A good owner label answers two questions: what is actually in the can, and which vehicle or equipment is that reserve intended for?

Permanent marks and contents labels do different jobs

The UN/manufacturer marking identifies the container and its approved design. Your own label identifies the current contents. Neither should be mistaken for the other.

Use the pump grade where it is known

German labels include E5, E10, B7, B10 and XTL. Reusing the exact grade on the can is more precise than writing only “petrol” or “diesel”.

Keep the original marking readable

Do not cover UN codes, production information, article numbers or other permanent data. Those details may later be needed to identify the can, its age or compatible accessories.

Check again before pouring

ADAC points out that small fuel-can spouts can fit different vehicle filler necks. A final check of the can label, vehicle and fuel grade can prevent an expensive mistake.

A label is not an approval: the can must still be suitable for the fuel and the vehicle must be approved for the actual grade.

Frequently asked questions

Is “petrol” enough as a label?

A more precise grade such as E5 or E10 can be useful when the actual fuel is known and the vehicle is approved for it.

Can a sticker cover the UN marking?

No. Permanent container markings should remain readable; an owner-added label is only an addition.

Is can colour a reliable label?

No. Colour conventions vary. Use readable markings and a known contents history.

Sources for this guide

The following authorities and documents were used for this guide. Where rules change, the current original source takes precedence.

  1. Section 13 of Germany’s 10th Federal Immission Control Ordinance – fuel labelling [German]Bundesministerium der Justiz / Gesetze im InternetGerman E5, E10, B7, B10 and XTL labels and vehicle-compatibility notices
  2. Questions and answers on dangerous-goods packaging and UN marks [German]Bundesanstalt für Materialforschung und -prüfung (BAM)Meaning, limits and interpretation of UN packaging marks
  3. Wrong fuel in the tank: petrol and diesel mix-ups [German]ADACMisfuelling risks and the particular mix-up risk when using small fuel-can spouts