(a) General requirements. A cylinder filled with a liquefied compressed gas (except gas in solution) must be offered for transportation in accordance with the requirements of this section and the general requirements in Sec. 173.301. In addition, a DOT specification cylinder must meet the requirement in Secs. 173.301a, 173.304a, and 173.305, as applicable. UN pressure receptacles must be shipped in accordance with the requirements in 173.301b and 173.304b, as applicable.
(1) A DOT 3AL cylinder may not be used for any material with a primary or subsidiary hazard of Class 8.
(2) Shipments of Division 2.1 materials in aluminum cylinders are authorized only when transported by motor vehicle, rail car, or cargo-only aircraft.
(b) Filling limits. Except for carbon dioxide; 1,1-Difluoroethylene (R-1132A); nitrous oxide; and vinyl fluoride, inhibited, the liquid portion of a liquefied gas may not completely fill the packaging at any temperature up to and including 55 C (131 F). The liquid portion of vinyl fluoride, inhibited, may completely fill the cylinder at 55 C (131 F) provided the pressure at the critical temperature does not exceed 1.25 times the service pressure of the cylinder.
(c) Mixture of compressed gas and other material. A mixture of compressed gas must be shipped in accordance with Sec. 173.305.
(d) Refrigerant and dispersant gases. Nontoxic and nonflammable refrigerant or dispersant gases must be offered for transportation in cylinders prescribed in Sec. 173.304a, or in DOT 2P and 2Q containers (Secs. 178.33, 178.33a of this subchapter). DOT 2P and 2Q containers must be packaged in a strong wooden or fiberboard box of such design as to protect valves from damage or accidental functioning under conditions incident to transportation. Pressure in the inside metal containers may not exceed 87 psia at 21 C (70 F). Each completed metal container filled for shipment must be heated until its contents reach a minimum temperature of 55 C (131 F) without evidence of leakage, distortion, or other defect. Each outside package must be plainly marked ``INSIDE CONTAINERS COMPLY WITH PRESCRIBED SPECIFICATIONS''.
(e) Engine starting fluid. Engine starting fluid containing a flammable compressed gas or gases must be shipped in a cylinder as prescribed in Sec. 173.304a or as follows:
(1) Inside non-refillable metal containers having a capacity not greater than 500 mL (32 in \3\). The containers must be packaged in strong, tight outer packagings. The pressure in the container may not exceed 145 psia at 54 C (130 F). If the pressure exceeds 145 psia at 54 C (130 F), a DOT 2P container must be used. In either case, the metal container must be capable of withstanding, without bursting, a pressure of 1.5 times the pressure of the contents at 54 C (130 F). The liquid content of the material and gas may not completely fill the container at 54 C (130 F). Each container filled for shipment must have been heated until its contents reach a minimum temperature of 54 C (130 F), without evidence of leakage, distortion, or other defect. Each outside shipping container must be plainly marked, ``INSIDE CONTAINERS COMPLY WITH PRESCRIBED SPECIFICATIONS''.
(2) [Reserved]
(f) Oxidizing gases by aircraft. A cylinder containing carbon dioxide and oxygen mixture, compressed; liquefied gas, oxidizing, n.o.s.; or nitrous oxide is authorized for transportation by aircraft only when it meets the following requirements:
(1) Only DOT specification 3A, 3AA, 3AL, 3E, 3HT, and 39 cylinders, and UN pressure receptacles ISO 9809-1, ISO 9809-2, ISO 9809-3 and ISO 7866 cylinders are authorized.
(2) Cylinders must be equipped with a pressure relief device in accordance with Sec. 173.301(f) and, for DOT 39 cylinders offered for transportation after October 1, 2008, for the other DOT specification cylinders with the first requalification due after October 1, 2008, or for the UN pressure receptacles prior to initial use:
(i) The rated burst pressure of a rupture disc for DOT 3A, 3AA, 3AL, 3E and 39 cylinders, and UN pressure receptacles ISO 9809-1, ISO 9809-2, ISO 9809-3 and ISO 7866 cylinders must be 100% of the cylinder minimum test pressure with a tolerance of plus zero to minus 10%; and
(ii) The rated burst pressure of a rupture disc for a DOT 3HT cylinder must be 90% of the cylinder minimum test pressure with a tolerance of plus zero to minus 10%.
