9.  Before the Director grants a licence for the storage of petroleum in quantities exceeding 5 cases but not exceeding 12½ cases, the applicant shall provide within his premises in such a position as shall be approved by the Director one or more receptacles or storage bins measuring 1 metre, by 0.9 metre, by 0.9 metre, constructed of brickwork of a thickness of not less than 11 centimetres rendered inside with cement of a thickness of not less than 13 millimetres.