4.—(1) All the documents referred to in paragraphs 1 and 2 shall be kept—
(a)in the case of any road tanker, by the operator thereof either at the premises from which the tanker operates or at his principal place of business within Great Britain; and
(b)in the case of any tank container, by the operator thereof at the address within Great Britain from which the deployment of the tank container is controlled.
(2) It shall be sufficient compliance with sub-paragraph (1)(b) above in circumstances where the operator of the tank container is not its owner, if—
(a)authenticated copies of the documents concerned are kept at the operator’s place of business; or
(b)the documents concerned are readily available from the owner of the tank container.
(3) Where the operator of a road tanker or tank container changes, the previous operator shall, insofar as he is required to keep any document at an address in Great Britain in accordance with sub-paragraph (1) above, give any such document to the new operator.
(4) Where either of the procedures referred to in paragraph 2(4) has been used, it shall be sufficient compliance with sub-paragraph (1) in respect of the report referred to in paragraph 2(1)(c) if that report is kept by the operator concerned in a computer at the appropriate place specified in sub-paragraph (1) above; and without prejudice to the generality of sub-paragraph (3) above, if the operator changes in circumstances where the report referred to in paragraph 2(1)(c) is kept in a computer in accordance with this sub-paragraph, the previous operator shall provide the new operator with the information contained in that report in written form.