(3) The cylinder must be placed in a rigid outer packaging that--
(i) Conforms to the requirements of either part 178, subparts L and M, of this subchapter at the Packing Group I or II performance level, or the performance criteria in Air Transport Association (ATA) Specification No. 300 for a Category I Shipping Container;
(ii) Is capable of passing, as demonstrated by design testing, the Flame Penetration Resistance Test in appendix E to part 178 of this subchapter; and
(iii) Prior to each shipment, passes a visual inspection that verifies that all features of the packaging are in good condition, including all latches, hinges, seams, and other features, and the packaging is free from perforations, cracks, dents, or other abrasions that may negatively affect the flame penetration resistance and thermal resistance characteristics of the container.
(4) The cylinder and the outer packaging must be capable of passing, as demonstrated by design testing, the Thermal Resistance Test specified in appendix D to part 178 of this subchapter.
(5) The cylinder and the outer packaging must both be marked and labeled in accordance with part 172, subparts D and E of this subchapter. The additional marking ``DOT31FP,'' is allowed to indicate that the cylinder and the outer packaging are capable of passing, as demonstrated by design testing, the Thermal Resistance Test specified in appendix D to part 178 of this subchapter.
(6) A cylinder of compressed oxygen that has been furnished by an aircraft operator to a passenger in accordance with 14 CFR 121.574, 125.219, or 135.91 is excepted from the outer packaging requirements of paragraph (f)(3) of this section. [67 FR 51647, Aug. 8, 2002, as amended at 68 FR 24661, May 8, 2003; 71 FR 33883, June 12, 2006; 72 FR 55098, Sept. 28, 2007; 74 FR 53188, Oct. 16, 2009; 76 FR 56317, Sept. 13, 2011; 78 FR 60754, Oct. 2, 2013] Sec. 173.304a Additional requirements for shipment of liquefiedcompressed gases in specification cylinders.
(a) Detailed filling requirements. Liquefied gases (except gas in solution) must be offered for transportation, subject to the requirements in this section and Secs. 173.301 and 173.304, in specification cylinders, as follows:
(1) DOT 3, 3A, 3AA, 3AL, 3B, 3BN, 3E, 4B, 4BA, 4B240ET, 4BW, 4E, 39, except that no DOT 4E or 39 packaging may be filled and shipped with a mixture containing a pyrophoric liquid, carbon bisulfide (disulfide), ethyl chloride, ethylene oxide, nickel carbonyl, spirits of nitroglycerin, or toxic material (Division 6.1 or 2.3), unless specifically authorized in this part.
(2) For the gases named, the following requirements apply (for cryogenic liquids, see Sec. 173.316): ------------------------------------------------------------------------
Packaging marked as
shown in this column
or of the same type
with higher service
Maximum permitted pressure must be
Kind of gas filling density used, except as
(percent) (see provided in
Note 1) 173.301(l),
173.301a(e), and
180.205(a) (see notes
following table)------------------------------------------------------------------------Anhydrous ammonia............. 54............... DOT-3A480; DOT-
3AA480; DOT-3A480X;
DOT-4AA480; DOT-3;
DOT-3E1800; DOT-
3AL480.Bromotrifluoromethane (R-13B1 124.............. DOT-3A400; DOT-
or H-1301). 3AA400; DOT-3B400;
DOT-4AA480; DOT-
4B400; DOT-4BA400;
DOT-4BW400; DOT-
3E1800; DOT-39; DOT-
3AL400.Carbon dioxide (see Notes 4, 68............... DOT-3A1800; DOT-
7, and 8). 3AX1800; DOT-
3AA1800; DOT-
3AAX1800; DOT-3; DOT-
3E1800; DOT-3T1800;
DOT-3HT2000; DOT-39;
DOT-3AL1800.Carbon dioxide, refrigerated ................. DOT-4L.
