[Code of Federal Regulations]

[Title 49, Volume 2]

[Revised as of October 1, 2005]

From the U.S. Government Printing Office via GPO Access

[CITE: 49CFR173.31]



[Page 450-454]

 

                        TITLE 49--TRANSPORTATION

 

   CHAPTER I--PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, 

                      DEPARTMENT OF TRANSPORTATION

 

PART 173_SHIPPERS_GENERAL REQUIREMENTS FOR SHIPMENTS AND PACKAGINGS

--Table of Contents

 

     Subpart B_Preparation of Hazardous Materials for Transportation

 

Sec. 173.31  Use of tank cars.



    (a) General. (1) No person may offer a hazardous material for 

transportation in a tank car unless the tank car meets the applicable 

specification and packaging requirements of this subchapter or, when 

this subchapter authorizes the use of an non-DOT specification tank car, 

the applicable specification to which the tank was constructed.

    (2) Tank cars and appurtenances may be used for the transportation 

of any commodity for which they are authorized in this part and 

specified on the certificate of construction (AAR Form 4-2 or by 

addendum on Form R-1). See Sec. 179.5 of this subchapter. Transfer of a 

tank car from one specified service on its certificate of construction 

to another may be made only by the owner or with the owner's 

authorization. A tank car proposed for a commodity service other than 

specified on its certificate of construction must be approved for such 

service by the AAR's Tank Car Committee.

    (3) No person may fill a tank car overdue for periodic inspection 

with a hazardous material and then offer it for transportation. Any tank 

car marked as meeting a DOT specification and any non-specification tank 

car transporting a hazardous material must have a periodic inspection 

and test conforming to subpart F of part 180 of this subchapter.

    (4) No railroad tank car, regardless of its construction date, may 

be used for the transportation in commerce of any hazardous material 

unless the air brake equipment support attachments of such tank car 

conform to the standards for attachments set forth in Sec. Sec. 

179.100-16 and 179.200-19 of this subchapter.

    (5) No railroad tank car, regardless of its construction date, may 

be used for the transportation in commerce of any hazardous material 

with a self-energized manway located below the liquid level of the 

lading.

    (6) Unless otherwise specifically provided in this part:

    (i) When the tank car delimiter is an ``A,'' offerors may also use 

tank cars with a delimiter ``S,'' ``J'' or ``T''.

    (ii) When the tank car delimiter is an ``S,'' offerors may also use 

tank cars with a delimiter ``J'' or ``T''.

    (iii) When a tank car delimiter is a ``T'' offerors may also use 

tank cars with a delimiter of ``J''.

    (iv) When a tank car delimiter is a ``J'', offerors may not use a 

tank car with any other delimiter.

    (7) A class DOT-103 or DOT-104 tank car may continue to be used for 

the transportation of a hazardous material if it meets the requirements 

of this subchapter and the design requirements in Part 179 of this 

subchapter in effect on September 30, 2003; however, no new construction 

is authorized.

    (b) Safety systems--(1) Coupler vertical restraint. Each tank car 

conforming to a DOT specification and any other tank car used for 

transportation of a hazardous material must be equipped with a coupler 

vertical restraint system that meets the requirements of Sec. 179.14 of 

this subchapter.

    (2) Pressure relief devices. (i) Pressure relief devices on tank 

cars must conform to part 179 of this subchapter.

    (ii) A single-unit tank car transporting a Division 6.1 PG I or II, 

or Class 2, 3, or 4 material must have a reclosing pressure relief 

device. However, a single-unit tank car built before January 1, 1991, 

and equipped with a non-reclosing pressure relief device may be used to 

transport a Division 6.1 PG I or II material or a Class 4 liquid 

provided



[[Page 451]]



such materials do not meet the definition of a material poisonous by 

inhalation.

    (3) Tank-head puncture-resistance requirements. The following tank 

cars must have a tank-head puncture-resistance system that conforms to 

the requirements in Sec. 179.16 of this subchapter, or to the 

corresponding requirements in effect at the time of installation:

    (i) Tank cars transporting a Class 2 material.

