" or "J" delimiter may be used;
  3. a "T", a tank car with a "J" delimiter may be used; or
  4. a "J", only a tank car with a "J" delimiter may be used.

10.4 Loading Limits and Outage

10.4.1 Loading Limits

10.4.1.1 Application

A container must not be loaded with dangerous goods in excess of the loading limits specified in this standard or those otherwise applicable to the container.

10.4.1.2 Association of American Railroads Limit

Subject to clause 10.4.1.3, a tank car must not be loaded in excess of the total mass on rail limits per applicable axle size specified in the Field Manual of the Association of American Railroads Interchange Rules.

10.4.1.3 Post-1970 Manufacture

Except as otherwise provided in clauses 10.4.1.4, 10.4.1.5, 10.4.1.6, and 10.4.1.7, a tank car manufactured after November 30, 1970 must not be loaded in excess of the total mass on rail limits per applicable axle size specified in the Field Manual of the Association of American Railroads Interchange Rules or 119 297 kg (263 000 lb.) gross mass, whichever is less.

10.4.1.4 Increased Gross Masses

A Class DOT or TC 105, 111, 112, 113, 115, or 120 tank car with a steel tank car tank manufactured in accordance with par. 2.5 of the AAR Specifications for Tank Cars publication, may exceed 119 297 kg (263 000 lb.) gross mass, but may not exceed 129 727 kg (286 000 lb.) gross mass provided that:

  1. the tank capacity conforms to clause 8.2.4;
  2. the tank car is equipped with one or more pressure-relief devices conforming to clause 8.2.6. Reclosing pressure-relief devices must be used unless the tank car owner can demonstrate that the use of such a device decreases the level of safety below that afforded by a non-reclosing pressure-relief device; and
  3. the tank car conforms to all other applicable requirements of this standard, including qualification and maintenance.

10.4.1.5 AAR Tank Cars

A tank car with a carbon steel tank car tank permanently marked (i.e. stamped, etched, embossed or otherwise marked) to a TC 111 or DOT 111 specification and stencilled to an AAR 211 specification used in the handling, offering for transport, or transporting of dangerous goods referenced to Special Provision 2 or 67 may exceed 119 297 kg (263 000 lb.) gross mass, but may not exceed 129 717 kg (286 000 lb.) gross mass provided that:

  1. the tank capacity conforms to clause 8.2.4;
  2. the tank conforms to all other requirements of this standard applicable to the TC or DOT as-built specification with gross mass equal to or less than 119 297 kg (263 000 lb.), including qualification and maintenance;
  3. the tank car tank is manufactured from ASTM A516, Grade 70 material, or AAR TC-128, Grade B material;
  4. a non-jacketed tank car has a minimum shell and head thickness of 12.5 mm (½ in.) for ASTM A516, Grade 70 material, or 11.2 mm (7/16 in.) for AAR TC-128, Grade B material;
  5. a jacketed tank car has a minimum shell and head thickness of 11.2 mm (7/16 in.).;
  6. the tank car is equipped with one or more pressure-relief devices conforming to clause 8.2.6. Reclosing pressure-relief devices must be used unless the tank car owner can demonstrate that the use of such a device decreases the level of safety below that afforded by a non-reclosing pressure-relief device;
  7. the tank car meets all the requirements of AAR S-286;
  8. the tank car design meets all Road Environment Percent Occurrence Spectrum (REPOS) loading, including horizontal and vertical coupler loads, increased by a factor of 1.09 above the loading used for cars having a gross mass of 119 297 kg (263 000 lb.); and
  9. the tank car is subject to a Qualification and Maintenance Program that identifies the required inspection items, inspection methods, acceptance criteria and inspection frequencies and provides written procedures that ensure the work on the tank car conforms to the applicable regulations, industry and car owner's requirements.

10.4.1.6 Equivalency Certificates

A tank car that was previously authorized to exceed 119 297 kg (263 000 lb.), but not to exceed 129 717 kg (286 000 lb.) gross mass under equivalency certificates SR 4811, SR 4949, SR 5144, SR 5165, SR 5206, SR 5871, SR 6753, SR 7677, SR 7790, SR 8071, SR 8266, SR 8362, SR 8786, SR 8841, SR 9292, SR 9696, SR 10581, SR 10582, and SR 10668 may continue in service provided that:

  1. the tank car conforms to all the conditions specified in the most current revision of the applicable equivalency certificate and all other requirements of this standard applicable to tank cars with gross mass equal to or less than 119 297 kg (263 000 lb.), including qualification and maintenance; and
  2. the tank car is equipped with a pressure-relief device conforming to clause 8.2.6 and the pressure-relief device is installed as described in the document submitted to support the equivalency certificate application and on file with the Director.