liquid (see paragraph (e) of
this section).Chlorine (see Note 2)......... 125.............. DOT-3A480; DOT-
3AA480; DOT-3; DOT-
3BN480; DOT-3E1800.Chlorodifluroethane or 1- 100.............. DOT-3A150; DOT-
Chloro-1, 1-difluoroethane (R- 3AA150; DOT-3B150;
142b). DOT-4B150; DOT-
4BA225; DOT-4BW225;
DOT-3E1800; DOT-39;
DOT-3AL150.Chlorodifluoromethane (R-22) 105.............. DOT-3A240; DOT-
(see Note 8). 3AA240; DOT-3B240;
DOT-4B240; DOT-
4BA240; DOT-4BW240;
DOT-4B240ET; DOT-
4E240; DOT-39; DOT-
3E1800; DOT-3AL240.Chloropentafluorethane (R-115) 110.............. DOT-3A225; DOT-
3AA225; DOT-3B225;
DOT-4BA225; DOT-
4B225; DOT-4BW225;
DOT-3E1800; DOT-39;
DOT-3AL225.Chlorotrifluoromethane (R-13) 100.............. DOT-3A1800; DOT-
(see Note 8). 3AA1800; DOT-3; DOT-
3E1800; DOT-39; DOT-
3AL1800.Cyclopropane (see Note 8)..... 55............... DOT-3A225; DOT-
3A480X; DOT-3AA225;
DOT-3B225; DOT-
4AA480; DOT4B225;
DOT-4BA225; DOT-
4BW225; DOT-4B240ET;
DOT-3; DOT-3E1800;
DOT-39; DOT-3AL225.Dichlorodifluoromethane (R-12) 119.............. DOT-3A225; DOT-
(see Note 8). 3AA225; DOT-3B225;
DOT-4B225; DOT-
4BA225; DOT-4BW225;
DOT-4B240ET; DOT-
4E225; DOT-39; DOT-
3E1800; DOT-3AL225.Dichlorodifluoromethane and Not liquid full DOT-3A240; DOT-
difluoroethane mixture at 131 F. 3AA240; DOT-3B240;
(constant boiling mixture) (R- DOT-3E1800; DOT-
500) (see Note 8). 4B240; DOT-4BA240;
DOT-4BW240; DOT-
4E240; DOT-39.1,1-Difluoroethane (R-152a) 79............... DOT-3A150; DOT-
(see note 8). 3AA150; DOT-3B150;
DOT-4B150; DOT-
4BA225; DOT-4BW225;
DOT-3E1800; DOT-
3AL150.1,1-Difluoroethylene (R-1132A) 73............... DOT-3A2200; DOT-
3AA2200; DOT-
3AX2200; DOT-
3AAX2200; DOT-
3T2200; DOT-39.
Dimethylamine, anhydrous...... 59............... DOT-3A150; DOT-
3AA150; DOT-3B150;
DOT-4B150; DOT-
4BA225; DOT-4BW225;
ICC-3E1800.Ethane (see Note 8)........... 35.8............. DOT-3A1800; DOT-
3AX1800; DOT-
3AA1800; DOT-
3AAX1800; DOT-3; DOT-
3E1800; DOT-3T1800;
DOT-39; DOT-3AL1800.Ethane (see Note 8)........... 36.8............. DOT-3A2000; DOT-
3AX2000; DOT-
3AA2000; DOT-
3AAX2000; DOT-
3T2000; DOT-39; DOT-
3AL2000.Ethylene (see Note 8)......... 31.0............. DOT-3A1800; DOT-
3AX1800; DOT-
3AA1800; DOT-
3AAX1800; DOT-3; DOT-
3E1800; DOT-3T1800;
DOT-39; DOT-3AL1800.Ethylene (see Note 8)......... 32.5............. DOT-3A2000; DOT-
3AX2000; DOT-
3AA2000; DOT-
3AAX2000; DOT-
3T2000; DOT-39; DOT-
3AL2000.Ethylene (see Note 8)......... 35.5............. DOT-3A2400; DOT-
3AX2400; DOT-
3AA2400; DOT-
3AAX2400; DOT-
3T2400; DOT-39; DOT-
3AL2400.Hydrogen chloride, anhydrous.. 65............... DOT-3A1800; DOT-
3AA1800; DOT-
3AX1800; DOT-
3AAX1800; DOT-3; DOT-
3T1800; DOT-3E1800.Hydrogen sulfide (see Notes 10 62.5............. DOT-3A; DOT-3AA; DOT-
and 14). 3B; DOT-4A; DOT-4B;
DOT-4BA; DOT-4BW;
DOT-3E1800; DOT-3AL.Insecticide, gases liquefied Not liquid full DOT-3A300; DOT-
(see Notes 8 and 12). at 131 F. 3AA300; DOT-3B300;
DOT-4B300; DOT-
4BA300; DOT-4BW300;
DOT-3E1800.Liquefied nonflammable gases, Not liquid full Specification
other than classified at 131 F. packaging authorized
flammable, corrosive, toxic & in paragraph (a)(1)
mixtures or solution thereof of this section and
filled w/nitrogen, carbon DOT-3HT; DOT 4D; DOT-
dioxide, or air (see Notes 7 4DA; DOT-4DS.
