3.—(a) In the case of solid fertilisers the aggregate sample shall, if necessary, be reduced to not less than 2 kg, or 4 kg for ammonium nitrate fertilisers sampled for testing in accordance with method 14 in Part I of Schedule 2, in the following manner:—
(i)the material shall be heaped to form a “cone”, which shall then be flattened and quartered. Two diagonally opposite quarters shall be rejected and the remainder shall then be mixed and the quartering and rejection continued as necessary; or
(ii)the reduction method effected by the use of a mechanical device.
(b)In the case of fluid fertilisers if the aggregate sample consists of approximately 2 litres this may be taken as the reduced sample. In all other cases the aggregate sample shall be thoroughly mixed and a quantity of at least 2 litres transferred immediately into a clean dry vessel of suitable material.