SPECIALISTS IN TANK CONTAINERS

T-Codes - ISO Tank Container

The IMO type, like IMO Type 1, IMO Type 2, and IMO Type 5, was the original classification system for tank containers, but this was replaced by the “T” code system in 2001.

This is helpful because it includes more specific details such as test pressure, shell thickness, pressure relief setup, and outlet arrangement (both top and bottom). The “T” code identifies tank containers from T1 to T22, T50 and T75 tank container codes. And also defines the type of cargo each container can transport.

The “T” code system classification

All containers are classified according to the international standard ISO 6346. This code, also called the size type, indicates the length of the container and the type of container. For example, in code 22T4, the first 2 show a length of 20 feet, and the second 2 stand for 8.6 feet high. T4 indicates the type of container, as described in the table below.

All hazardous materials have a substance identification number or 'UN number' and a 'packing group.' With this combination, it is possible to determine which type of tank container is required for transport based on the regulations -IMDG Code, ADR, RID, and so on.[4] T1 through T3 label containers for non-hazardous products, and the codes from T4 onwards concern hazardous substances.

Refer to Chapter 4.2 of the ADR or IMDG code for full details of T codes and detailed provisions for individual substances.

Instructions for portable tanks specify the provisions applicable to a tank container when it is used to transport specific hazardous substances. T codes T1 to T22 specify the minimum test pressure and the minimum wall thickness of the tank container (referred to in mm reference steel) and the pressure relief valve and bottom opening provisions.

PORTABLE TANK INSTRUCTIONS

These portable tank instructions apply to liquid and solid substances of classes 3 to 9.
The general provisions of IMDG Section 4.2.1 and the requirements of Section 6.7.2

Portable Tank Minimum test Minimum shell thickness Pressure-relief Bottom opening
Instruction pressure (bar) (in mm-reference steel) requirements requirements
    (see IMDG 6.7.2.4) (see IMDG 6.7.2.8) (see IMDG 6.7.2.6)
 
T1 1,5 >or = 6mm normal int + ext
T2 1,5 >or = 6mm normal Int+ext+cap/blank
T3 2,65 >or = 6mm normal int + ext
T4 2,65 >or = 6mm normal Int+ext+cap/blank
T5 2,65 >or = 6mm normal + rupture disc not allowed
T6 4 >or = 6mm normal int + ext
T7 4 >or = 6mm normal Int+ext+cap/blank
T8 4 >or = 6mm normal not allowed
T9 4 6 mm normal not allowed
T10 4 6 mm normal + rupture disc not allowed
T11 6 >or = 6mm normal Int+ext+cap/blank
T12 6 >or = 6mm normal + rupture disc Int+ext+cap/blank
T13 6 6 mm normal not allowed
T14 6 6 mm normal + rupture disc not allowed
T15 10 >or = 6mm normal Int+ext+cap/blank
T16 10 >or = 6mm normal + rupture disc Int+ext+cap/blank
T17 10 6 mm normal Int+ext+cap/blank
T18 10 6 mm normal + rupture disc Int+ext+cap/blank
T19 10 6 mm normal + rupture disc not allowed
T20 10 8 mm normal + rupture disc not allowed
T21 10 10 mm normal not allowed
T22 10 10 mm normal + rupture disc not allowed 
T23 Depending on product  Depending on product  Depending on product  Depending on product 
T50 Depending on gas  Depending on gas  Depending on gas  Depending on gas 
T75 Depending on gas(frozen) Depending on gas(frozen)  Depending on gas(frozen)  Depending on gas(frozen)