A Gas Clean Up System (GCUS) has been designed, built and installed for the new tritium handling facility at Atomic Weapons Establishment (AWE), Aldermaston. The system is in the process of being commissioned and once this is complete and the facility is operational, it will be used for the removal of hydrogen isotopes from gaseous waste arisings within the facility and concentrating them in waste packages. The system also provides a depression for the sources of these waste arisings, particularly the inert gas gloveboxes, as part of the contamination containment within the facility. This paper describes the details of various sub-systems within the GCUS and their engineering, construction, installation and testing.