IMDG Code Compliance Centre

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IMDG Packaging & Tank Code Ready Reckoner

IMDG Code (42-24) Packaging, IBC, Large Packaging, Bulk Container & Portable Tank Instruction Matrix

This matrix is a working reference tool for practitioners already familiar with the Code. It is not a substitute for the IMDG Code itself — always check against your current Volume I before making a classification, packing or compliance decision.

1. Material letters & suffix modifiers

Material letter designations (6.1.2.6)

Material letters used across standard packagings, IBCs and Large Packagings
LetterMaterialApplicability
ASteel (all types and surface treatments)Standard Packagings, IBCs, Large Packagings
BAluminiumStandard Packagings, IBCs, Large Packagings
CNatural woodStandard Packagings, IBCs, Large Packagings
DPlywoodStandard Packagings, IBCs, Large Packagings
FReconstituted woodStandard Packagings, IBCs, Large Packagings
GFibreboardStandard Packagings, IBCs, Large Packagings
HPlastics material (including rubber & advanced cross-linked polymers)Standard Packagings, IBCs, Large Packagings
LTextileStandard Packagings, IBCs, Large Packagings
MPaper, multiwallStandard Packagings, IBCs, Large Packagings
NMetal (other than steel or aluminium)Standard Packagings, IBCs, Large Packagings
PGlass, porcelain or stonewareStandard Packagings only

System suffix modifiers

Letters that may follow a packaging / IBC / Large Packaging code
SuffixApplicable classDefinitionIMDG provisions
VStandard PackagingsSpecial packaging design-tested and marked in accordance with 6.1.5.1.7, distinct from standard 6.1.4 construction/testing (e.g. 4GV).6.1.2.4 / 6.1.5.1.7
WAll containersPackage/IBC of the same type as indicated by the code, manufactured to a different specification but considered equivalent.6.1.1.2 / 6.5.1.4.4
TStandard Packagings & Large PackagingsSalvage packaging, used to contain damaged, defective, leaking or non-conforming packages, or spilled/leaked dangerous goods, for recovery or disposal.6.1.2.4 / 6.1.5.1.11 (packagings); 6.6.5.1.9 (Large Packagings)
USpecial Packagings (Class 6.2 infectious substances only)Special packaging for Class 6.2 infectious substances, conforming to Chapter 6.3 design/testing — sits outside the general Chapter 6.1 T/V/W suffix system.6.3.5.1.6
ZIBCs (composite)Replaces the outer-packaging letter in a composite IBC code to indicate the material used for the outer casing.6.5.1.4.1.2

