Method of use of a centrifugal dividerS
23. The method of using a centrifugal divider shall be as follows–
(a)the centrifugal divider shall be levelled prior to use;
(b)the centrifugal divider and pans shall be clean;
(c) Sample mixing
an empty pan shall be placed under each spout of the centrifugal 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 and any other particles in the sample pass into the pans;
(f)the motor shall be switched off;
(g)the two pans containing seed and any other particles shall be removed and replaced by empty ones;
(h)the contents of both pans removed during the procedure specified in sub paragraph (g) shall be poured together into the centre of the hopper, the seed and any other particles being allowed to blend as they flow in. The procedures specified in sub paragraphs (e) to (g) shall be repeated;
(i)the procedure specified in sub paragraph (h) shall be repeated twice to mix the sample thoroughly;
(j) Sample reduction
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 and any other particles in the second pan is of at least the minimum weight prescribed in paragraph 26 of Part II of this Schedule for a sample, it may be used as a submitted sample. If the weight of seed in the second pan is greater than the minimum weight prescribed in paragraph 26 of Part II of this Schedule for a 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 and any other particles have passed shall then be set aside. If the weight of seed and any other particles in the other pan is still greater than the minimum weight prescribed in paragraph 26 of Part II of this Schedule for a sample, the sample may be used as a submitted sample intact or it may be reduced further using the procedures specified in sub paragraphs (k) to (m);
(n)if the weight of seed and any other particles in either of the two pans referred to either in sub paragraph (j) or (m) is less than the minimum weight prescribed in paragraph 26 of Part II of this Schedule for a 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 during the procedure specified in sub paragraph (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 weights shall be produced;
(s)the procedures specified in sub paragraphs (q) and (r), when repeated, constitute the process of continuous halving, and shall be repeated using whichever sub-sample is appropriate until a sufficient sample is obtained in one pan, which, when added to the seed and any other particles set aside during the procedure specified in sub paragraph (p), produces a submitted sample;
(t) Obtaining more than one submitted sample
when two submitted samples are required from one composite sample, one composite sample of at least twice the minimum weight prescribed in paragraph 26 of Part II of this Schedule for a sample shall be obtained using the procedures specified in sub paragraphs (c) to (i) and (j) to (s) as appropriate. The composite sample shall then be divided into two parts by passing it once through the centrifugal divider; and
(u)when three submitted samples are required from one composite sample, one composite sample of at least three times the minimum weight prescribed in paragraph 26 of Part II of this Schedule for a sample shall be obtained using the procedures specified in sub paragraphs (c) to (i) and (j) to (s), as appropriate. A submitted sample shall then 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 two submitted samples shall be obtained from this residue of the composite sample by following the procedure specified in sub paragraph (t).
Commencement Information
I1Sch. 5 para. 23 in force at 1.7.2005, see reg. 1(1)