10.4.1.7 Interim Tank Cars

A tank car conforming to specification 105J500I, 105J600I, 112J500I or to the alternatives authorized in clause 10.5.1.2 c. or special provision 83 must not exceed 129 725 kg (286 000 lb.) gross mass. Tank cars exceeding 119 297 kg (263 000 lb.) and up to 129 725 kg (286 000 lb.) gross mass must meet the requirements of AAR S-286.

10.4.2 Outage

10.4.2.1 Vacant Space for Outage

Vacant space must be left in the shell of the tank to provide the required outage.

10.4.2.2 Filling Limit

When a container is being filled with liquids, outage must be provided so that, under normal conditions of transport, including handling, no condition or release of dangerous goods that could endanger public safety occurs or may reasonably be expected to occur, including leakage or permanent distortion of the container, as a result of an expansion of the liquid.

10.4.2.3 Minimum Outage

Unless otherwise specified in this standard, for liquids and liquefied gases that are loaded into a container, the minimum outage must be:

  1. equal to or greater than 1% of the total capacity of a tank or a compartment of the tank at one of the following reference temperatures:
    1. 46.1°C (115°F) for a non-insulated tank;
    2. 43.3°C (110°F) for tanks having a thermal protection system incorporating a metal jacket that provides at 15.6°C (60°F) an overall thermal conductance equal to or less than 10.2 kJ/h m2 °C (0.50 Btu/h ft.2 °F); and
    3. 40.6°C (105°F) for an insulated tank conforming to Class 105, 115, 120 or to specification 111A100W3 or 111A100W4 when the overall thermal conductance is equal to or less than the minimum required of a Class 105 or 120.
  2. for dangerous goods toxic by inhalation, the outage must be equal to or greater than 5% of the total capacity of the tank or a compartment of the tank, at one of the following reference temperatures:
    1. 46.1°C (115°F) for a non-insulated tank;
    2. 43.3°C (110°F) for tanks having a thermal protection system incorporating a metal jacket that provides at 15.6°C (60°F) an overall thermal conductance equal to or less than 10.2 kJ/h m2 °C (0.50 Btu/h ft.2 °F); and
    3. 40.6°C (105°F) for an insulated tank conforming to Class 105, 115, 120.

10.5 Specific Dangerous Goods

10.5.1 Dangerous Goods Toxic by Inhalation

10.5.1.1 General Requirements

  1. A tank car that is or may be used in the handling, offering for transport, or transporting of dangerous goods toxic by inhalation must not have interior heater coils or bottom outlets.
  2. Unless otherwise specified in this standard, a tank car that is or may be used in the handling, offering for transport, or transporting of dangerous goods toxic by inhalation must have a tank test pressure of 20.7 bar (300 psi) or greater, a tank-head puncture-resistance system, and a metal jacket (e.g. 105S300W).