    (ii) Tank cars constructed from aluminum or nickel plate that are 

used to transport hazardous material.

    (iii) Except as provided in paragraph (b)(3)(iv) of this section, 

those tank cars specified in paragraphs (b)(3)(i) and (ii) of this 

section not requiring a tank-head puncture resistance system prior to 

July 1, 1996, must have a tank-head puncture resistance system installed 

no later than July 1, 2006.

    (iv) Class DOT 105A tank cars built prior to September 1, 1981, 

having a tank capacity less than 70 kl (18,500 gallons), and used to 

transport a Division 2.1 (flammable gas) material, must have a tank-head 

puncture-resistant system installed no later than July 1, 2001.

    (4) Thermal protection requirements. The following tank cars must 

have thermal protection that conforms to the requirements of Sec. 

179.18 of this subchapter:

    (i) Tank cars transporting a Class 2 material, except for a class 

106, 107A, 110, and 113 tank car. A tank car equipped with a thermal 

protection system conforming to Sec. 179.18 of this subchapter, or that 

has an insulation system having an overall thermal conductance of no 

more than 0.613 kilojoules per hour, per square meter, per degree 

Celsius temperature differential (0.03 B.t.u. per square foot, per hour, 

per degree Fahrenheit temperature differential), conforms to this 

requirement.

    (ii) A tank car transporting a Class 2 material that was not 

required to have thermal protection prior to July 1, 1996, must be 

equipped with thermal protection no later than July 1, 2006.

    (5) Bottom-discontinuity protection requirements. No person may 

offer for transportation a hazardous material in a tank car with bottom-

discontinuity protection unless the tank car has bottom-discontinuity 

protection that conforms to the requirements of E9.00 and E10.00 of the 

AAR Specifications for Tank Cars (IBR, see Sec. 171.7 of this 

subchapter). Tank cars not requiring bottom-discontinuity protection 

under the terms of Appendix Y of the AAR Specifications for Tank Cars as 

of July 1, 1996, must conform to these requirements no later than July 

1, 2006, except that tank cars transporting a material that is hazardous 

only because it meets the definition of an elevated temperature material 

or because it is molten sulfur do not require bottom discontinuity 

protection.

    (6) Scheduling of modifications and progress reporting. The date of 

conformance for the continued use of tank cars subject to paragraphs 

(b)(3), (b)(4), (b)(5), (e)(2), and (f) of this section and Sec. Sec. 

173.314(j) and 173.323(c)(1) is subject to the following conditions and 

limitations.

    (i) Each tank car owner shall modify, reassign, retire, or remove at 

least 50 percent of their in-service tank car fleet within the first 

half of the compliance period and the remainder of their in-service tank 

car fleet during the second half of the compliance period.

    (ii) By October 1 of each year, each owner of a tank car subject to 

this paragraph (b)(6) shall submit to the Federal Railroad 

Administration, Hazardous Materials Division, Office of Safety Assurance 

and Compliance, 1120 Vermont Avenue, Mail Stop 25, Washington, DC 20590, 

a progress report that shows the total number of in-service tank cars 

that need head protection, thermal protection, or bottom-discontinuity 

protection; the number of new or different tank cars acquired to replace 

those tank cars required to be upgraded to a higher service pressure; 

and the total number of tank cars modified, reassigned, acquired, 

retired, or removed from service the previous year.

    (c) Tank car test pressure. A tank car used for the transportation 

of a hazardous material must have a tank test pressure equal to or 

greater than the greatest of the following:



[[Page 452]]



    (1) Except for shipments of carbon dioxide, anhydrous hydrogen 

chloride, vinyl fluoride, ethylene, or hydrogen, 133 percent of the sum 

of lading vapor pressure at the reference temperature of 46 [deg]C (115 

[deg]F) for non-insulated tank cars or 41 [deg]C (105 [deg]F) for 

insulated tank cars plus static head, plus gas padding pressure in the 

vacant space of a tank car;

    (2) 133 percent of the maximum loading or unloading pressure, 

whichever is greater;

    (3) 20.7 Bar (300 psig) for materials that are poisonous by 

inhalation (see Sec. 173.31(e)(2)(ii) for compliance dates);

    (4) The minimum pressure prescribed by the specification in part 179 

of this subchapter; or

    (5) The minimum test pressure prescribed for the specific hazardous 

material in the applicable packaging section in subpart F or G of this 

part.

