ANNEX
AMENDMENTS TO THE REVISED SPECIFICATIONS FOR THE DESIGN,
OPERATION AND CONTROL OF CRUDE OIL WASHING SYSTEMS
(RESOLUTION A.446(XI) AS AMENDED BY RESOLUTION A.497(XII))
Paragraph 4.2.10 of the Annex to resolution A.446(XI) as amended by resolution A.497(XII) is replaced by the following:
"4.2.10 To confirm the effectiveness of the crude oil washing system and stripping system, the crude oil washing operation should be witnessed to the satisfaction of the Administration.
(a) For ships that comply with regulation 13F(3), the crude oil washing operations are to be carried out using the approved crude oil washing equipment and as specified in the approved Operations and Equipment Manual. For at least one tank of a group of tanks of similar configuration, the Administration should:
(i) Confirm the operation of the stripping system by observing the monitoring devices and monitoring the oil level (by dipping or other means) during bottom washing.
(ii) Monitor the proper operation of the washing machines with particular reference to supply pressure, cycle times and machine function.
On completion of washing and final draining, the tanks are to be hand dipped, as close as practical to the forward end, centre and aft end in each tank and a record of these dips should be made in the COW Manual. An Administration may require an internal examination as described in subparagraph (b)(i) of this section, or by an alternative method acceptable to the Administration, if deemed necessary.
(b) For ships other than those complying with regulation 13F(3), where fitted with cargo tanks intended to be used in certain circumstances as ballast tanks, the following requirements apply in addition to those specified in paragraph (a) of this section:
(i) To ensure that the tank is essentially free of clingage and deposits, the Administration may require that the cleanliness of the tank be confirmed by a visual inspection made by entering the tanks after a crude oil washing but prior to any water rinse which may be specified in the Operations and Equipment Manual. If the tanks cannot be gas freed for safe entry of the surveyor, an internal examination should not be conducted and the stripping test specified in 4.2.10(b)(ii) will be acceptable.
In this case, the bottom of the tank to be inspected may be flushed with water and stripped in order to remove any heel of crude oil before gas-freeing for entry, if the flushing procedure is adopted, a similar but unflushed tank must be used for the test specified in (ii) below.