10.5.1.2 Tank Cars and Ton Containers for Dangerous Goods Toxic by Inhalation Other Than Class 2 Gases

  1. for tank cars built before the coming into force of this standard and for ton containers of any built date, the following conditions apply:
    1. dangerous goods that meet the criteria for Hazard Zone A must be handled, offered for transport or transported in tank cars or ton containers having a test pressure equal to or greater than 34.5 bar (500 psi) and conform to classes 105J, 106 or 110;
    2. dangerous goods that meet the criteria for Hazard Zone B must be handled, offered for transport or transported in tank cars or ton containers having a test pressure equal to or greater than 20.7 bar (300 psi) and conform to classes 105S, 106, 110, 112J, 114J or 120S;
    3. hydrogen fluoride, anhydrous must be handled, offered for transport or transported in tank cars or ton containers having a test pressure equal to or greater than 20.7 bar (300 psi) and conform to classes 105, 106, 110, 112, 114 or 120; and
    4. tank cars must have been approved by the Committee for specific dangerous goods toxic by inhalation or alterations and conversions documented for change of service to specific dangerous goods toxic by inhalation on the Certificate of Construction, Form AAR 4-2, or by addendum on Form R-1.
  2. Subject to clause c. tank cars built after the coming into force of this standard and that are or may be used in the handling, offering for transport, or transporting of dangerous goods toxic by inhalation set out in column 1 of the following table must conform to the applicable tank car specification set out in column 2 and, when applicable clauses 10.5.1.2.b. i. and ii.
Dangerous Goods Authorized Tank Car Specification
Acetone cyanohydrin, stabilized 105J500I
112J500I
Acrolein 105J600I
Allyl alcohol 105J500I
112J500I
Bromine or bromine solutions 105J500I
Chloropicrin 105J500I
112J500I
Chlorosulphonic acid 105J500I
112J500I
Dangerous goods toxic by inhalation, hazard zone A, not specifically identified in this table 105J600I
Dangerous goods toxic by inhalation, hazard zone B, not specifically identified in this table 105J500I
112J500I
Dimethyl sulphate 105J500I
112J500I
Ethyl chloroformate 105J500I
112J500I
Hexachlorocyclopentadiene 105J500I
112J500I
Hydrocyanic acid, aqueous solution or Hydrogen cyanide, aqueous solution, with not more than 20% hydrogen cyanide 105J500I
112J500I
Hydrogen cyanide, stabilized 105J600I
Hydrogen fluoride, anhydrous 105J500I
112J500I
Phosphorus trichloride 105J500I
112J500I
Sulphur trioxide, stabilized 105J500I
112J500I
Sulphuric acid, fuming, greater than or equal to 30% free sulphur trioxide 105J500I
112J500I
Titanium tetrachloride 105J500I
112J500I
  • i. Each tank car used for Acetone cyanohydrin, stabilized or Acrolein must have a reclosing pressure relief device having a start-to-discharge pressure of 10.3 bar (150 psi).
  • ii. Each tank car used for Hydrogen cyanide, stabilized or Hydrogen cyanide, aqueous solution, with not more than 20% hydrogen cyanide must have a reclosing pressure relief device having a start-to-discharge pressure of 15.5 bar (225 psi).
    • c. As an alternative to the authorized tank car specifications listed in the table in clause b. a tank car of the same specification but of the next lower test pressure, as prescribed in column 3 of the table in clause 8.3.22 may be used provided that both of the following conditions are met:
      • i. The difference between the alternative and the required minimum plate thicknesses, based on the calculation using the formula in clause 8.3.6.1, must be added to the alternative tank car jacket and head shield. When the jacket and head shield are made from steel with a minimum tensile strength from 70 000 psi to 81 000 psi, but the required minimum plate thickness calculation is based on steel with a minimum tensile strength of 81 000 psi, the thickness to be added to the jacket and head shield must be increased by a factor of 1.157. Forming allowances for heads are not required to be considered when calculating thickness differences; and
      • ii. The tank car jacket and head shields are manufactured from carbon steel plates as prescribed in clause 8.3.5.1. The steel must meet the Charpy requirements of par. 2.2.1.2 of the AAR Specifications for Tank Cars publication and head shields must be normalized after forming.
    • d. A higher test pressure is required if otherwise specified elsewhere in this standard.

10.5.1.3 Tank Cars for Dangerous Goods Toxic by Inhalation

  1. For tank cars built prior to the coming into force of this standard, tank cars must have been approved by the Committee for specific dangerous goods toxic by inhalation or alterations and conversions documented for change of service to specific dangerous goods toxic by inhalation on the Certificate of Construction, Form AAR 4-2, or by addendum on Form R-1.
  2. Each tank car manufactured after the coming into force of this standard and that is or may be used in the handling, offering for transport, or transporting dangerous goods toxic by inhalation must meet the applicable authorized tank car specification and standard listed in clauses 10.5.1.2 b. and 10.5.1.2 c. and Special Provisions 62, 64, 65, 80, 81, 82, or 83 of Schedule 1 of Appendix E.
  3. Each tank car meeting the applicable authorized tank car specification and standard listed in clauses 10.5.1.2 b. and 10.5.1.2 c. and Special Provisions 62, 64, 65, 80, 81, 82, or 83 of Appendix E, Schedule 1 is authorized for the transportation of dangerous goods toxic by inhalation for a period of 20 years after the date of original manufacture.
  4. A tank car owner retiring or otherwise removing a tank car from service transporting dangerous goods toxic by inhalation, other than because of damage to the tank car, must retire or remove a tank car manufactured of non-normalized steel in the head or shell before removing any tank car in service transporting dangerous goods toxic by inhalation manufactured of normalized steel meeting the applicable tank car specification.