and 8)..Methyl acetylene-propadiene, Not liquid at 131 DOT-4B240 without
mixtures, stabilized; (see F. brazed seams; DOT-
Note 5).. 4BA240 without
brazed seams; DOT-
3A240; DOT-3AA240;
DOT-3B240; DOT-
3E1800; DOT-4BW240;
DOT-4E240; DOT-
4B240ET; DOT-3AL240.Methyl chloride............... 84............... DOT-3A225; DOT-
3AA225; DOT-3B225;
DOT-4B225; DOT-
4BA225; DOT-4BW225;
DOT-3; DOT-3E1800;
DOT-4B240ET.
Cylinders complying
with DOT-3A150; DOT-
3B150; and DOT-4B150
manufactured prior
to Dec. 7, 1936 are
also authorized.Methyl mercaptan.............. 80............... DOT-3A240; DOT-
3AA240; DOT-3B240;
OT-4B240; DOT-
4B240ET; DOT-3E1800;
DOT-4BA240; DOT-
4BW240.Nitrosyl chloride............. 110.............. DOT-3BN400 only.Nitrous oxide (see Notes 7, 8, 68............... DOT-3A1800; DOT-
and 11). 3AX1800; DOT-
3AA1800; DOT-
3AAX1800; DOT-3; DOT-
3E1800; DOT-3T1800;
DOT-3HT2000; DOT-39;
DOT- 3AL1800.Nitrous oxide, refrigerated ................. DOT-4L.
liquid (see paragraph (e) of
this section.).Refrigerant gas, n.o.s. or Not liquid full DOT-3A240; DOT-
Dispersant gas, n.o.s. (see at 130 F. 3AA240; DOT-3B240;
Notes 8 and 13). DOT-3E1800; DOT-
4B240; DOT-4BA240;
DOT-4BW240; DOT-
4E240; DOT-39; DOT-
3AL240.Sulfur dioxide (see note 8)... 125.............. DOT-3A225; DOT-
3AA225; DOT-3B225;
DOT-4B225; DOT-
4BA225; DOT-4BW225;
DOT-4B240ET; DOT-3;
DOT-39; DOT-3E1800;
DOT-3AL225.Sulfur hexafluoride........... 120.............. DOT-3A1000; DOT-
3AA1000; DOT-
AAX2400; DOT-3; DOT-
3AL1000; DOT-3E1800;
DOT-3T1800.Sulfuryl fluoride............. 106.............. DOT-3A480; DOT-
3AA480; DOT-3E1800;
DOT-4B480; DOT-
4BA480; DOT-4BW480.Tetrafluoroethylene, 90............... DOT-3A1200; DOT-
stabilized. 3AA1200; DOT-3E1800.Trifluorochloroethylene, 115.............. DOT-3A300; DOT-
stabilized. 3AA300; DOT-3B300;
DOT-4B300; DOT-
4BA300; DOT-4BW300;
DOT-3E1800.