2. Standard packagings (6.1.4)

Drums, jerricans, boxes, bags & composite packagings
CodeKindMaterialHead / OpeningMax volumeMax net massProvisions
1A1DrumSteelNon-removable head450 L400 kg6.1.4.1
1A2DrumSteelRemovable head450 L400 kg6.1.4.1
1B1DrumAluminiumNon-removable head450 L400 kg6.1.4.2
1B2DrumAluminiumRemovable head450 L400 kg6.1.4.2
1N1DrumOther metal (non-steel/al)Non-removable head450 L400 kg6.1.4.3
1N2DrumOther metal (non-steel/al)Removable head450 L400 kg6.1.4.3
1H1DrumPlasticsNon-removable head450 L400 kg6.1.4.8
1H2DrumPlasticsRemovable head450 L400 kg6.1.4.8
1DDrumPlywoodStandard closed-end250 L400 kg6.1.4.5
1GDrumFibreStandard continuous tube core450 L400 kg6.1.4.7
2C1Wooden barrelNatural woodBung-type250 L400 kg6.1.4.6
2C2Wooden barrelNatural woodSlack-type removable250 L400 kg6.1.4.6
3A1JerricanSteelNon-removable head60 L120 kg6.1.4.4
3A2JerricanSteelRemovable head60 L120 kg6.1.4.4
3B1JerricanAluminiumNon-removable head60 L120 kg6.1.4.4
3B2JerricanAluminiumRemovable head60 L120 kg6.1.4.4
3H1JerricanPlasticsNon-removable head60 L120 kg6.1.4.8
3H2JerricanPlasticsRemovable head60 L120 kg6.1.4.8
4ABoxSteelSolid walling—400 kg6.1.4.14
4BBoxAluminiumSolid walling—400 kg6.1.4.14
4NBoxOther metal (non-steel/al)Solid walling—400 kg6.1.4.14
4C1BoxNatural woodOrdinary—400 kg6.1.4.9
4C2BoxNatural woodSift-proof walling—400 kg6.1.4.9
4DBoxPlywoodInterconnected sheets—400 kg6.1.4.10
4FBoxReconstituted woodBonded core—400 kg6.1.4.11
4GBoxFibreboardMulti-ply corrugated—400 kg6.1.4.12
4H1BoxExpanded plasticsLow-density structural—60 kg6.1.4.13
4H2BoxSolid plasticsRigid polymer walls—400 kg6.1.4.13
5H1BagWoven plasticsUnlined—50 kg6.1.4.16
5H2BagWoven plasticsSift-proof—50 kg6.1.4.16
5H3BagWoven plasticsWater-resistant—50 kg6.1.4.16
5H4BagPlastics filmSingle/multi-ply—50 kg6.1.4.17
5L1BagTextileUnlined—50 kg6.1.4.15
5L2BagTextileSift-proof—50 kg6.1.4.15
5L3BagTextileWater-resistant—50 kg6.1.4.15
5M1BagPaperMultiwall—50 kg6.1.4.18
5M2BagPaperMultiwall water-resistant—50 kg6.1.4.18
6HA1CompositePlastic liner in steel drumNon-removable head450 L400 kg6.1.4.19
6HA2CompositePlastic liner in steel boxRemovable top60 L400 kg6.1.4.19
6HB1CompositePlastic liner in aluminium drumNon-removable head450 L400 kg6.1.4.19
6HB2CompositePlastic liner in aluminium crateStructural protective60 L400 kg6.1.4.19
6HCCompositePlastic liner in wooden boxSolid outer wood60 L400 kg6.1.4.19
6HD1CompositePlastic liner in plywood drumCylindrical shield250 L400 kg6.1.4.19
6HD2CompositePlastic liner in plywood boxInterlocking perimeter60 L400 kg6.1.4.19
6HG1CompositePlastic liner in fibre drumCylindrical tube250 L400 kg6.1.4.19
6HG2CompositePlastic liner in fibreboard boxCorrugated perimeter60 L400 kg6.1.4.19
6HH1CompositePlastic liner in plastics drumPolymer outer cylindrical450 L400 kg6.1.4.19
6HH2CompositePlastic liner in solid plastics boxRigid external box60 L400 kg6.1.4.19

