10.2.1 Where
                                 longitudinal underdeck girders are fitted at deck level to support
                                 the hatch covers the requirements of this sub-Section are to be complied
                                 with.
                              
                              
                              
                            
                           
                           
                           
                              
                              
                              10.2.2 The
                                 girders may take the form of open or closed box sections and these
                                 should align with webs on the transverse bulkheads to form a continuous
                                 ring structure.
                              
                              
                              
                            
                           
                           
                           
                              
                              
                              10.2.3 The
                                 girders are, in general, to be continuous throughout the container
                                 hold area, including the engine room where this is situated between
                                 container holds.
                              
                              
                              
                            
                           
                           
                           
                              
                              
                              10.2.4 Special
                                 attention is to be given to the intersection of the girders with transverse
                                 box girders and the integration into the fore end, aft end and machinery
                                 space structures.
                              
                              
                              
                            
                           
                           
                           
                              
                              
                              10.2.5 Where
                                 girders are integrated into the cross-deck strips, inserts plates
                                 with integral gussets are to be incorporated. The inserts are to have
                                 a thickness not less than that of the girder top and bottom plates,
                                 as appropriate. The radius of main hatchway openings in way of ends
                                 of hatch girders at upper deck level is, in general, to be not less
                                 than 20 per cent of the width of the cross-deck strip indicated inPt  4, Ch  8,  4.4 Cross decks 4.4.5 with a minimum of 250 mm.