ADR 2025 4.3.4.1.1
Tank Code Decoder
Decode all four parts of a tank code: type, pressure, openings and safety devices.
How this is calculated
How a tank code is structured
An ADR tank code has four parts, always in the same order: the physical state the tank is designed for, its minimum calculation pressure, the arrangement of its openings, and its safety devices. Reading them in order is the whole technique.
The code describes what a tank is. It does not by itself tell you whether that tank may carry a particular substance — that comes from the ADR entry for the goods.
- 1
First character — type
L is for substances in the liquid state, including solids carried molten. S is for substances in the solid state, powdery or granular.
- 2
Second part — minimum calculation pressure
Either G, meaning the general minimum calculation pressure under 6.8.2.1.14, or a value in bar: 1.5, 2.65, 4, 10, 15 or 21.
- 3
Third character — openings
A is bottom filling or discharge with two closures; B is bottom filling or discharge with three closures; C is top filling or discharge with only cleaning openings below liquid level; D is top filling or discharge with no openings below liquid level.
- 4
Fourth character — safety devices
V is a breather device without flame-propagation protection, or a tank not resistant to explosion pressure shock. F adds flame-propagation protection or explosion-pressure-shock resistance. N is no breather device and not hermetically closed. H is a hermetically closed tank.
Worked example
The tank code L4BN.
- L — liquids, including solids carried molten
- 4 — 4 bar minimum calculation pressure
- B — bottom filling or discharge with three closures
- N — no breather device, not hermetically closed
Result: A 4 bar liquid tank with three bottom closures and no breather device, which is not hermetically closed.
What this tool does not decide: The decoder validates and explains a code. It does not determine which tank code a substance requires, and it does not decode the (M) and (+) markers that appear against some Table A entries.
Carry ADR Driver Pro with you
Revise by route, use the offline reference and keep practical driver tools close at hand.