3. Intermediate Bulk Containers — IBC codes (6.5.5)

Metal, flexible, rigid plastics, composite, fibreboard & wooden IBCs
CodeOuter / code groupInner receptacle (if composite)Cargo stateDischarge modalityProvisions
11ASteel—SolidGravity6.5.5.1
11BAluminium—SolidGravity6.5.5.1
11NOther metal—SolidGravity6.5.5.1
21ASteel—SolidPneumatic / pressure (>10 kPa)6.5.5.1
21BAluminium—SolidPneumatic / pressure (>10 kPa)6.5.5.1
21NOther metal—SolidPneumatic / pressure (>10 kPa)6.5.5.1
31ASteel—LiquidPressure discharge6.5.5.1
31BAluminium—LiquidPressure discharge6.5.5.1
31NOther metal—LiquidPressure discharge6.5.5.1
13H1Flexible plastics (woven)—SolidGravity — uncoated, no liner6.5.5.2
13H2Flexible plastics (woven)—SolidGravity — coated6.5.5.2
13H3Flexible plastics (woven)—SolidGravity — with liner6.5.5.2
13H4Flexible plastics (film)—SolidGravity — plastics film6.5.5.2
13H5Flexible plastics (composite)—SolidGravity — composite plastics6.5.5.2
13L1Textile flexible—SolidGravity — uncoated, no liner6.5.5.2
13L2Textile flexible—SolidGravity — coated6.5.5.2
13L3Textile flexible—SolidGravity — with liner6.5.5.2
13L4Textile flexible—SolidGravity — dust-proof6.5.5.2
13M1Paper flexible—SolidGravity — multiwall6.5.5.2
13M2Paper flexible—SolidGravity — multiwall, water-resistant6.5.5.2
11H1Rigid plastics—SolidGravity6.5.5.3
11H2Rigid plastics—SolidGravity6.5.5.3
21H1Rigid plastics—SolidPneumatic / pressure (>10 kPa)6.5.5.3
21H2Rigid plastics—SolidPneumatic / pressure (>10 kPa)6.5.5.3
31H1Rigid plastics—LiquidPressure discharge6.5.5.3
31H2Rigid plastics—LiquidPressure discharge6.5.5.3
31HA1Steel casingRigid plasticsLiquidPressure discharge6.5.5.4
31HB1Aluminium casingRigid plasticsLiquidPressure discharge6.5.5.4
31HC1Wooden casingRigid plasticsLiquidPressure discharge6.5.5.4
31HD1Plywood casingRigid plasticsLiquidPressure discharge6.5.5.4
31HG1Fibreboard casingRigid plasticsLiquidPressure discharge6.5.5.4
31HH1Rigid polymer shellRigid plasticsLiquidPressure discharge6.5.5.4
31HA2Steel casingFlexible plasticsLiquidPressure discharge6.5.5.4
31HB2Aluminium casingFlexible plasticsLiquidPressure discharge6.5.5.4
31HC2Wooden casingFlexible plasticsLiquidPressure discharge6.5.5.4
31HD2Plywood casingFlexible plasticsLiquidPressure discharge6.5.5.4
31HH2Rigid polymer shellFlexible plasticsLiquidPressure discharge6.5.5.4
11GFibreboard—SolidGravity6.5.5.5
11CNatural wood—SolidGravity, integrated lining6.5.5.6
11DPlywood—SolidGravity, integrated lining6.5.5.6
11FReconstituted wood—SolidGravity, integrated lining6.5.5.6
Service-life notes such as “2-year” or “5-year” windows for flexible/rigid-plastics and composite IBCs reflect common industry replacement practice (linked to periodic testing intervals), not a single hard Code-mandated expiry — always confirm actual retest/requalification intervals against 6.5.4 and your competent authority’s approval conditions.

4. Large Packagings (6.6.4)

Rigid & flexible Large Packagings, maximum 3 m³ / 3,000 L
CodeTypeMaterialMax volumeProvisions
50ARigidSteel3 m³ (3,000 L)6.6.4
50BRigidAluminium3 m³ (3,000 L)6.6.4
50NRigidOther metal (non-steel/al)3 m³ (3,000 L)6.6.4
50HRigidPlastics3 m³ (3,000 L)6.6.4
51HFlexiblePlastics3 m³ (3,000 L)6.6.4

5. Bulk Containers — BK codes (6.9)

Sheeted, closed & flexible bulk containers
CodeContainer typeCapacity noteProvisions
BK1Sheeted bulk containerFreight-container type: Safety Approval Plate (CSC). Other bulk container types (skips, bins, swap bodies): competent authority approval.6.9.3 (freight-container type) / 6.9.4 (other bulk container types) & 4.3.1
BK2Closed bulk containerFreight-container type: Safety Approval Plate (CSC). Other bulk container types (skips, bins, swap bodies): competent authority approval.6.9.3 (freight-container type) / 6.9.4 (other bulk container types) & 4.3.1
BK3Flexible bulk container (FBC)Per 6.9.5.5.1(h)6.9.5 & 4.3.1.16
BK1 and BK2 aren’t tied to a single paragraph each — the applicable sub-section depends on the bulk container’s construction. 6.9.3 covers freight-container-type bulk containers (usable as BK1 or BK2); 6.9.4 covers other bulk container types such as skips, bins and swap bodies (also usable as BK1 or BK2).