Trimethylamine, anhydrous..... 57............... DOT-3A150; DOT-
3AA150; DOT-3B150;
DOT-4B150; DOT-
4BA225; DOT-4BW225;
DOT-3E1800.Vinyl chloride (see Note 5)... 84............... DOT-4B150 without
brazed seams; DOT-
4BA225 without
brazed seams; DOT-
4BW225; DOT-3A150;
DOT-3AA150; DOT-
3E1800; DOT-3AL150.Vinyl fluoride, stabilized.... 62............... DOT-3A1800; DOT-
3AA1800; DOT-3E1800;
DOT-3AL1800.Vinyl methyl ether, 68............... DOT-4B150, without
stabilized(see Note 5). brazed seams; DOT-
4BA225 without
brazed seams; DOT-
4BW225; DOT-3A150;
DOT-3AA150; DOT-
3B1800; DOT-3E1800.------------------------------------------------------------------------Note 1: ``Filling density'' means the percent ratio of the weight of gas
in a packaging to the weight of water that the container will hold at
16 C (60 F). (1 lb of water = 27.737 in \3\ at 60 F.).Note 2: Cylinders purchased after Oct. 1, 1944, for the transportation
of chlorine must contain no aperture other than that provided in the
neck of the cylinder for attachment of a valve equipped with an
approved pressure relief device. Cylinders purchased after Nov. 1,
1935, and filled with chlorine may not contain over 68.04 kg (150 lb)
of gas.Note 3: [Reserved]Note 4: Special carbon dioxide mining devices containing a heating
element and filled with not over 2.72 kg (6 lb) of carbon dioxide may
be filled to a density of not over 85 percent, provided the cylinder
is made of steel with a calculated bursting pressure in excess of
39000 psig, fitted with a frangible disc that will operate at not over
57 percent of that pressure, and is able to withstand a drop of 10
feet when striking crosswise on a steel rail while under a pressure of
at least 3000 psig. Such devices must be shipped in strong boxes or
must be wrapped in heavy burlap and bound by 12-gauge wire with the
wire completely covered by friction tape. Wrapping must be applied so
as not to interfere with the functioning of the frangible disc
pressure relief device. Shipments must be described as ``liquefied
carbon dioxide gas (mining device)'' and marked, labeled, and
certified as prescribed for liquefied carbon dioxide.Note 5: All parts of valve and pressure relief devices in contact with
contents of cylinders must be of a metal or other material, suitably
treated if necessary, that will not cause formation of any acetylides.
Note 6: [Reserved]Note 7: Specification 3HT cylinders for aircraft use only, having a
maximum service life of 24 years. Authorized only for nonflammable
gases. Cylinders must be equipped with pressure relief devices of the
frangible disc type that meet the requirements of Sec. 173.301(f).
Each frangible disc must have a rated bursting pressure that does not
exceed 90 percent of the minimum required test pressure of the
cylinder. Discs with fusible metal backing are not permitted.
Cylinders may be offered for transportation only when packaged in
accordance with Sec. 173.301(a)(9).Note 8: See Sec. 173.301(a)(9).Note 9: [Reserved]Note 10: Each valve outlet must be sealed by a threaded cap or a
threaded solid plug.Note 11: Must meet the valve and cleaning requirements in Sec.
173.302(b).Note 12: For an insecticide gas that is nontoxic and nonflammable, see
Sec. 173.305(c).Note 13: For a refrigerant or dispersant gas that is nontoxic and
nonflammable, see Sec. 173.304(d).Note 14: The use of DOT specification cylinder with a marked service
pressure of 480 psi is authorized until December 31, 2003.
(b) [Reserved]
(c) Verification of content in cylinder. Except as noted in paragraph (d)(4) of this section, the amount of liquefied gas filled into a cylinder must be by weight or, when the gas is lower in pressure than required for liquefaction, a pressure-temperature chart for the specific gas may be used to ensure that the service pressure at 55 C (131 F) will not exceed \5/4\ of the service pressure at 21 C (70 F). The weight of liquefied gas filled into the cylinder also must be checked, after disconnecting the cylinder from the filling line, by the use of an accurate scale.
