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Category B substances outside special areas and category C substances:in al 
areas 
(5) Subject to such surveillance and approval by the authorized or appointec 
surveyor aS may be deemed necessary by the Government of the Party, the 
Master of a ship shall, with respect to a Category B substance outside specia 
areas or a Category C substance in all areas, ensure compliance with the 
following: 
(a) If a tank is partially unloaded or unloaded but not cleaned, ar 
appropriate entry shall be made in the Cargo Record Book. 
(b) If the tank is to be cleaned at sea: 
(i) the cargo piping system serving that tank shall be drained and 
an appropriate entry made in the Cargo Record Book ; 
(ii) the quantity of substance remaining in the tank shall not exceed 
the maximum quantity which may be discharged into the sea for that 
substance under Regulation 5(2) (c) of this Annex outside Speerat areas 
in the case of Category B substances, or under Regulations 5 (3) (c) and 
5(9)(c) outside and within special areas respectively in the case of 
Category C substances. An appropriate entry shall be made in the Cargo 
Record Book ; 
(iii) where it is intended to discharge the quantity of substance 
remaining into the sea the approved procedures shall be complied with, 
and the necessary dilution of the substance satisfactory for such a dis- 
charge shall be achieved. An appropriate entry shall be made in the 
Cargo Record Book; or 
(iv) where the tank washings are not discharged into the sea, if any 
internal transfer of tank washings takes place from that tank an appro- 
priate entry shall be made in the Cargo Record Book ; and 
(v) any subsequent discharge into the sea of such tank washings shall 
be made in accordance with the requirements of Regulation 5 of this 
Annex for the appropriate area and Category of substance involved. 
(ec) If the tank is to be cleaned in port: 
(i) the tank washings shall be discharged to a reception facility and 
an appropriate entry shall be made in the Cargo Record Book; or 
(ii) the tank washings shall be retained on board the ship and an 
appropriate entry shall be made in the Cargo Record Book indicating 
the location and disposition of the tank washings. 
(d) If after unloading a Category C substance within a special area, any 
residues or tank washings are to be retained on board until the ship is 
outside the special area, the Master shall so indicate by an appropriate entry 
in the Cargo Record Book and in this ease the procedures set out in Regu- 
lation 5(3) of this Annex shall be applicable. 
Category B substances within special areas 
(6) Subject to such surveillanee and approval by the authorized or appointed 
surveyor as may be deemed necessary by the Government of the Party, the 
Master of a ship shall, with respect to a Category B substance within a special 
area, ensure compliance with the following : 
(a) If a tank is partially unloaded or unloaded but not cleaned, an appro- 
priate entry shall be made in the Cargo Reeord Book. 
(b) Until that tank is cleaned every subsequent pumping or transfer 
operation earried out in connection with that tank shall also be entered in 
the Cargo Record Book. 
(c) If the tank is to be washed, the effluent from the tank washing opera- 
tion, which shall contain a volume of water not less than 0.5 per cent of the 
total volume of the tank, shall be discharged from the ship to a reception 
facility until the tank, its pump and piping system are empty. An appro- 
priate entry shall be made in the Cargo Record Book. 
(aq) If the tank is to be further cleaned and emptied at sea, the Master 
shall: 
(i) ensure that the approved procedures referred to in Regulation 
5(8) (e) of this Annex are complied with and that the appropriate en- 
tries are made in the Cargo Record Book ; and 
(ii) ensure that any discharge into the sea is made in accordance 
with the requirements of Regulation 5(8) of this Annex and an appro- 
priate entry is made in the Cargo Record Book. 
