scope:

This Interim Defence Standard specifies the requirements for a lubricating oil primarily for use in two-stroke, water-cooled outboard motor. The oil may also be used in air-cooled two-stroke gasoline engine under the guidance of the appropriate design authority. The oil may either be used in neat form or in a fuel-oil mixture, depending on the equipment but, in the latter case, the fuel:oil ratio to be used in any engine shall be that recommended by relevant service instructions or, if these are not available, as recommended by the engine manufactures from -20ºC to +40ºC and may also be used beyond this range with adequate precaution.