(d) Requirements for liquefied petroleum gas. (1) Filling density limits are as follows: ------------------------------------------------------------------------
Maximum the filling density in
Minimum specific gravity of liquid percent of the water-weight
material at 60 F capacity of the cylinder------------------------------------------------------------------------0.271 to 0.289...................... 260.290 to 0.306...................... 270.307 to 0.322...................... 280.323 to 0.338...................... 290.339 to 0.354...................... 300.355 to 0.371...................... 310.372 to 0.398...................... 320.399 to 0.425...................... 330.426 to 0.440...................... 340.441 to 0.452...................... 350.453 to 0.462...................... 360.463 to 0.472...................... 370.473 to 0.480...................... 380.481 to 0.488...................... 390.489 to 0.495...................... 400.496 to 0.503...................... 410.504 to 0.510...................... 420.511 to 0.519...................... 430.520 to 0.527...................... 440.528 to 0.536...................... 450.537 to 0.544...................... 460.545 to 0.552...................... 470.553 to 0.560...................... 480.561 to 0.568...................... 490.569 to 0.576...................... 50
0.577 to 0.584...................... 510.585 to 0.592...................... 520.593 to 0.600...................... 530.601 to 0.608...................... 540.609 to 0.617...................... 550.618 to 0.626...................... 560.627 to 0.634...................... 57------------------------------------------------------------------------
(2) Subject to Sec. 173.301a(d), any filling density percentage prescribed in this section is authorized to be increased by a factor of 2 for liquefied petroleum gas in DOT 3 cylinders or in DOT 3A cylinders marked for 1800 psig, or higher, service pressure.
(3) Liquefied petroleum gas must be shipped in specification cylinders as follows:
(i) DOT 3, 3A, 3AA, 3B, 3E, 3AL, 4B, 4BA, 4B240ET, 4BW, 4E, or 39 cylinders. Shipments of flammable gases in DOT 3AL cylinders are authorized only when transported by motor vehicle, rail car, or cargo-only aircraft.
(ii) Additional containers may be used within the limits of quantity and pressure as follows: ------------------------------------------------------------------------
Maximum
capacity Maximum filling pressure
Type of container (cubic (psig)
inches)------------------------------------------------------------------------DOT-2P or DOT-2Q (see Note 1).... 31.83 45 psig at 70 F and 105
psig at 130 F (see Note
2).DOT-2P or DOT-2Q (see Note 1).... 31.83 35 psig at 70 F and 100
psig at 130 F.------------------------------------------------------------------------Note 1: Containers must be packed in strong wooden or fiber boxes of
such design as to protect valves from damage or accidental functioning
under conditions normally incident to transportation. Each completed
container filled for shipment must have been heated until its contents
reach a temperature of 54 C (130 F), without evidence of leakage,
distortion, or other defect. Each outside shipping container must be
plainly marked ``INSIDE CONTAINERS COMPLY WITH PRESCRIBED
SPECIFICATIONS'.Note 2: A container must be equipped with a pressure relief device that
will prevent rupture of the container and dangerous projection of a
closing device when exposed to fire.
(4) Verification of content. A cylinder with a water capacity of 90.72 kg (200 lb) or more and for use with a liquefied petroleum gas with a specific gravity of 0.504 or greater at 16 C (60 F) may have the quantity of its contents determined by using a fixed length dip tube gauging device. The length of the dip tube must be such that when a liquefied petroleum gas, with a specific volume of 0.03051 cu. ft./lb. at a temperature of 40 F, is filled into the container, the liquid just reaches the bottom of the tube. The weight of this liquid may not exceed 42 percent of the water capacity of the container, which must be stamped on the cylinder. The length of the dip tube, expressed in inches carried out to one decimal place and prefixed with the letters ``DT'', must be stamped on the container and on the exterior of removable type dip tube. For the purpose of this requirement, the marked length must be expressed as the distance measured along the axis of a straight tube from the top of the boss through which the tube is inserted to the proper level of the liquid in the container. The length of each dip tube must be checked when installed by weighing each container after filling except when installed in groups of substantially identical containers, in which case one of each 25 containers must be weighed. The quantity of liquefied gas in each container must be checked by means of the dip tube after disconnecting from the filling line. The outlet from the dip tube may not be larger than 0.1016 centimeters (0.040 inch; No. 54 drill bit size orifice). A container representative of each day's filling at each filling plant must have its contents checked by weighing after disconnecting from the filling line.
(e) Carbon dioxide, refrigerated liquid or nitrous oxide, refrigerated liquid. (1) The following provisions apply to carbon dioxide, refrigerated liquid, and nitrous oxide, refrigerated liquid:
(1) The following provisions apply to carbon dioxide, refrigerated liquid, and nitrous oxide, refrigerated liquid:
(i) DOT 4L cylinders conforming to the provisions of this paragraph are authorized.
