Every portable tank shall be fitted with a corrosion resistant metal plate permanently attached to the
portable tank in a conspicuous place readily accessible for inspection. When for reasons of portable
tank arrangements the plate cannot be permanently attached to the shell, the shell shall be marked with
at least the information required by the pressure vessel code. As a minimum, at least the following
information shall be marked on the plate by stamping or by any other similar method:
(a) Owner information
(i) Owner’s registration number;
(b) Manufacturing information
(i) Country of manufacture;
(ii) Year of manufacture;
(iii) Manufacturer’s name or mark;
(iv) Manufacturer’s serial number;
(c) Approval information
(i) The United Nations packaging symbol 
This symbol shall not be used for any purpose other than certifying that a packaging, a
flexible bulk container, a portable tank or a MEGC complies with the relevant
requirements in Chapter 6.1, 6.2, 6.3, 6.5, 6.6, 6.7 or 6.11;
(ii) Approval country;
(iii) Authorized body for the design approval;
(iv) Design approval number;
(v) Letters ‘AA’, if the design was approved under alternative arrangements (see;
(vi) Pressure vessel code to which the shell is designed;
(d) Pressures
(i) MAWP (in bar gauge or kPa gauge)3;
(ii) Test pressure (in bar gauge or kPa gauge)3;
(iii) Initial pressure test date (month and year);
3 The unit used shall be indicated.
(iv) Identification mark of the initial pressure test witness;
(v) External design pressure6 (in bar gauge or kPa gauge)3;
(e) Temperatures
(i) Design temperature range (in °C)3;
(ii) Design reference temperature (in °C)3;
(f) Materials
(i) Shell material(s) and material standard reference(s);
(ii) Equivalent thickness in reference steel (in mm)3;
(g) Capacity
(i) Tank water capacity at 20 °C (in litres)3;
(h) Periodic inspections and tests
(i) Type of the most recent periodic test (2.5-year, 5-year or exceptional);
(ii) Date of the most recent periodic test (month and year);
(iii) Test pressure (in bar gauge or kPa gauge)3 of the most recent periodic test (if applicable);
(iv) Identification mark of the authorized body who performed or witnessed the most recent
6 See
3 The unit used shall be indicated.

The following information shall be durably marked either on the portable tank itself or on a metal
plate firmly secured to the portable tank:
Name of the operator
Name of non-refrigerated liquefied gas(es) permitted for carriage
Maximum permissible load mass for each non-refrigerated liquefied gas permitted ________kg
Maximum permissible gross mass (MPGM)__________kg
Unladen (tare) mass_________kg
Portable tank instruction in accordance with

If a portable tank is designed and approved for handling in open seas, the words "OFFSHORE
PORTABLE TANK" shall be marked on the identification plate.

Requirements for the design, construction, inspection and testing of portable tanks intended for the carriage of refrigerated liquefied gases


For the purposes of this section:
Alternative arrangement means an approval granted by the competent authority for a portable tank or
MEGC that has been designed, constructed or tested to technical requirements or testing methods
other than those specified in this Chapter;
Portable tank means a thermally insulated multimodal tank having a capacity of more than 450 litres
fitted with service equipment and structural equipment necessary for the carriage of refrigerated
liquefied gases. The portable tank shall be capable of being filled and discharged without the removal
of its structural equipment. It shall possess stabilizing members external to the tank, and shall be
capable of being lifted when full. It shall be designed primarily to be loaded onto a vehicle, wagon or
sea-going or inland navigation vessel and shall be equipped with skids, mountings or accessories to
facilitate mechanical handling. Tank-vehicles, tank-wagons, non-metallic tanks, intermediate bulk
containers (IBCs), gas cylinders and large receptacles are not considered to fall within the definition
for portable tanks;
Tank means a construction which normally consists of either :
(a) A jacket and one or more inner shells where the space between the shell(s) and the jacket is
exhausted of air (vacuum insulation) and may incorporate a thermal insulation system; or
(b) A jacket and an inner shell with an intermediate layer of solid thermally insulating material
(e.g. solid foam);
Shell means the part of the portable tank which retains the refrigerated liquefied gas intended for
carriage, including openings and their closures, but does not include service equipment or external
structural equipment;
Jacket means the outer insulation cover or cladding which may be part of the insulation system;
Service equipment means measuring instruments and filling, discharge, venting, safety, pressurizing,
cooling and thermal insulation devices;
Structural equipment means the reinforcing, fastening, protective and stabilizing members external to
the shell;
Maximum allowable working pressure (MAWP) means the maximum effective gauge pressure
permissible at the top of the shell of a loaded portable tank in its operating position including the
highest effective pressure during filling and discharge;
Test pressure means the maximum gauge pressure at the top of the shell during the pressure test;
Leakproofness test means a test using gas subjecting the shell and its service equipment, to an
effective internal pressure not less than 90% of the MAWP;
Maximum permissible gross mass (MPGM) means the sum of the tare mass of the portable tank and
the heaviest load authorized for carriage;
Holding time means the time that will elapse from the establishment of the initial filling condition
until the pressure has risen due to heat influx to the lowest set pressure of the pressure limiting
Reference steel means a steel with a tensile strength of 370 N/mm2 and an elongation at fracture
of 27%;
Minimum design temperature means the temperature which is used for the design and construction of
the shell not higher than the lowest (coldest) temperature (service temperature) of the contents during
normal conditions of filling, discharge and carriage.

General design and construction requirements

Shells shall be designed and constructed in accordance with the requirements of a pressure vessel code
recognized by the competent authority. Shells and jackets shall be made of metallic materials suitable
for forming. Jackets shall be made of steel. Non-metallic materials may be used for the attachments
and supports between the shell and jacket, provided their material properties at the minimum design
temperature are proven to be sufficient. The materials shall in principle conform to national or
international material standards. For welded shells and jackets only materials whose weldability has
been fully demonstrated shall be used. Welds shall be skilfully made and afford complete safety.
When the manufacturing process or the materials make it necessary, the shell shall be suitably heat
treated to guarantee adequate toughness in the weld and in the heat affected zones. In choosing the
material, the minimum design temperature shall be taken into account with respect to risk of brittle
fracture, to hydrogen embrittlement, to stress corrosion cracking and to resistance to impact. When
fine grain steel is used, the guaranteed value of the yield strength shall be not more than 460 N/mm2
and the guaranteed value of the upper limit of the tensile strength shall be not more than 725 N/mm2
in accordance with the material specifications. Portable tank materials shall be suitable for the external
environment in which they may be carried.

Any part of a portable tank, including fittings, gaskets and pipe-work, which can be expected normally
to come into contact with the refrigerated liquefied gas carried shall be compatible with that
refrigerated liquefied gas.

Contact between dissimilar metals which could result in damage by galvanic action shall be avoided.

The thermal insulation system shall include a complete covering of the shell(s) with effective
insulating materials. External insulation shall be protected by a jacket so as to prevent the ingress of
moisture and other damage under normal carriage conditions.

When a jacket is so closed as to be gas-tight, a device shall be provided to prevent any dangerous
pressure from developing in the insulation space.

Portable tanks intended for the carriage of refrigerated liquefied gases having a boiling point below
minus (-) 182 °C at atmospheric pressure shall not include materials which may react with oxygen or
oxygen enriched atmospheres in a dangerous manner, when located in parts of the thermal insulation
when there is a risk of contact with oxygen or with oxygen enriched fluid.

Insulating materials shall not deteriorate unduly in service.

A reference holding time shall be determined for each refrigerated liquefied gas intended for carriage
in a portable tank.
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