10.5.1.4 Service Equipment Protection

  1. Each tank car manufactured after the coming into force of this standard for the transportation of dangerous goods toxic by inhalation must, in addition to the requirements prescribed in clause 8.2.3.2, enclose the service equipment within a protective housing and cover.
    1. Each tank car must be equipped with a protection system for service equipment and nozzle capable of sustaining, without failure, a rollover accident at a speed of 9 miles per hour, in which the rolling protective housing strikes a stationary surface assumed to be flat, level and rigid and the speed is determined as a linear velocity, measured at the geometric center of the loaded tank car as a transverse vector. Failure is deemed to occur when the deformed protective housing contacts any of the service equipment or when the lading retention capability is compromised.
    2. As an alternative to the tank car protective system for service equipment in clause i., the tank car may be equipped with a system that prevents the release of product from any of the top fittings in the case of an accident where any top fitting would be sheared off, and only internal, mechanically operated excess flow devices designed to remain closed during transportation are authorized. The tank nozzle must meet the performance standard in clause i.

10.5.1.5 Performance Requirement for Alternative Tank Car

An application for approval by the Committee of a tank car manufactured in accordance with the alternatives authorized in clause 10.5.1.2 c. or Special Provision 83 of Schedule 1 of Appendix E must include a demonstration through engineering analysis, that the tank jacket and support structure system, including any anchors and support devices, is capable of withstanding a 6 miles per hour coupling without jacket shift such that results in damage to the nozzle.

10.5.2 Assignment of Hazard Zones for Dangerous Goods Toxic by Inhalation

10.5.2.1 Division 2.3

For the purposes of this standard, the hazard zone of Class 2, Division 2.3 dangerous goods is assigned in Schedule 2 of Appendix E.

10.5.2.2 Liquid Dangerous Goods other than Class 2 gases

For the purposes of this standard, the hazard zone of liquid dangerous goods other than Class 2 gases is assigned in Schedule 2 of Appendix E.

10.5.2.3 Determination

  1. If Schedule 2 in Appendix E does not provide a hazard zone or provides more than one hazard zone for Class 2, Division 2.3 dangerous goods, or indicates that the hazard zone must be determined on the basis of the grouping criteria for Division 2.3, the hazard zone must be determined by applying the following criteria:
Hazard Zone Inhalation Toxicity
A LC50 less than or equal to 200 ppm
B LC50 greater than 200 ppm and less than or equal to 1000 ppm
C LC50 greater than 1000 ppm and less than or equal to 3000 ppm
D LC50 greater than 3000 ppm or less than or equal to 5000 ppm
  • b. If Schedule 2 in Appendix E does not provide a hazard zone or provides more than one hazard zone for liquid dangerous goods other than Class 2 gases, or indicates that the hazard zone must be determined, the hazard zone must be determined by applying the following criteria:
    1. Hazard Zone A: V≥500 LC50 and LC50 ≤200 mL/m3
    2. Hazard Zone B: V≥10 LC50 ; LC50 ≤1000 mL/m3; and the criteria for Hazard Zone A are not met.

Where V is the saturated vapor concentration in air of the material in mL/m3 at 20 °C and at 101.3 kPa.