6. Portable Tank Instructions T1–T22 (6.7.2)

Minimum test pressure, shell thickness, pressure-relief & bottom-opening provisions
CodeMin. test pressureMin. shell thickness (ref. steel) [6.7.2.4]Pressure relief [6.7.2.8]Bottom opening [6.7.2.6]
T11.5 barSee 6.7.2.4.2 (5 mm if D<1.80 m; 6 mm if D≥1.80 m)Normal (see Note a)Two serially mounted closures [6.7.2.6.2]
T21.5 barSee 6.7.2.4.2 (5 mm if D<1.80 m; 6 mm if D≥1.80 m)Normal (see Note a)Three serially mounted closures [6.7.2.6.3]
T32.65 barSee 6.7.2.4.2 (5 mm if D<1.80 m; 6 mm if D≥1.80 m)Normal (see Note a)Two serially mounted closures [6.7.2.6.2]
T42.65 barSee 6.7.2.4.2 (5 mm if D<1.80 m; 6 mm if D≥1.80 m)Normal (see Note a)Three serially mounted closures [6.7.2.6.3]
T52.65 barSee 6.7.2.4.2 (5 mm if D<1.80 m; 6 mm if D≥1.80 m)Safety relief valve with frangible disc in series [6.7.2.8.3]Not allowed for liquids (see Note b) [6.7.2.6.1]
T64 barSee 6.7.2.4.2 (5 mm if D<1.80 m; 6 mm if D≥1.80 m)Normal (see Note a)Two serially mounted closures [6.7.2.6.2]
T74 barSee 6.7.2.4.2 (5 mm if D<1.80 m; 6 mm if D≥1.80 m)Normal (see Note a)Three serially mounted closures [6.7.2.6.3]
T84 barSee 6.7.2.4.2 (5 mm if D<1.80 m; 6 mm if D≥1.80 m)Normal (see Note a)Not allowed for liquids (see Note b) [6.7.2.6.1]
T94 bar6 mm (min) [6.7.2.4]Normal (see Note a)Not allowed for liquids (see Note b) [6.7.2.6.1]
T104 bar6 mm (min) [6.7.2.4]Safety relief valve with frangible disc in series [6.7.2.8.3]Not allowed for liquids (see Note b) [6.7.2.6.1]
T116 barSee 6.7.2.4.2 (5 mm if D<1.80 m; 6 mm if D≥1.80 m)Normal (see Note a)Three serially mounted closures [6.7.2.6.3]
T126 barSee 6.7.2.4.2 (5 mm if D<1.80 m; 6 mm if D≥1.80 m)Safety relief valve with frangible disc in series [6.7.2.8.3]Three serially mounted closures [6.7.2.6.3]
T136 bar6 mm (min) [6.7.2.4]Normal (see Note a)Not allowed for liquids (see Note b) [6.7.2.6.1]
T146 bar6 mm (min) [6.7.2.4]Safety relief valve with frangible disc in series [6.7.2.8.3]Not allowed for liquids (see Note b) [6.7.2.6.1]
T1510 barSee 6.7.2.4.2 (5 mm if D<1.80 m; 6 mm if D≥1.80 m)Normal (see Note a)Three serially mounted closures [6.7.2.6.3]
T1610 barSee 6.7.2.4.2 (5 mm if D<1.80 m; 6 mm if D≥1.80 m)Safety relief valve with frangible disc in series [6.7.2.8.3]Three serially mounted closures [6.7.2.6.3]
T1710 bar6 mm (min) [6.7.2.4]Normal (see Note a)Three serially mounted closures [6.7.2.6.3]
T1810 bar6 mm (min) [6.7.2.4]Safety relief valve with frangible disc in series [6.7.2.8.3]Three serially mounted closures [6.7.2.6.3]
T1910 bar6 mm (min) [6.7.2.4]Safety relief valve with frangible disc in series [6.7.2.8.3]Not allowed for liquids (see Note b) [6.7.2.6.1]
T2010 bar8 mm (min) [6.7.2.4]Safety relief valve with frangible disc in series [6.7.2.8.3]Not allowed for liquids (see Note b) [6.7.2.6.1]
T2110 bar10 mm (min) [6.7.2.4]Normal (see Note a)Not allowed for liquids (see Note b) [6.7.2.6.1]
T2210 bar10 mm (min) [6.7.2.4]Safety relief valve with frangible disc in series [6.7.2.8.3]Not allowed for liquids (see Note b) [6.7.2.6.1]
Note a — “Normal” pressure relief: all provisions of 6.7.2.8 apply except 6.7.2.8.3 — a frangible disc in series with the spring-loaded device is not required (but is permitted unless otherwise prohibited).
Note b — “Not allowed” bottom openings apply when the substance is a liquid (6.7.2.6.1). When the substance is a solid at all temperatures under normal transport conditions, bottom openings conforming to 6.7.2.6.2 are authorised.