T7 PORTABLE TANK INSTRUCTION T7
The general provisions of section 4.2.1 and the requirements of section 6.7.2 shall be met.
Minimum test pressure 4 bar
Minimum shell thickness (reference steel) 5 mm for tanks up to 1.80 m diameter and for larger tanks carrying solids of packing group II or III; 6 mm otherwise.
Pressure-relief provisions Normal
Bottom opening provisions 3 shut-off devices required.
Alternatives permitted T8, T9, T10, T11, T12, T13, T14, T15, T16, T17, T18, T19, T20, T21, T22

Special packing provisions:

TP
The degree of filling prescribed in 4.2.1.9.2 shall not be exceeded.
TP2
The degree of filling prescribed in 4.2.1.9.3 shall not be exceeded.
TP3
The maximum degree of filling (in %) for solids transported above their melting points and for elevated temperature liquids shall be determined in accordance with 4.2.1.9.5.
TP4
The degree of filling shall not exceed 90% or, alternatively, any other value approved by the competent authority (see 4.2.1.16.2).
TP6
To prevent the tank bursting in any event, including fire engulfment, it shall be provided with pressure-relief devices which are adequate in relation to the capacity of the tank and to the nature of the substance transported. The device shall also be compatible with the substance.
TP7
Air shall be eliminated from the vapour space by nitrogen or other means.
TP8
The test pressure for the portable tank may be reduced to 1.5 bar when the flashpoint of the substances transported is greater than 0°C.
TP13
Self-contained breathing apparatus shall be provided when this substance is transported, unless no self-contained breathing apparatus, as required by SOLAS regulation II-2/19 (II-2/54), is on board.
TP16
The tank shall be fitted with a special device to prevent under-pressure and excess pressure during normal transport conditions. This device shall be approved by the competent authority. Pressure-relief provisions are as indicated in 6.7.2.8.3 to prevent crystallization of the product in the pressure-relief valve.
TP17
Only inorganic non-combustible materials shall be used for thermal insulation of the tank.
TP18
Temperature shall be maintained between 18°C and 40°C. Portable tanks containing solidified methacrylic acid shall not be reheated during transport.
TP24
The portable tank may be fitted with a device located, under maximum filling conditions, in the vapour space of the shell to prevent the build-up of excess pressure due to the slow decomposition of the substance transported. This device shall also prevent an unacceptable amount of leakage of liquid in the case of overturning or entry of foreign matter into the tank. This device shall be approved by the competent authority or its authorized body.
TP28
A portable tank having a minimum test pressure of 2.65 bar may be used if it is shown that a test pressure of 2.65 bar or less is acceptable according to the test pressure definition in 6.7.2.1.
TP30
This substance shall be transported in insulated tanks.
TP33
The portable tank instruction assigned for this substance applies for granular and powdered solids and for solids which are filled and discharged at temperatures above their melting point and which are cooled and transported as a solid mass. For solids which are transported above their melting point, see 4.2.1.19.
TP36
Fusible elements in the vapour space may be used on portable tanks.
TP39
The portable tank instruction T4 may continue to be applied until 31 December 2018.
TP41
The 2.5 year internal examination may be waived or substituted by other test methods or inspection procedures specified by the competent authority or its authorized body, provided that the portable tank is dedicated to the transport of the organometallic substances to which this tank special provision is assigned. However this examination is required when the conditions of 6.7.2.19.7 are met.