10.5.3 Dangerous Goods in Packing Groups I or II Other Than Dangerous Goods Toxic by Inhalation

A class 111 tank car ordered after the date this standard comes into force by incorporation by reference in the TDG Regulations and used in the handling, offering for transport, or transporting of dangerous goods in packing groups I or II other than dangerous goods toxic by inhalation must conform to the following requirements:

10.5.3.1 Protection for service equipment on the top shell

The protective structure must be as tall as the tallest fitting involved and must provide protection for those fittings, without overstressing the tank shell and nozzles, when subjected to forces of 1/2W in the vertical downward direction, 1W horizontal in the longitudinal direction, and 1/2W horizontal in the lateral direction, where:

  1. W is defined as the designed gross rail load of the tank car, less trucks, with a minimum value of 286 000 lb.;
  2. The forces are applied separately and uniformly over the projected plane of the protective structure perpendicular to the direction of the force;
  3. For horizontal loads, the projected plane extends from the top of the tank to the top of the protective structure;
  4. In the case of multiple nozzles:
    1. The forces are applied uniformly over their combined projected area if the reinforcement zones of the nozzle, as defined in par. E3.3.1, of the AAR Specifications for Tank Cars publication, have a positive overlap; and
    2. If there is no overlap of the reinforcement zones, each nozzle must be protected so that it can withstand the applied loads independent of the other nozzles;
  5. Calculations must use the minimum specified tensile strength of the material for the tank, nozzle(s), unprotected service equipment, and protective device (where applicable); and
  6. Stresses must not exceed the critical buckling stress of the assembly under consideration.

10.5.3.1.1 The design stresses must not exceed the minimum specified tensile stress for the tank, nozzle, and protective housing, provided that the critical buckling stresses are not exceeded.

10.5.3.1.2 The protective structure must not reduce the pressure relief device flow capacity below the minimum required.

10.5.3.1.3 The protective structure must provide a means of drainage with a minimum flow area equivalent to six 1-in. diameter holes (4.71 in2)

10.5.3.1.4 The strength of the attachment of the protective structure to its base structure must not exceed 70 percent of the attachment strength of the base structure to its base structure. For example, if the protective structure is attached to the nozzle, the strength of the attachment of the protective structure to the nozzle must not exceed 70 percent of the strength of the attachment of the nozzle to the tank.

10.5.3.1.5 Individual fittings may be unprotected if there is no loss of lading when subjected to the design loads in clause 10.5.3.1.1. If unprotected fittings are used in conjunction with a protective structure, the design loads are shared in proportion to the projected area of the protective structure and the fittings.

10.5.3.1.6 Discontinuity protection is not required for manway covers that have internal or external shear rings designed to resist the horizontal loads defined in clause 10.5.3.1.1.

10.5.3.1.7 No discontinuity protection is required for internal pressure relief devices, cover plates, blind flanges, or plugs.

10.5.3.2 Pressure-Relief Devices

Subject to clause 10.5.3.2.2 the tank car must be equipped with one or more reclosing pressure-relief devices conforming to clause 8.2.6. A non-reclosing pressure relief device is authorized if the tank car owner can demonstrate that the use of such a device increases the level of safety above that afforded by a reclosing pressure-relief device.

10.5.3.2.1 When the tank car is used for Petroleum Crude Oil, UN 1267 or Ethanol Gasoline Mixtures, UN 3475 it must be equipped with one or more reclosing pressure relief devices with a start-to-discharge pressure of 75 psi and a minimum total relieving capacity of 27 000 scfm.

10.5.3.3 Tank material and Thickness

Subject to clause 10.5.3.3.2 the tank car must have heads and shell manufactured of normalized TC128 grade B steel or normalized A516-70 steel. Tank car heads must be normalized after forming unless the Committee specifically approved otherwise. For tanks manufactured of normalized TC128 Grade B steel, non-jacketed tanks must be at least ½ in. thick and jacketed tanks must be at least 7/16 in. thick. For tanks manufactured of normalized A516-70 steel, non-jacketed tanks must be at least 9/16 in. thick and jacketed tanks must be at least ½ in. thick. In all cases the tank car must be equipped with at least ½ in. half head shields In the case where the tank car has heads and shell of high-alloy steel the heads and shell must be at least ½ in. thick and be equipped with at least ½ in. half-head shields if not jacketed. Jacketed tanks must be at least 7/16 in. thick and be equipped with ½ in. thick jacket heads at a minimum.

10.5.3.4 Fatigue Design Loads

All road environment percent occurrence spectrum (REPOS) loads, including horizontal and vertical coupler loads, used for fatigue calculations must be increased by a factor of at least 1.09 above the loads used for tank cars with a maximum gross rail load of 263 000 lb.

10.5.3.5 S-286

The tank car must meet all the requirements of AAR S-286.

