Tanks and safety valves in chlorine service must be retested every 2 years at any time during the calendar month the retest falls due. See § 73.314(a) Note 18.

b Special requirements for carbon dioxide-valves must be retested at pressure re-
quired for new construction.

Safety valves indicated with are set at specified pressure plus or minus 3 psi.
All other valves must be open at a pressure not exceeding that specified.

d A commodity for which a tank is approved may be used for filling tank and dome when retesting tanks in service not over 10 years. Safety valve retest period is same as tank retest period.

Tanks must be retested before rubber lining is renewed or before being returned to service after any repairs requiring welding, riveting or calking of rivets. See § 73.31 (a) note 11.

b Nickel clad tanks used in bromine service and lead-lined tanks need not be retested
as prescribed in the table. Safety valves must be retested as prescribed herein.
iGlass or rubber-lined tanks are not subject to periodic retests. Safety valves
must be retested as prescribed herein.

i Safety valves of tanks in bromine service must be retested every 2 years.

Tank must be condemned when it leaks or permanent expansion exceeds 10 percent of the total expansion.

b Reports giving data showing results of these retests must be rendered by the party
making the test to the owner of the tank, and each tank passing the test must be
marked with the date (month and year) plainly and permanently stamped into the
metal of one head or chime. For example, 1-54 for January 1954. Dates of previous
tests must not be obliterated. (On ICC-107A * tanks, date should be stamped
into metal of marked end.)

Safety vents of the frangible disc and fusible plug types must be inspected after
each loaded trip of tank as follows: Remove at least 1 vent for visual inspection and
if it shows signs of deterioration, all the vents must be removed and inspected and
those which do not meet the requirements must be renewed. See Note f for ICC-
107 A**** tanks.

d Each tank must be tested to a pressure at least equal to the marked test pressure of the tank.

e Safety valve must open at a pressure not exceeding the marked test pressure of the tank and must be vapor tight at 80 percent of the marked test pressure of the tank.

ICC-107A**** tanks used for transportation of flammable gasses must have
safety devices of valve type retested once in every 2 years as prescribed. When
safety devices of frangible disc type are used, 1 from each car must be tested as pre-
scribed.

Tank must be condemned when it leaks or shows evidence of distress during
hydrostatic test.

h ICC-107A**** tanks used exclusively in helium gas service shall be exempt from the quinquennial hydrostatic retest requirement until December 31, 1971. This exemption shall be applicable to tank cars presently operated in helium service by the United States Bureau of Mines and to additional cars that are placed in helium service by the Bureau of Mines,

a Tanks and safety valves in chlorine service must be retested every 2 years at any time during the calendar month the retest falls due. See § 73.314(a) Note 18.

b Safety valves indicated with are set at specified pressure plus or minus 3 psi.
All other valves must be open at a pressure not exceeding that specified.

Tanks must be retested before rubber lining is renewed or before being returned to
service after any repairs requiring welding, riveting or calking of rivets.

d Auxiliary safety devices to be retested every 5 years.

(10) All I. C. C. tanks built to one specification and authorized to be stenciled to another specification must be retested in accordance with the higher specification and the test pressure stenciled accordingly on the tank or jacket.

(h) Tank cars and appurtenances may be used for the transportation of any commodity for which they are authorized. Tank cars proposed for a commodity service other than authorized, must be approved for such service by the Association of American Railroads Committee on Tank Cars. Transfer of a tank car from one authorized service to another may be made only by the owner or owner's authorization. Classes ICC-105A type, ICC-109A type, ICC-111A100W-4 (§ 78.306 of this chapter), or ICC112A type tank cars may be used for any commodity for which they are approved by the Committee on Tank Cars when stenciled accordingly. When a tank car is stenciled to indicate that it is authorized for one commodity only, it must not be used for any other service.

NOTE 1: For qualification of cylinders and tank cars for compressed gases see §§ 73.34, 73.301 (g), and 73.314.

(i) A tank car that leaks, or that has any defect which would make leakage during transit probable, or that has not been properly tested and marked, must not be used for the transportation of dangerous articles.

(j) When tanks are loaded and prior to shipping, the shipper must determine to the extent practicable, that the tank, safety appurtenances and fittings are in proper condition for the safe transportation of the lading. Tanks with bottom discharge outlets must have their outlet caps off, or outlet cap plugs open, during the entire time tanks are being loaded. After loading, tanks with bottom outlet valves which permit more than a dropping of the liquid with the outlet caps off, or the outlet cap plugs open, must not be offered for transportation until proper repairs have been made.

(k) Tank cars equipped with interior heater coils, except when coils are rendered inoperative by blocking off the inlet and outlet, must be loaded with heater coil inlet and outlet caps off during entire time tanks are being loaded and show no leakage with caps off.

(1) All closures of openings in tank cars and of their protective housings

must be properly secured in place by the use of a bar, wrench, or other suitable tool. A wrench having a handle at least 36 inches long must be used to apply the outlet valve cap. Manhole covers and outlet valve caps must be made tight against leakage of vapor and liquid, by use of gaskets of suitable materials, before cars are tendered to carrier for transportation. Luting materials must not be used in outlet cap or on threads of bottom outlet.