    (d) Examination before shipping. (1) No person may offer for 

transportation a tank car containing a hazardous material or a residue 

of a hazardous material unless that person determines that the tank car 

is in proper condition and safe for transportation. As a minimum, each 

person offering a tank car for transportation must perform an external 

visual inspection that includes:

    (i) Except where insulation or a thermal protection system precludes 

an inspection, the tank shell and heads for abrasion, corrosion, cracks, 

dents, distortions, defects in welds, or any other condition that makes 

the tank car unsafe for transportation;

    (ii) The piping, valves, fittings, and gaskets for corrosion, 

damage, or any other condition that makes the tank car unsafe for 

transportation;

    (iii) For missing or loose bolts, nuts, or elements that make the 

tank car unsafe for transportation;

    (iv) All closures on tank cars and determine that the closures and 

all fastenings securing them are properly tightened in place by the use 

of a bar, wrench, or other suitable tool;

    (v) Protective housings for proper securement;

    (vi) The pressure relief device, including a careful inspection of 

the rupture disc in non-reclosing pressure relief devices, for corrosion 

or damage that may alter the intended operation of the device;

    (vii) Each tell-tale indicator after filling and prior to 

transportation to ensure the integrity of the rupture disc;

    (viii) The external thermal protection system, tank-head puncture 

resistance system, coupler vertical restraint system, and bottom 

discontinuity protection for conditions that make the tank car unsafe 

for transportation;

    (ix) The required markings on the tank car for legibility; and

    (x) The periodic inspection date markings to ensure that the 

inspection and test intervals are within the prescribed intervals.

    (2) Closures on tank cars are required, in accordance with this 

subchapter, to be designed and closed so that under conditions normally 

incident to transportation, including the effects of temperature and 

vibration, there will be no identifiable release of a hazardous material 

to the environment. ln any action brought to enforce this section, the 

lack of securement of any closure to a tool-tight condition, detected at 

any point, will establish a rebuttable presumption that a proper 

inspection was not performed by the offeror of the car. That presumption 

may be rebutted by any evidence indicating that the lack of securement 

resulted from a specific cause not within the control of the offeror.

    (e) Special requirements for materials poisonous by inhalation--(1) 

Interior heater coils. Tank cars used for materials poisonous by 

inhalation may not have interior heater coils.

    (2) Tank car specifications. A tank car used for a material 

poisonous by inhalation must have a tank test pressure of 20.7 Bar (300 

psig) or greater, head protection, and a metal jacket (e.g., DOT 

105S300W), except that--

    (i) A higher test pressure is required if otherwise specified in 

this subchapter; and

    (ii) Other than as provided in paragraph (b)(6) of this section, a 

tank car which does not conform to the requirements of this paragraph 

(e)(2), and was authorized for the material poisonous by inhalation 

under the regulations in



[[Page 453]]



effect on June 30, 1996, may continue in use until July 1, 2006.

    (f) Special requirements for hazardous substances. (1) A tank car 

used for a hazardous substance listed in paragraph (f)(2) of this 

section must have a tank test pressure of at least 13.8 Bar (200 psig), 

head protection and a metal jacket, except that--

    (i) No metal jacket is required if--

    (A) The tank test pressure is 23.4 Bar (340 psig) or higher; or

    (B) The tank shell and heads are manufactured from AAR steel 

specification TC-128, normalized;

    (ii) A higher test pressure is required if otherwise specified in 

this subchapter; and

    (iii) Other than as provided in paragraph (b)(6) of this section, a 

tank car which does not conform to the requirements of this paragraph 

(f)(1), and was authorized for a hazardous substance under the 

regulations in effect on June 30, 1996, may continue in use until July 

1, 2006.

