Petroleum (Consolidation) Act 1928

5 The bath having been raised to the proper temperature, the cup shall be placed on a level surface in a good light and the oil to be tested shall be poured into it until the level of the liquid just reaches the point of the gauge which is fixed in the cup. Before a, test is begun the temperature of the oil shall be determined and shall be brought to approximately 60 degrees Fahrenheit. The cover, with the slide closed, shall then be put on to the cup and pressed down so that its edge rests on the rim of the cup, and the cup shall -be placed into the bath or heating vessel, every care being taken to avoid wetting the sides of the cup with the oil. The thermometer in the fid of the cup has been adjusted so as to have the correct immersion when the brass collar of the thermometer is properly seated, and its position shall not in any circumstances be altered. When the cup has been placed in the proper position, the scale of the thermometer faces the operator.