[15 F.R. 8278, Dec. 2, 1950, as amended by Order 2, 16 F.R. 9372, Sept. 15, 1951; 16 F.R. 9665, Sept. 21, 1951; Order 24, 21 F.R. 4562, June 26, 1956; Order 31, 22 F.R. 4788, July 9, 1957; Order 32, 22 F.R. 7835, Oct. 3, 1957; Order 33, 22 F.R. 11030, Dec. 31, 1957; Order 36, 23 F.R. 7646, Oct. 3, 1958; Order 38, 24 F.R. 3595, May 5, 1959; Order 44, 25 F.R. 10389, Oct. 29, 1960; Order 48, 26 F.R. 4994, June 6, 1961; Order 51, 26 F.R. 9399, Oct. 6, 1961; Order 53, 26 F.R. 12702, Dec. 29, 1961] § 73.32 Qualification, maintenance, and use of portable tanks.

(a) Except as otherwise provided in this section, every portable tank container used for the transportation of dangerous articles shall fulfill the requirements of the specification and regulations for the transportation of the particular commodity. A manufacturer's data report of the portable tank container shall be procured and retained in the files of the owner during the time that such portable tank container is used for such service.

(1) When a portable tank container is used as a cargo tank container, it shall comply with all the requirements prescribed for cargo tank containers. (See § 73.33.)

(2) Portable tank containers for transportation as cargo on vessels in commerce subject to the jurisdiction of the United States Coast Guard shall not exceed a loaded weight of 20,000 pounds. Nothing contained in this section shall be so construed as to pertain to transportation on car floats and car ferries, nor shall such limitation in weight apply to trailerships or containerships if approved under Coast Guard Regulations.

(b) Any portable tank container constructed prior to May 15, 1950, complying with the requirements of either the A. S. M. E. Code for Unfired Pressure Vessels, 1946 Edition, or the A. P. I.-A. S. M. E. Code for Unfired Pressure Vessels, 1943 Edition, may be used for the transportation of liquefied compressed gas, provided it fulfills all the requirements of

this part and specifications for the particular gas or gases to be transported therein and shall be marked “ICC Specification 51X" on the plate required by the specification, except as modified by any or all of the following:

(1) Tanks designed and constructed in accordance with Pars. U-68, U-69, or U-201 of the A. S. M. E. Code may be used. Tanks designed and constructed in accordance with Pars. U-68 or U-69 may be re-rated at a working pressure 25 percent in excess of the design pressure for which the tank was originally constructed. If advantage is taken of the increased rating, the re-rated pressure shall be marked on the plate as follows:

psig.

Re-rated working pressure NOTE 1: For purposes of setting safety relief valves, pressure control valves and establishing retest pressure, and for purposes of establishing maximum and minimum design pressures, the re-rated working pressure shall be considered as the equivalent of the design pressure as defined in the specification.

(2) Loading and unloading accessories, valves, piping, fittings, safety and gauging devices, do not have to comply with the requirements for the particular location on the tank.

(3) Tanks having capacities of between 750 pounds and 1,000 pounds of water shall be considered as portable tank containers for the purposes of this part. In lieu of using safety relief valves on such containers they may be equipped with fusible plugs only when the container is filled by weight. Size, num.ber, and location, as well as character and physical properties of fusible plugs shall be approved by the Bureau of Explosives. These containers shall be marked "ICC Specification 51S".

(4) Specification_requirements as to stress-relieving and radiographing are waived.

(c) Any portable tank container of ICC Specification 50' fulfilling the requirements of that specification may be continued in service for transportation of a liquefied petroleum gas if it is retested every five years in accordance with the requirements of paragraph (e) (3), (4), and (5) of this section: Provided, That it is in and can be maintained in safe operating condition for the transportation of that gas. In this case

1 Use of existing portable tanks authorized, but new construction not authorized.

the container may retain its original markings.

(d) Fusion welded portable tanks manufactured prior to July 19, 1948 in complete compliance with specifications included in ICC Authority No. 3666 dated December 28, 1939 (235 I. C. C. 595),' are authorized for the transportation of commercial butane: Provided, That they are in and can be maintained in safe operating condition for the transportation of that gas and are retested every five years in accordance with the requirements of paragraph (e) (3), (4), and (5) of this section. Certificate of manufacture for each tank and record of each required five year retest is filed with the Bureau of Explosives, and in addition to the markings prescribed by the aforementioned authority each tank is permanently marked "ICC-50X." (See Appendix A to Subpart C of Part 78 of this chapter.)

(e) Portable tank containers used for the transportation of dangerous articles shall be retested in accordance with the following and shall not be kept in or returned to transportation service unless they shall have successfully withstood the following prescribed tests, as appropriate in each instance:

(1) Every portable tank container manufactured in accordance with ICC Specification 60 (§ 78.255 of this chapter) shall be tested at the end of the first 4 year period after the original test and each 2 years thereafter up to 12 years of service and annually thereafter. Except that retests are not required on such tanks equipped with rubber lining but retests must be made before such tanks are relined. Retest of Specification 60 tanks (see § 78.255 of this chapter) to be as required in § 78.255-12 of Specification 60 (§ 78.255 of this chapter) for new tank.

(2) Every portable tank container which is constructed in accordance with ICC Specification 51 (§ 78.245 of this chapter), or qualified for transporting compressed gases as prescribed in these regulations shall be tested at least once in every five years in accordance with paragraph (e) (3), (4), and (5) of this section. A written record indicating the dates and results of all required pressure tests shall be retained by the owner or his authorized agent until the next retest has been accomplished and recorded.

(3) The tank less any fittings shall be subject to a hydrostatic pressure of one and one-half times the design pres