10.5.4 Cryogenic Liquids

The interior of the inner tank of a cryogenic liquid tank car and all connecting lines must be thoroughly cleaned, dried, and protected from further contamination before their first use.

10.5.5 Liquefied Petroleum Gas and Anhydrous Ammonia

10.5.5.1 Leaking

A tank car used in the transportation of liquefied petroleum gas or anhydrous ammonia must not leak.

10.5.5.2 Definition of Leaking in Transportation

In the case of a tank car in transportation and for the purposes of emissions of liquefied petroleum gas or anhydrous ammonia from inside the protective housing or the joint between the manway nozzle and the manway cover, leaking is defined as set out in Appendix A and Appendix B, respectively.

10.5.5.3 Leaking Tank Car in Transportation

If the liquefied petroleum gas or anhydrous ammonia tank car is leaking in transportation, the source of the emissions must be investigated and corrective action must be taken to stop or reduce the leaking.

10.6 Loading and Unloading Railway Vehicles

10.6.1 Prohibition Against Movement

During the period of time when dangerous goods are being loaded into or onto a railway vehicle or unloaded from a railway vehicle, that railway vehicle and any railway vehicle to which it is attached must not be moved.

10.6.2 Conditions

Dangerous goods must not be loaded into or onto a railway vehicle or unloaded from a railway vehicle unless the following requirements are met. Except for clauses c. and d. the following requirements do not apply to a railway vehicle that is a boxcar or a flatcar:

  1. in the case of dangerous goods having a primary or subsidiary classification of 2.1, 3, 4, or 5 measures are taken to prevent exposure of the dangerous goods to a source of ignition, intense heat, or any source of electrical hazard and to dissipate static electricity and in the case of a tank car ensuring grounding of the tank car tank is achieved before any service equipment is opened and remains effective until the loading or unloading is completed or discontinued and all service equipment has been closed and secured;
  2. the railway vehicle or coupled string of railway vehicles is immobilized. As a minimum, the hand brakes must be applied and at least one wheel must be blocked in both directions on at least:
    1. one car for a one or two car coupled string; or
    2. two cars for a three to nine car coupled string plus one additional car for every block and any fraction of block of ten cars in excess of the first nine cars in the coupled string, including the first and last cars of the string;
  3. the section of track where the loading or unloading takes place is protected by locked switches, or locked derails that are controlled by the loading or unloading facility;
  4. caution signs that conform to the requirements set out in clause 10.6.3 are conspicuously displayed on the section of track or on the railway vehicle to warn approaching railway vehicle operators that loading or unloading operations are in progress;
  5. the immediate vicinity of the railway vehicle is kept substantially free of combustible materials or other materials that are not compatible with the dangerous goods being loaded or unloaded;
  6. in the case of a tank car, the loading and unloading components and the connections, when required, made between the tank car and the first fixed process isolation valve prevent any release of dangerous goods;
  7. in the case of a tank car, when the loading or unloading is completed all closures are secured, the connections made between the tank car service equipment and the loading or unloading components are disconnected, except that the heater coil inlet and outlet pipes may be left open after unloading;
  8. in the case when the loading is discontinued a tank car may stand with loading connections attached provided the tank car shutoff valves and facility first fixed process isolation valve, when so equipped are secured in the closed position and all other conditions of clause 10.6.2 are met, including clause 10.6.2 i.
  9. the railway vehicle is monitored by direct, remote, or automatic means during loading or unloading so that any condition or release of dangerous goods from the railway vehicle that could endanger public safety can be promptly identified, and remedied; and
  10. in the case of tank cars that are equipped with interconnecting pipes measures are taken to ensure no appreciable amount of liquid dangerous goods remain in the interconnecting pipes after the loading or unloading operation is completed.

10.6.3 Caution Signs

Caution signs must be manufactured of metal or other durable material and having dimensions equal to or greater than 30 x 38 cm (12 x 15 in.) and bear the words "STOP" or "ARRÊT" in white capital letters equal to or greater than 10 cm (4 in.) in height on a blue background.

