The Fertilisers (Sampling and Analysis) Regulations 1991

Incremental samples

1.  Incremental samples of approximately equal sizes shall be taken at random throughout the whole sampled portion in the following manner:—

(a) in the case of solid fertilisers in containers—

(i) having selected the required number of containers for sampling in accordance with paragraph 2(a) of Part III of this Schedule, part of the content of each selected container shall be taken as the incremental sample, except in the case of material to which sub-paragraph (iv) of this paragraph applies;

(ii) where necessary, each selected container shall be emptied and worked up with a shovel seperately and one shovelful taken as the incremental sample;

(iii) when the material is of a siutable nature the incremental sample may be taken from each selected container by means of a sampling spear or by divider;

(iv) when the material is so packed or of such a nature that a shovel or spear or divider cannot be used, or where the content of the container does not exceed 1 kg, the whole container shall be taken as the incremental sample;

(v) where the fertiliser is in a coarse or lumpy condition incremental samples shall be taken in accordance with sub-paragraph (ii) or (iv) of this paragraph as appropriate. These shall be crushed immediately and the whole passed through a sieve with meshes 31.8 mm square;

(vi) where the fertiliser consists of bulky material, uneven in character and likely to get matted together, each selected package shall be emptied seperately and the matted portions torn up and the whole of the contents of each package shall be thoroughly mixed. The incremental samples shall then be taken in accordance with sub-paragraphs (ii) or (iv) of this paragraph as appropriate;

(b) in the case of loose solid fertilisers—

(i) an imaginary division shall be made of the sampled portion into a number of approximately equal parts, corresponding to the number of incremental samples required in accordance with Table 2 in Part VI of this Schedule and at least one incremental sample shall be taken at random from each of these parts;

(ii) when sampling is being carried out while the material comprising the sampled portion is in motion, the incremental samples shall be taken from the approximately equal parts as required in sub-paragraph (b)(i) of this paragraph;

(iii) when a sampling spear is used the sample shall be taken at an angle to the base of the heap;

(iv) where the fertiliser is in a coarse or lumpy condition, or consists of bulky material, uneven in character and likely to get matted together, the incremental samples shall be taken in accordance with the relevant provisions of paragraph 1(a)(v) or 1(a)(vi), as appropriate;

(v) where it is not possible to comply with the requirements of paragraph 1 of Part III of this Schedule when sampling fertilisers in bulk, the sampling should be carried out when the sampled portion is loaded or unloaded. In this case samples shall be taken from the randomly selected notional parts, as defined in sub-paragraph (b)(i) of this paragraph, while these are being moved;

(c) in the case of fluid fertilisers in containers each containing not more than 100 litres, the number of containers to be selected shall be taken in accordance with Table 3 in Part VI of this Schedule and

(i) where the containers each contain not more than 1 litre the entire contents of the selected containers shall be transferred into a clean dry vessel of suitable material;

(ii) where the containers each contain more than 1 litre and not more than 100 litres the selected containers shall be well shaken or the contents agitated or otherwise treated to ensure uniformity. An approximately equal proportion of fluid shall be then be taken immediately from each of the selected containers and transferred into a clean dry vessel of suitable material;

(d) in the case of fluid fertilisers in containers each containing more than 100 litres—

(i) when a consignment is being withdrawn from the container and there is a tap in the outlet pipe from which it is suitable to draw a sample, a quantity of not less than 4 litres shall be drawn from the tap (after first withdrawing sufficient to remove any residues in the pipe) into a clean dry vessel of suitable material, made up of portions not less than 0.5 litres and of approximately equal size taken at regular intervals; otherwise

(ii) if the liquid is homogenous, about 1 litre shall be drawn from a convenient outlet in the container (after first withdrawing sufficient to remove any residues in the outlet) into a clean dry vessel of suitable material, or

(iii) if the liquid is not homogenous, the contents shall be well stirred or otherwise agitated and sampling shall then proceed as in sub-paragraph (ii), but

(iv) if it is not possible to make the liquid homogenous, in the manner described in sub-paragraph (iii), or if the inspector considers that the procedure in sub-paragraphs (i), (ii) and (iii) may not be appropriate, the contents shall be sampled by lowering an open tube (which must be long enough to reach the bottom of the container) perpendicularly into the container. One or both ends of the tube shall then be closed and the contents transferred into a clean dry vessel of suitable material. If sampling by tube is impracticable, portions shall be taken from various levels of the container with a sampling bottle so as to obtain a quantity fairly representative of the whole. The appropriate process shall be repeated until a quantity of not less than 4 litres has been withdrawn;

(v) where a sampled portion consists of two or more containers, incremental samples of approximately equal size shall be taken from each, drawn in the manner described in sub-paragraphs (i), (ii), (iii) or (iv), as appropriate, and shall be placed in a clean dry vessel of suitable material.