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tre provided in accordance with Regulation 18 of this Annex, or where arrange- 
ments such as eductors involving the use of water additional to the washing 
water are not fitted, the Administration may accept 2 per cent. New oil tankers 
over 70,000 tons deadweight shall be provided with at least two slop tanks. 
(7) Slop tanks shall be so designed particularly in respect of the position 
of inlets, outlets, baffles or weirs where fitted, so as to avoid excessive turbulence 
and entrainment of oil or emulsion with the water. 
(3) (a) An oil discharge monitoring and control system approved by the 
Administration shall be fitted. In considering the design of the oil content 
meter to be incorporated in the system, the Administration shall have regard 
to the specification recommended by the Organization.’ The system shall be 
fitted with a recording device to provide a continuous record of the discharge 
in litres per nautical mile and total quantity discharged, or the oil content 
amd rate cf discharge. This record shall be identifiable as to time and date 
and shall be kept for at least three years. The oil discharge monitor and control 
system shall come into operation when there is any discharge of effluent into 
the sea and shall be such as will ensure that any discharge of oily mixture is 
automatically stopped when the instantaneous rate of discharge of oil exceeds 
that permitted by Regulation 9(1) (a) of this Annex. Any failure of this moni- 
toring and control system shall stop the discharge and be noted in the Oil Record 
Book. A manually operated alternative method shall be provided and may be 
used in the event of such failure, but the defective unit shall be made operable 
hefore the oil tanker commences its next ballast voyage unless it is proceed- 
ing to a repair port. Existing oil tankers shall comply with all of the provisions 
specified above except that the stopping of the discharge may -be performed 
manually and the rate of discharge may be estimated from the pump character- 
istic. 
(b) Effective oil/water interface detectors approved by the Administration 
shall be provided for a rapid and accurate determination of the oil/water 
interface in slop tanks and shall be available for use in other tanks where the 
separation. of oil and water is effected and from which it is intended to dis- 
charge effluent direct to the sea. 
(c) Instructions as to the operation of the system shall be in accordance with 
an operational manual approved by the Administration. They shall cover manual 
nus well aS automatic operations and shall be intended to ensure that at no 
time shall oil be discharged except in compliance with the conditions specified 
in Regulation 9 of this Annex.? 
(4) The requirements of paragraph (1), (2) and (8) of this Regulation 
shall not apply to oil tankers of less than 150 tons gross tonnage, for which 
the control of discharge of oil under Regulation 9 of this Annex shall be effected 
by the retention of oil on board with subsequent discharge of all contaminated 
washings to reception facilities. The total quantity of oil and water used for 
wishing and returned to a storage tank shall be recorded in the Oil Record 
Rook. This total quantity shall be discharged to reception faciilties unless 
adequate arrangements are made to ensure that any effluent which is allowed 
to be discharged into the sea is effectively monitored to ensure that the pro- 
visions of Regulation 9 of this Annex are complied with. 
(5) The Administration may waive the requirements of paragraphs (1), (2) 
and (3) of this Regulation for any oil tanker which engages exclusively on 
voyages both of 72 hours or less in duration and within 50 miles from the 
nearest land, provided that the oil tanker is not required to hold and does not 
hold an International Oil Pollution Prevention Certificate (1973). Any such 
waiver shall be subject to the requirement that the oil tanker shall retain on 
board all oily mixtures for subsequent discharge to reception facilities and to 
the determination by the Administration that facilities available to receive such 
oily mixtures are adequate. 
(6) Where in the view of the Organization equipment required by Regula- 
tion 9(1) (a) (vi) of this Annex and specified in sub-paragraph (3) (a) of this 
Regulation is not obtainable for the monitoring of discharge of light refined 
products (white oils), the Administration may waive compliance with such 
requirement, provided that discharge shall be permitted only in compliance 
1 Reference is made to Recommendations on International Performance Specifications for 
Qilv-Water Separating Equipment and Oil Content Meters adopted by the Organization by 
Resolution A.253( VII). 
2 Reference is made to “Clean Seas Guide for Oil Tankers,” published by the International 
tional Chanter ef Shipping and the Oil Companies International Marine Forum. 
