▁T ots uka ▁to ▁Sh ō n and ai ▁opened ▁on ▁August ▁ 2 8 , ▁ 1 9 9 9 . ▁ ▁All ▁stations ▁began ▁to ▁include ▁al phan umeric ▁codes ▁" B ## " ▁just ▁before ▁the ▁start ▁of ▁the ▁ 2 0 0 2 ▁FIFA ▁World ▁Cup , ▁which ▁occurred ▁at ▁the ▁same ▁time ▁as ▁the ▁sub way ▁line ' s ▁ 3 0 th ▁anni versary . ▁Every ▁station ▁was ▁identified ▁by ▁a ▁flag ▁representing ▁each ▁of ▁the ▁countries ▁that ▁competed ▁in ▁the ▁tournament . ▁Begin ning ▁July ▁ 1 , ▁ 2 0 0 3 , ▁a ▁women - only ▁car ▁is ▁offered ▁on ▁week day ▁m orn ings ▁between ▁ 5 : 2 0 ▁and ▁ 9 : 0 0 . ▁ ▁On ▁June ▁ 1 5 , ▁ 2 0 0 6 , ▁the ▁b ureau ▁announced ▁that ▁the ▁service ▁connecting ▁Line ▁ 1 ▁and ▁Line ▁ 3 ▁would ▁be ▁officially ▁named ▁the ▁" Blue ▁Line " ▁in ▁prepar ation ▁for ▁the ▁opening ▁of ▁a ▁second ▁sub way ▁line ▁known ▁as ▁the ▁Green ▁Line . ▁ ▁Platform ▁screen ▁doors ▁began ▁to ▁be ▁installed ▁in ▁all ▁stations ▁in ▁January ▁ 2 0 0 7 ; ▁this ▁required ▁stopping ▁positions ▁to ▁be ▁changed ▁at ▁some ▁stations , ▁including ▁Od or iba . ▁Az am ino ▁became ▁the ▁first ▁station ▁to ▁use ▁those ▁doors ▁in ▁April ▁ 2 0 0 7 , ▁and ▁the ▁doors ▁were ▁full ▁us able ▁by ▁September ▁of ▁that ▁year . ▁A TO ▁operation ▁began