10.18.11 Hydrostatic release units, other than
                           disposable hydrostatic release units, should be serviced:
                        
                        
                        
                        
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                                 .1 at intervals not exceeding 12 months, provided
                                 where in any case this is impracticable the Administration may extend
                                 this period to 17 monthsfootnote;
                                 
                              
                              
                              
                            
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                                 .2 at a servicing station which is competent to
                                 service them, maintains proper servicing facilities and uses only
                                 properly trained personnel.