10.7 Loading of Containers

10.7.1 Before Loading

Dangerous goods must not be loaded into a container if any one of the following conditions exists:

  1. The container does not conform to the requirements for selection and use set out in this standard, including clause 4.4 and Appendix E;
  2. The container is due for a qualification;
  3. The material used to manufacture the container or the lining or coating is not compatible with the dangerous goods;
  4. The container already contains dangerous goods or other substances that could react with the dangerous goods to be loaded, and the reaction may reasonably be expected to cause, under normal conditions of transport, including handling, a condition or release of dangerous goods that could endanger public safety; or
  5. The dangerous goods are at a temperature outside the design temperature range of the container or outside the service temperature range of the lining or coating.

10.7.2 During Loading

During the period of time that a tank car equipped with:

  1. bottom discharge outlets is being loaded:
    1. the caps of the outlets must be removed;
    2. the plugs of the caps of the outlets must be opened; or
    3. the plugs and secondary valves must be opened; and
    4. the loading must be stopped if any release of dangerous goods occurs.
  2. interior heater coils is being loaded, except when the inlet and outlet of the coils are blocked off and the coils are rendered inoperative, the cap of the heater coil inlet and outlet must be removed and the loading must be stopped if any release of dangerous goods occurs.

10.7.3 Containers Loaded on or into a Railway Vehicle

If a container is loaded on or into a railway vehicle, the container must be designed, manufactured, qualified, maintained, and secured so that, under normal condition of transport, including handling:

  1. there is no noticeable movement of the container relative to the railway vehicle or damage to the means of securement; and
  2. no condition or release of dangerous goods that could endanger public safety occurs or may reasonably be expected to occur, including any visible damage or deformation to the railway vehicle or container that affects the structural integrity or dangerous goods retention capability of the railway vehicle or container.

10.8 Before Offering for Transport

10.8.1 Requirements

A person who offers for transport a container containing dangerous goods must:

  1. conduct an external visual inspection that conforms to the requirements set out in clause 10.8.2;
  2. make a determination that the container is in proper condition and the dangerous goods are safe for transportation; and
  3. ensure that action is taken to remedy any release or problem discovered during the visual inspection or condition that could endanger public safety, including action relating to a condition, problem or release that requires repair or replacement of the container or removal of the dangerous goods.

10.8.2 External Visual Inspection

As a minimum, the external visual inspection of the container must include:

  1. except where insulation or a thermal protection system precludes an inspection without removing insulation or jacketing, inspecting the shell of the container, and heads for any condition that could endanger public safety, including evidence of abrasion, cracks, dents, distortions, defects in welds, corrosion, damage, or missing or loose bolts and nuts;
  2. inspecting, to the extent practicable, for corrosion or damage to and for serviceability of all closures of openings and service equipment or parts thereof, including gaskets, ensuring that any component or part thereof that does not conform to the requirement of this standard is repaired or replaced;
  3. ensuring that all closures of openings including fill hole covers, manway covers and outlet valve caps, protective housings and covers, and all fasteners securing them on a container, are in good condition and secured by the use of suitable tools as required to achieve conformance with clause 4.10.2 and, in the case of threaded closures, that minimal amounts of thread sealing materials are used;
  4. inspecting for any spillage of the dangerous goods on the exterior surface of the container and ensuring that any spillage is removed, with the exception of dried residue of molten sulphur on tank cars in amounts described as acceptable until next shopping in the Sulphur Institute "Molten Sulphur Rail Tank Car Guidance" document;
  5. except on tank cars used in the handling, offering for transport, or transporting of Class 2 gases or tank cars being returned after unloading, inspecting pressure-relief devices, including the removal and inspection of rupture discs on safety vents, for any condition that could alter the intended operation of the device or endanger public safety, including corrosion or damage. As an alternative to the removal of rupture discs, the person conducting the inspection must make a determination that the rupture discs are not ruptured and must provide documentary evidence that:
    1. the dangerous goods being transported are compatible with and have not corroded the rupture discs; and
    2. measures have been taken to prevent the blocking or restraining of the safety vent approach channel by foreign objects;
  6. for a combination pressure-relief device incorporating a rupture disc, inspecting and opening each detection device including a needle valve, trycock or telltale indicator to ensure the integrity of the rupture disc;
  7. inspecting to the extent practicable the thermal protection system, tank-head puncture-resistance system, coupler vertical restraint system, and bottom-discontinuity protection for any condition that could endanger public safety;
  8. inspecting the markings on the container for correctness, adequacy and legibility; and
  9. inspecting the external surface of ceramic type filters on tank cars equipped with a venting device and transporting hydrogen peroxide, aqueous solution with more than 40% hydrogen peroxide, stabilized, except on tank cars being returned after unloading.

