This is so named because practically the whole of the between-deck space under the shelter-deck is regarded in British tonnage measurement as an open space.
Oku kubizwe ngenxa yokuba ukusetyenziswa kokuphelela okuphakathi komgangatho wethuba ongaphantsi kokhuselo mgangatho luthunyelwa eBritish umthwalo umetwa njengokuvulwa kwesithuba.