(ii) Each cylinder must be protected with at least one pressure relief device and at least one frangible disc conforming to Sec. 173.301(f) and paragraph (a)(2) of this section. The relieving capacity of the pressure relief device system must be equal to or greater than that calculated by the applicable formula in paragraph 5.8.3 of CGA S-1.1 (IBR, see Sec. 171.7 of this subchapter).
(iii) The temperature and pressure of the gas at the time the shipment is offered for transportation may not exceed -18 C (0 F) and 290 psig for carbon dioxide and -15.6 C ( + 4 F) and 290 psig for nitrous oxide. Maximum time in transit may not exceed 120 hours.
(2) The following pressure relief device settings, design service temperatures and filling densities apply: ----------------------------------------------------------------------------------------------------------------
Maximum permitted filling density (percent by weight)
Pressure relief device setting maximum -----------------------------------------------------------------------
start--to discharge gauge pressure in Carbon dioxide, refrigerated
psig liquid Nitrous oxide, refrigerated liquid----------------------------------------------------------------------------------------------------------------105 psig................................ 108 104170 psig................................ 105 101230 psig................................ 104 99295 psig................................ 102 97360 psig................................ 100 95450 psig................................ 98 83540 psig................................ 92 87625 psig................................ 86 80Design service temperature C (F)........ -196 C (-320 F) -196 C (-320 F)---------------------------------------------------------------------------------------------------------------- [67 FR 51647, Aug. 8, 2002, as amended at 68 FR 24661, May 8, 2003; 68 FR 57632, Oct. 6, 2003; 68 FR 75742, Dec. 31, 2003; 70 FR 34076, June 13, 2005; 72 FR 4456, Jan. 31, 2007; 72 FR 55098, Sept. 28, 2007; 73 FR 4719, Jan. 28, 2008]
Editorial Note: At 70 FR 34076, June 13, 2005, Sec. 173.304a was amended in the table in paragraph (a)(2) by removing the phrase ``DOT-4A480'' from the entry ``Hydrogen sulfide''; however, the amendment could not be incorporated because that phrase does not exist in the entry. Sec. 173.304b Additional requirements for shipment of liquefiedcompressed gases in UN pressure receptacles.
(a) General. Liquefied gases and gas mixtures must be offered for transportation in UN pressure receptacles subject to the requirements in this section and Sec. 173.304. In addition, the general requirements applicable to UN pressure receptacles in Secs. 173.301 and 173.301b must be met.
(b) UN pressure receptacle filling limits. A UN pressure receptacle is authorized for the transportation of liquefied compressed gases and gas mixtures as specified in this section. When a liquefied compressed gas or gas mixture is transported in a UN pressure receptacle, the filling ratio may not exceed the maximum filling ratio prescribed in this section and the applicable ISO standard. Compliance with the filling limits may be determined by referencing the numerical values and data in Table 2 of P200 of the UN Recommendations (IBR, see Sec. 171.7 of this subchapter). Alternatively, the maximum allowable filling limits may be determined as follows:
(1) For high pressure liquefied gases, in no case may the filling ratio of the settled pressure at 65 C (149 F) exceed the test pressure of the UN pressure receptacle.
(2) For low pressure liquefied gases, the filling factor (maximum mass of contents per liter of water capacity) must be less than or equal to 95 percent of the liquid phase at 50 C. In addition, the UN pressure receptacle may not be liquid full at 60 C. The test pressure of the pressure receptacle must be equal to or greater than the vapor pressure of the liquid at 65 C.
(3) For high pressure liquefied gases or gas mixtures, the maximum filling ratio may be determined using the formulas in (3)(b) of P200 of the UN Recommendations.
(4) For low pressure liquefied gases or gas mixtures, the maximum filling ratio may be determined using the formulas in (3)(c) of P200 of the UN Recommendations.
(c) Tetraflouroethylene, stabilized, UN1081 must be packaged in a pressure receptacle with a minimum test pressure of 200 bar and a working pressure not exceeding 5 bar.
(d) Fertilizer ammoniating solution with free ammonia, UN1043 is not authorized in UN tubes or MEGCs. [74 FR 2265, Jan. 14, 2009]