# Fertilisers (Sampling and Analysis) Regulations (Northern Ireland) 1996, Chapter 1.: PREPARATION OF THE SAMPLE FOR ANALYSIS


ALL OPERATIONS CONNECTED WITH THIS PROCEDURE SHOULD BE CARRIED OUT AS QUICKLY AS POSSIBLE TO MINIMISE ABSORPTION OR LOSS OF WATER. CARE SHOULD BE TAKEN DURING GRINDING THAT THE TEmperature of the fertiliser does not rise above 45°C to avoid loss of volatile constituents. Grinding beyond the fineness required must in all cases be avoided.
Grinding and sieving
5.1 The procedure in 5.1.1 should be followed except when a grinding machine is not available, in which case 5.1.2 is applicable.
5.1.1 Grind the final sample until all the sample has passed through, or for the specified time, depending on the type of grinder (4.1). To check that the grinding has been adequate, sieve a small portion of the ground sample through a 0.5 mm sieve (4.3) and discard it. If the whole of this portion does not pass the sieve, return the remainder of the sample to the grinder and repeat the grinding until satisfactory grinding is achieved.
5.1.2 Sieve the whole final sample through the 0.5 mm sieve (4.3). Grind the residue on the sieve, using the pestle and mortar (4.2), until all the material passes through the sieve. Carefully mix the sample.
5.2 Place the prepared sample in a clean container (4.4) and seal it until required for analysis.
5.3 Before taking each test portion for analysis, the whole sample must be well mixed. Form the material into a flattened cone and using a spatula take the required test portion at random in small increments.
5.4 If the sample contains foreign matter which cannot be ground this shall be removed, weighed and allowed for in the results of the analysis. This material shall be retained and if possible its nature recorded.

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Source: https://www.legislation.gov.uk/nisr/1996/513/schedule/2/part/II/chapter/1. (the official version)
Page: https://openlegislation.uk/fertilisers-sampling-and-analysis-regulations-northern-ireland-1996/schedule-2/part-II/chapter-1.
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.