# The Seed (Registration, Licensing and Enforcement) (England) Regulations 2002, Paragraph 31: Centrifugal Divider


The method of using a centrifugal divider shall be as follows—
(a) the divider shall be levelled prior to use;
(b) the divider and pans shall be clean;
Sample Mixing
(c) an empty pan shall be placed under each spout of the divider;
(d) the entire composite sample shall be poured into the centre of the hopper;
(e) the motor shall be operated so that the seed passes into the pans;
(f) the motor shall be switched off;
(g) the two pans containing seed shall be removed and replaced by empty ones;
(h) the contents of both pans removed at (g) shall be poured together into the centre of the hopper, the seed being allowed to blend as it flows in. The procedures specified in sub-paragraphs (e), (f) and (g) shall be repeated;
(i) the procedure specified in sub-paragraph (h) shall be repeated to mix the sample thoroughly;
Sample Reduction
(j) before reduction, the composite sample shall have been thoroughly mixed using the procedures specified in sub-paragraphs (c) to (i). The contents of one of the two receiving pans shall then be set aside. If the seed in the second pan is of at least the prescribed minimum weight for a submitted sample of a particular species of seed, it may be used as the submitted sample. If the weight of seed in the second pan is greater than the appropriate prescribed minimum weight for a submitted sample, it may be reduced using the procedures specified in sub-paragraphs (k) to (m);
(k) empty pans shall be placed under the spouts;
(l) the contents of the second pan shall be poured into the hopper and the procedures specified in sub-paragraphs (e) and (f) shall be repeated;
(m) the contents of one of the two pans into which the seed has passed shall then be set aside. If the weight of seed in the other pan is still greater than the appropriate minimum prescribed weight for a submitted sample, it may be submitted intact or it may be reduced further using the procedures specified in sub-paragraphs (k) to (m);
(n) if the weight of seed in either of the two pans at either (j) or (m) is less than the appropriate prescribed minimum weight for a submitted sample, the procedures specified in sub-paragraphs (o) to (s) shall be used;
(o) empty pans shall be placed under the spouts;
(p) the contents of one of the pans shall be set aside, the contents of the other pan shall be poured into the centre of the hopper and the procedures specified in sub-paragraphs (e) and (f) shall be repeated;
(q) one receiving pan and its contents shall then be removed and replaced with an empty pan; the other pan, with its contents, shall be left in place;
(r) the contents of the pan removed at (q) shall be poured into the centre of the hopper and the procedures specified in sub-paragraphs (e) and (f) shall be repeated so that two sub-samples of different weight shall be produced;
(s) the procedures specified in sub-paragraphs (q) and (r) above, when repeated, constitute the process of continuous halving, and shall be repeated using whichever sub-sample is appropriate until sufficient seed is obtained in one pan, which when added to the seed set aside at (p) produces a submitted sample of at least the appropriate prescribed minimum weight;
Obtaining more than one submitted sample
(t) two submitted samples shall be obtained from a composite sample by first obtaining a sample of at least twice the appropriate prescribed minimum weight for a submitted sample, using the procedures specified in sub-paragraphs (c) to (i) and (j) to (s) as appropriate, and then dividing it into two parts by passing it once through the divider;
(u) when three submitted samples are required from one composite sample, one sample, of at least the appropriate prescribed minimum weight for a submitted sample, shall be extracted using the procedures specified in sub-paragraphs (c) to (i) and (j) to (s) as appropriate. All portions of seed which have been set aside shall then be recombined and the residue of the composite sample so obtained shall be subject to the procedure specified in sub-paragraph (t).

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Source: https://www.legislation.gov.uk/uksi/2002/3176/schedule/5/paragraph/31 (the official version)
Page: https://openlegislation.uk/seed-registration-licensing-and-enforcement-england-regulations-2002/schedule-5/paragraph-31
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.