The Methylated Spirits Regulations 1987

Regulation 15(2)

SCHEDULE CONDITIONS TO WHICH DENATURANTS, MARKERS AND DYES MUST CONFORM

Wood Naphtha

(1) The wood naphtha must, to the satisfaction of the Commissioners, possess such properties as to render a mixture of one part of the naphtha with nineteen parts of spirits of wine unfit for use as a beverage.

(2) The wood naphtha must contain not less than 72 per cent by volume of methyl alcohol.

Crude Pyridine

(1) Crude pyridine should consist of pyridine bases, and should not be more deeply coloured than a mixture of 2 millilitres of deci-normal iodine with one litre of water.

(2) It should mix readily and completely with spirits and should give a clear or only slightly opalescent solution when mixed with twice its volume of water.

(3) 10 millilitres of a 1 per cent solution in water should produce immediately a distinct crystalline precipitate on vigorous shaking after the addition of 5 millilitres of an aqueous solution of cadmium chloride containing 5 grammes of the anhydrous fused salt in 100 millilitres and an abundant separation of crystals within ten minutes.

(4) A white precipitate should be formed when 10 millilitres of a 1 per cent solution in water are mixed with 5 millilitres of Nessler’s reagent.

(5) 1 millilitre of crude pyridine dissolved in 10 millilitres of distilled water should require not less than 9.5 millilitres of normal sulphuric acid for neutralisation, using Congo Red paper as indicator.

(6) 100 millilitres slowly heated under the conditions laid down for Benzol for Motor Fuel by the British Engineering Standards Association (B.S. Specification 2 D 15) should give a distillate of at least 50 millilitres at a temperature of 140 degrees C and of 90 millilitres at 160 degrees C.

Mineral Naphtha (Petroleum Oil)

The mineral naphtha (petroleum oil) must be of a specific gravity of not less than 0.800 and must possess the characteristic odour and taste of commercial paraffin oil used for burning purposes.

Methyl Violet Dye (Colour Index No. 680)

The Methyl Violet dye must be in the form of small crystals readily and completely soluble in 95 per cent alcohol.

Tertiary Butyl Alcohol and “Bitrex”

Tertiary butyl alcohol and “Bitrex” must be of normal commercial quality.