1.1.1 In 2003, the Marine Environment Protection
                           Committee adopted the Revised guidelines and specifications for pollution
                           prevention equipment for machinery space bilges of ships (resolution MEPC.107(49)). The main purpose
                           of this revision of the specifications of oil filtering equipment
                           was to improve their capability of treating emulsified oil.
                           
                        
                        
                        
                      
                     
                     
                     
                        
                        
                         
                           1.1.2 The present Guidelines have been developed
                           to provide further assistance for upgrading systems installed on board
                           ships prior to 1 January 2005, and of which oil filtering equipment
                           was approved under resolution MEPC.60(33).
                           
                        
                        
                        
                      
                     
                     
                     
                        
                        
                         
                           1.1.3 It has been recognized that the best measure
                           to prevent pollution resulting from oily bilge water is installation
                           of Integrated Bilge Water Treatment System (IBTS) in accordance with MEPC.1/Circ.642 as may be amended. IBTS
                           prevents generation of oily bilge water. Although it may not be easy
                           or practicable to fit complete IBTS on existing ships, pre-cleaning
                           of oily bilge water, e.g., provision of a primary tank between bilge
                           wells and bilge tank, should be seriously considered in order to remove
                           impurities in bilge through surfacing or sedimentation, which is an
                           effective way of preventing clogging of bilge separators.