A receptacle used for medium scale storage must be constructed and maintained in accordance with the following requirements—
(a) the construction of the receptacle must be sturdy; and
(b) the inner construction of the receptacle must—
(i) be made from, or be lined with, plywood or close joined timber or another suitable non-sparking material; and
(ii) not include exposed iron or steel; and
(iii) be spark proof; and
(c) the receptacle must be fitted with an effective locking system and must be kept securely locked, except when it is required to be open for purposes relating to its use or management; and
(d) the interior of the receptacle must be kept clean and free of extraneous materials.