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HMRC internal manual

Oils Technical Manual

Tables: table L- oils we control because they are not marked

The possibility that marking might be an appropriate control can also be considered.

Typical Product Used for Has no marker because Covered by legislation Our controls are covered in:
AVTUR (aviation turbine fuel) or JET A1 or any military jet fuel and their variations for helicopters (AVCAT, amongst others) Aviation turbine fuel for jet engines To maintain purity of the fuel for technical and for safety reasons Hydrocarbon Oil Marking Regulations, 2002 Section 6 AVTUR and its variants will run diesel engines. See Notice 179A (Traders who supply AVTUR are required to register under the RDCO scheme).
Marine Gas Oil Sea going vessels It is accepted that the fuel is effectively going for export by leaving the UK - we encourage marking but there is no requirement to do so   Some is marked. Fuel that is re-landed should be marked, see Notice 263. (The control of Marine Fuels is under review).
Solvents, hydraulic fluids, trans-former oils, and oils for other industrial purposes, where they are incorporated into ‘other’ goods such as paints. Tied Oils or oils ‘put to certain use’ being purposes other than for road fuel or heating fuel use. It is accepted that is the oil is being incorporated into other products, and markers may have a detrimental effect on the end product Hydrocarbon Oil Duties Act 1979, Section 9 Tied OIL traders have to be approved - see Notice 184A. The disposal of waste Tied oil is also controlled.
Fuel oil or furnace fuel Dark Oil used to be used to fuel marine oil-fired boilers, but this fuel is now rarely burnt for emission reasons. Dark oil is often old or impure oil that should not be used as ‘rebated’ oil because its colour impedes the identification of fiscal dyes Prohibited for sale as vehicle fuel by the Hydrocarbon Oil Marking Regulations 2002, Section 17