7. If the silo has retaining walls–
(a)the retaining walls shall be capable of withstanding minimum wall loadings calculated on the assumptions and in the manner indicated by paragraph 15.6.1 to 15.6.3 of the Code of Practice on Buildings and Structures for Agriculture published by the British Standards Institution and numbered BS 5502: Part 22: 1993;
(b)the silo shall at no time be loaded to a depth exceeding the maximum depth consistent with the design assumption made in respect of the loadings of the retaining walls; and
(c)notices shall be displayed on the retaining walls in accordance with paragraph 9.2 of the Code of Practice referred to in sub-paragraph (a) above.