When an * authorised officer exercises a power under section 251 in relation to a * conveyance, he or she:
(a) may use such assistance as is necessary; and
(b) must search the conveyance in a public place or in some other place to which members of the public have ready access; and
(c) must not detain the conveyance for longer than is necessary and reasonable to search it and any container found in or on the conveyance; and
(d) may use such force as is necessary and reasonable in the circumstances, but must not damage the conveyance or any container found in or on the conveyance by forcing open a part of the conveyance or container unless:
(i) the person (if any) apparently in charge of the conveyance has been given a reasonable opportunity to open that part or container; or
(ii) it is not possible to give that person such an opportunity.