    (2) List of hazardous substances. Hazardous substances for which the 

provisions of this paragraph (f) apply are as follows:



Aldrin

Allyl chloride

alpha-BHC

beta-BHC

delta-BHC

gamma-BHC

Bis(2-chloroethyl) ether

Bromoform

Carbon tetrachloride

Chlordane

p-Chloroaniline

Chlorobenzene

Chlorobenzilate

p-Chloro-m-cresol

2-Chloroethyl vinyl ether

Chloroform

2-Chloronapthalene

o-Chlorophenol

3-Chloropropionitrile

DDE

DDT

1,2-Dibromo-3-chloropropane

m-Dichlorobenzene

o-Dichlorobenzene

p-Dichlorobenzene

3,3'-Dichlorobenzidine

1,4-Dichloro-2-butene

1,1-Dichloroethane

1,2-Dichloroethane

1,1-Dichloroethylene

Dichloroisopropyl ether

Dichloromethane @

2,4-Dichlorophenol

2,6-Dichlorophenol

1,2-Dichloropropane

1,3-Dichloropropene

Dieldrin

alpha-Endosulfan

beta-Endosulfan

Endrin

Endrin aldehyde

Heptachlor

Heptachlor epoxide

Hexachlorobenzene

Hexachlorobutadiene

Hexachloroethane

Hexachlorophene

Hexachloropropene

Isodrin

Kepone

Methoxychlor

4,4'-Methylenebis(2-chloroaniline)

Methylene bromide

Pentachlorobenzene

Pentachloroethane

Pentachloronitrobenzene (PCNB)

Pentachlorophenol

Polychlorinated biphenyls (PCBs)

Pronamide

Silvex (2,4,5-TP)

2,4,5-T

TDE

1,2,4,5-Tetrachlorobenzene

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD)

Tetrachloroethane

Tetrachloroethylene

2,3,4,6-Tetrachlorophenol

Toxaphene

1,2,4-Trichlorobenzene

1,1,1-Trichloroethane

1,1,2-Trichloroethane

Trichloroethylene

2,4,5-Trichlorophenol

2,4,6-Trichlorophenol

Tris(2,3-dibromopropyl) phosphate

    (g) Tank car loading and unloading. When placed for loading or 

unloading and before unsecuring any closure, a tank car must be 

protected against movement or coupling as follows:

    (1) The unloader must secure access to the track to prevent entry by 

other rail equipment, including motorized service vehicles. Derails, 

lined and blocked switches, portable bumper blocks, or other equipment 

that provides an equivalent level of security may be used to satisfy 

this requirement.

    (2) Caution signs must be placed between the rails to give necessary 

warning to persons approaching the car(s) from the open end of a siding 

and must be left up until after all closures are secured and the cars 

are in proper condition for transportation. The signs must



[[Page 454]]



be of a durable material, blue in color, rectangular in shape, at least 

30.48 cm (12 inches) high by 38.10 cm (15 inches) wide, and bear the 

word ``STOP.'' The word ``STOP'' must appear in white letters at least 

10.16 cm (4 inches) high. Additional words, such as ``Tank Car 

Connected'' or ``Crew at Work,'' may also appear in white letters under 

the word ``STOP.''

    (3) At least one wheel on the tank car must be blocked against 

movement in both directions, and the hand brakes must be set. If 

multiple tank cars are coupled together, sufficient hand brakes must be 

set and wheels blocked to prevent movement in both directions.



[Amdt. 173-245, 60 FR 49072, Sept. 21, 1995, as amended by Amdt. 173-

245, 61 FR 33254, June 26, 1996; Amdt. 173-256, 61 FR 51338, Oct. 1, 

1996; 65 FR 58629, Sept. 29, 2000; 66 FR 33427, June 21, 2001; 66 FR 

45379, 45381, Aug. 28, 2001; 68 FR 48569, Aug. 14, 2003; 68 FR 75743, 

Dec. 31, 2003; 68 FR 61941, Oct. 30, 2003; 70 FR 34075, June 13, 2005]