49 CFR 173.316 - Cryogenic liquids in cylinders.

§ 173.316 Cryogenic liquids in cylinders.

(a)General requirements.

(1) A cylinder may not be loaded with a cryogenic liquid colder than the design service temperature of the packaging.

(2) A cylinder may not be loaded with any material which may combine chemically with any residue in the packaging to produce an unsafe condition.

(3) The jacket covering the insulation on a cylinder used to transport any flammable cryogenic liquid must be made of steel.

(4) A valve or fitting made of aluminum with internal rubbing or abrading aluminum parts that may come in contact with oxygen in the cryogenic liquid form may not be installed on any cylinder used to transport oxygen, cryogenic liquid unless the parts are anodized in accordance with ASTM Standard B 580 (IBR, see § 171.7 of this subchapter).

(5) An aluminum valve, pipe or fitting may not be installed on any cylinder used to transport any flammable cryogenic liquid.

(6) Each cylinder must be provided with one or more pressure relief devices, which must be installed and maintained in compliance with the requirements of this subchapter.

(7) Each pressure relief device must be installed and located so that the cooling effect of the contents during venting will not prevent effective operation of the device.

(8) All pressure relief device inlets must under maximum filling conditions be situated in the vapor space of the closed cryogenic receptacle and the devices must be arranged to ensure that the escaping vapor is discharged unobstructed.

(9) The maximum weight of the contents in a cylinder with a design service temperature colder than −320 °F. may not exceed the design weight marked on the cylinder (see § 178.35 of this subchapter).

(b)Pressure control systems. Each cylinder containing a cryogenic liquid must have a pressure control system that conforms to § 173.301(f) and is designed and installed so that it will prevent the cylinder from becoming liquid full.

(c)Specification cylinder requirements and filling limits. Specification DOT-4L cylinders ( § 178.57 of this subchapter) are authorized for the transportation of cryogenic liquids when carried in the vertical position as follows:

(1) For purposes of this section, “filling density,” except for hydrogen, is defined as the percent ratio of the weight of lading in the packaging to the weight of water that the packaging will hold at 60 °F. (1 lb. of water = 27.737 cubic inches at 60 °F.).

(2) The cryogenic liquids of argon, nitrogen, oxygen, helium and neon must be loaded and shipped in accordance with the following table:

Pressure control valve setting (maximum start-to-discharge pressure psig) Maximum permitted filling density (percent by weight)
Air Argon Nitrogen Oxygen Helium Neon
45 82.5 133 76 108 12.5 109
75 80.3 130 74 105 12.5 104
105 78.4 127 72 103 12.5 100
170 76.2 122 70 100 12.5 92
230 75.1 119 69 98 12.5 85
295 73.3 115 68 96 12.5 77
360 70.7 113 65 93 12.5
450 65.9 111 61 91 12.5
540 62.9 107 58 88 12.5
625 60.1 104 55 86 12.5
Design service temperature (°F.) −320 −320 −320 −320 −452 −411

(3) Hydrogen (minimum 95 percent parahydrogen) must be loaded and shipped as follows:

Column 1 Column 2
Design service temperature Minus 423 °F. or colder.
Maximum permitted filling density, based on cylinder capacity at minus 423 °F (see Note 1) 6.7 percent.
The pressure control valve must be designed and set to limit the pressure in the cylinder to not more than 17 psig.
Note 1:

The filling density for hydrogen, cryogenic liquid is defined as the percent ratio of the weight of lading in a packaging to the weight of water that the packaging will hold at minus 423 °F. The volume of the packaging at minus 423 °F is determined in cubic inches. The volume is converted to pounds of water (1 lb. of water = 27.737 cubic inches).

(i) Each cylinder must be constructed, insulated and maintained so that during transportation the total rate of venting shall not exceed 30 SCF of hydrogen per hour.

(ii) In addition to the marking requirements in § 178.35 of this subchapter, the total rate of venting in SCF per hour (SCFH) shall be marked on the top head or valve protection band in letters at least one-half inch high as follows: “VENT RATE**SCFH” (with the asterisks replaced by the number representing the total rate of venting, in SCF per hour).

(iii) Carriage by highway is subject to the conditions specified in § 177.840(a) of this subchapter.

(d)Mixtures of cryogenic liquid. Where charging requirements are not specifically prescribed in paragraph (c) of this section, the cryogenic liquid must be shipped in packagings and under conditions approved by the Associate Administrator.

[Amdt. 173-166, 48 FR 27695, June 16, 1983, as amended by Amdt. 173-166, 49 FR 24314, June 12, 1984; Amdt. 173-180, 49 FR 42735, Oct. 24, 1984; Amdt. 173-201, 52 FR 13041, Apr. 20, 1987: Amdt. 173-250, 61 FR 25942, May 23, 1996; Amdt. 173-261, 62 FR 24741, May 6, 1997; 66 FR 45379, Aug. 28, 2001; 67 FR 16013, Sept. 27, 2002; 68 FR 75742, Dec. 31, 2003; 69 FR 54046, Sept. 7, 2004; 78 FR 1092, Jan. 7, 2013]

This is a list of United States Code sections, Statutes at Large, Public Laws, and Presidential Documents, which provide rulemaking authority for this CFR Part.

This list is taken from the Parallel Table of Authorities and Rules provided by GPO [Government Printing Office].

It is not guaranteed to be accurate or up-to-date, though we do refresh the database weekly. More limitations on accuracy are described at the GPO site.

United States Code

Title 49 published on 09-May-2017 04:41

The following are ALL rules, proposed rules, and notices (chronologically) published in the Federal Register relating to 49 CFR Part 173 after this date.

  • 2017-03-30; vol. 82 # 60 - Thursday, March 30, 2017
    1. 82 FR 15796 - Hazardous Materials: Harmonization With International Standards (RRR)
      GPO FDSys XML | Text
      DEPARTMENT OF TRANSPORTATION, Pipeline and Hazardous Materials Safety Administration
      Final rule.
      Effective date: This rule is effective March 30, 2017, except for instruction 22, which is effective January 2, 2019. Voluntary compliance date: January 1, 2017. Delayed compliance date: Unless otherwise specified, compliance with the amendments adopted in this final rule is required beginning January 1, 2018. Incorporation by reference date: The incorporation by reference of certain publications listed in this rule is approved by the Director of the Federal Register as of March 30, 2017.
      49 CFR Parts 107, 171, 172, 173, 175, 176, 178, and 180