The Crop Residues (Restrictions on Burning) Regulations 1991

3.  No crop residue may be burned unless–

(a) the area to be burned is surrounded by a fire-break, which borders on that area and which, in the case of cereal straw or cereal stubble, shall be at least 10 metres wide and in any other case at least 5 metres wide;

(b) any building, structure or other thing mentioned in paragraph 4(b) or (c) below which lies within the area to be burned is surrounded by a fire-break of the relevant width referred to in sub-paragraph (a) above which borders on any crop residues which are to be burned; and

(c) in the case of any land (“intervening land”) between a fire-break to be established in accordance with sub-paragraph (a) or (b) above and any other land or any building, structure or other thing mentioned in paragraph 4(b), (c) or (d) below which lies within the relevant distance there mentioned of the area to be burned or, as the case may be, of any crop residues within that area–

(i) the intervening land is cleared of all crop residues, or

(ii) all crop residues on the intervening land are incorporated into the soil before burning takes place.