A B733 CREW; AFTER LNDG AT MDW; TAXIED ACROSS A RWY THEY WERE TO HOLD SHORT OF.

Narrative

WE CLRED RWY AT TXWY B. TWR TOLD US CONTACT GND. GND CTL CLRED US TO TAXI DOWN RWY 13L AND HOLD SHORT OF RWY 22R. I READ BACK CLRNC TO GND; BUT DID NOT SPECIFICALLY SAY TO THE CAPT 'HOLD SHORT OF RWY 22R' I FELT CERTAIN HE HAD HEARD THE SAME THING I DID. ACCOMPLISHED FLAPS UP; CLEAN UP AND MADE ON GND CALL TO COMPANY. (WE HAD REQUESTED AIR AND ELECTRIC STANDING BY ON OUR IN-RANGE CALL AS WE HAD AN APU PROB EARLIER.) SHORTLY AFTER I COMPLETED ON GND CALL AS WE WERE GETTING CLOSER TO RWY 22R COMPANY CALLED AND ASKED IF WE STILL NEEDED AIR AND ELECTRIC OR HAD THE APU STARTED. I DON'T KNOW IF I SAID 'I'M OFF' OR IF I JUST ANSWERED THE COMPANY CALL; BUT AT ANY RATE; I BECAME DISTR TALKING TO THEM JUST AS WE APCHED THE INTXN. I SAW THAT WE WERE XING A RWY AND I LOOKED BOTH DIRECTIONS TO CLR AND I SAW THE CAPT LOOK BOTH DIRECTIONS. I BELIEVE THE RWYS 22 WERE ONLY BEING USED FOR TKOFS AT THIS TIME -- ALL LNDGS WERE BEING DONE ON RWYS 31. THERE WAS A COMPANY ACFT HOLDING SHORT OF RWY 22L IN FRONT OF US ALSO GOING TO THE GATES (HOLDING ON RWY 13L). AS I CAME BACK ON FREQ I HEARD GND SAY 'I THOUGHT I ASKED YOU TO HOLD SHORT OF RWY 22R; BUT THAT'S OK; JUST HOLD SHORT WHERE YOU ARE.' IN RETROSPECT: I KNEW WE WERE XING A RWY; BUT I'M NOT SURE I WAS SITUATIONALLY AWARE THAT IT WAS RWY 22R AND FURTHERMORE; EVEN HAD I BEEN AWARE IT WAS; I THINK I PROBABLY ASSUMED WE WERE CLRED TO CROSS WHILE I WAS TALKING TO COMPANY. NOTE: WHEN WE INITIATE GND CALL WE DO IT AT OPPORTUNE TIME. I SHOULD NOT HAVE ALLOWED MYSELF TO BECOME DISTR JUST BECAUSE THEY CALLED US. I WISH THEY HAD JUST HAD AIR AND ELECTRICITY STANDING BY INSTEAD OF CALLING US. GND CTL IS BUSY ENOUGH WITHOUT BEING DISTR. SUPPLEMENTAL INFO FROM ACN 531465: AS I APCHED RWY 22R; I SAW ANOTHER COMPANY ACFT AHEAD OF ME HOLDING SHORT OF RWY 22L; WHICH WAS BEING USED FOR DEPS. THIS UNFORTUNATELY CONFIRMED IN MY MIND THAT MY INSTRUCTION HAD ALSO BEEN TO HOLD SHORT OF RWY 22L. I CAREFULLY CHKED RWY 22R BEFORE I CROSSED IT FOR TFC. I STILL HAD A SLIGHT DOUBT THAT MAYBE MY INSTRUCTION HAD BEEN TO HOLD SHORT OF THE R; BUT GND WAS BUSY; SO I DIDN'T CONFIRM IT. BIG MISTAKE. I SIMPLY SHOULD HAVE CONFIRMED MY CLRNC; ESPECIALLY WITH THE FO OFF THE FREQ.