10.9 Before Transporting

Before transporting a container containing dangerous goods, the person who will be transporting the container must conduct an external visual inspection of the container, to the extent practicable, from ground level and ensure that:

  1. required placards are in place and in conformance;
  2. closures of openings are in good condition and secured; and
  3. action is taken to remedy any release or condition that could endanger public safety, including action relating to a condition or release that requires repair or replacement of the container or removal of the dangerous goods.

10.10 Rail Operating Restrictions

10.10.1 Highway Tanks and Tube Trailers

Highway tanks and tube trailers may be transported on railway vehicles if the rail destination is in a remote area not accessible by road, and provided all applicable conditions of clauses 10.10.1 a. and 10.10.1 b. are complied with;

  1. Highway Tanks — The transportation of highway tanks on railway vehicles must conform to the following applicable conditions:
    1. the dangerous goods are in Class 3, 8 or 9;
    2. the tank and any compartment of the tank contain a volume of liquid dangerous goods that is equal to or less than 5% of the tank or compartment's volumetric capacity respectively;
    3. the highway tank is selected and used in accordance with the requirements of the standard CSA B621, except that the use of non-specification highway tanks is not authorized;
    4. in the case of a DOT 306 or TC 306 highway tank, the manhole cover assemblies meet or exceed the requirements of either CSA B620, clause 5.6.6, or US 49 CFR, par. §178.345-5;
    5. in the case of a tank truck, the tank truck is secured to the railway vehicle in accordance with the requirements of AAR Open Top Loading Rules Manual for Four or six wheel truck or other motor vehicle;
    6. in the case of a tank trailer, the forward end of the trailer is secured to the railway vehicle with an AAR approved intermodal trailer hitch, the rail carrier personnel has verified that the king pin of the trailer is engaged and locked in the trailer hitch, the rear end is secured in accordance with the requirements of the AAR Open Top Loading Rules Manual for Trailers, all types and the landing gear and bumper are not used for securing the trailer to the railway vehicle;
    7. in the case of a tank trailer transported with its tractor, the tractor is transported on a separate railway vehicle;
    8. before the person responsible for the road transport of the dangerous goods releases the highway tank to the rail carrier, that person inspects the attachment points of the tank to the truck or trailer frame to detect any condition that may compromise the integrity of the securement of the tank to the frame, ensure that the highway tank has all valves and closures, at the exclusion of the pressure-relief device, securely closed and capped as applicable, and reports the results of this inspection and this verification to the rail carrier; and
    9. the railway vehicle on which the highway tank is transported is separated by at least one railway vehicle from a railway vehicle for which a placard is required to be displayed in accordance with Part 4 of the TDG Regulations, is separated by at least five railway vehicles from the locomotive and is located at the tail end or as close as possible to the tail end of the train and behind any loaded railway vehicle.
  2. Tube Trailers — The transportation of tube trailers on railway vehicles must conform to the following applicable conditions:
    1. the dangerous goods must be Class 2.1 or 2.2;
    2. the tubes are selected, maintained, and used in accordance with CSA B340 or CSA B342; and
    3. conform to clause 10.10.1 a. vi, vii, viii with the exception of the need to cap service equipment, and ix.

10.10.2 Transportation of Dangerous Goods in or on Hi-rail Equipment

Tank trucks transporting Class 2 gases or Class 3 flammable liquids must comply with the requirements of CSA B621 or CSA B622, be properly secured, filled, and closed so that during the course of normal transportation, there will be no release of dangerous goods that could endanger public safety; and:

  1. the hi-rail vehicle equipment is authorized by the operating railway, and is not physically connected to any other railway vehicle; and
  2. the hi-rail vehicle must be in the control of a railway employee qualified under the Canadian Rail Operating Rules.

10.10.3 Handling of Tank Cars Conforming to Specification 113 and AAR 204W

A tank car conforming to Specification 113 and AAR 204W must not be:

  1. uncoupled while in motion;
  2. coupled into with more force than is necessary to complete the coupling; or
  3. struck by any railway vehicle moving under its own motion.

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