Narrative:

We taxied from the gate to runway 10C in pit. We taxied up to and stopped short of what appeared to be an ILS critical hold short line for runway 10C. The red sign said '10C apr.' the captain and I had a short discussion about the ILS critical area and he wanted me to ask ground control if we could continue past it. We were waiting for the 2-minute engine warm-up. I asked ground if we could 'continue up to and short of runway 10C' and they said that was approved and to contact tower when ready. I asked the captain if he was ready to go and he said yes. I contacted tower to inquire while moving some charts around and the captain started taxiing. After I asked for clearance; and before they had responded; the captain became aware that he had just taxied onto runway 10C and stopped the aircraft. Before anything else was said we were cleared for takeoff by the tower. The signage at runway 10C was very misleading but we should have had better knowledge of the meaning of the various hold short bars. I have personally reviewed this information. It may be worth the time to review the signage at runway 10C. I also believe that I should not have moved charts around at such close proximity to a runway; even thought I believed we were not going to enter an active runway. I will be more diligent with that in the future. I also believe that one of the critical factors in this incident was the other pilot's personal distraction due to a small run-in he had with a gate agent prior to boarding. This seemed to largely distract him from his duties. I also had a hard time keeping him involved in operating the rest of the flight normally because this runway incident even further distracted him; to the point that it was difficult to hold a conversation.

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Original NASA ASRS Text

Title: An Embraer Jet Flight Crew was confused by the labels of the hold short line at the taxiway passing perpendicular to the west end of Runway 10C at PIT.

Narrative: We taxied from the gate to Runway 10C in PIT. We taxied up to and stopped short of what appeared to be an ILS critical hold short line for runway 10C. The red sign said '10C APR.' The Captain and I had a short discussion about the ILS critical area and he wanted me to ask Ground Control if we could continue past it. We were waiting for the 2-minute engine warm-up. I asked ground if we could 'continue up to and short of runway 10C' and they said that was approved and to contact Tower when ready. I asked the Captain if he was ready to go and he said yes. I contacted Tower to inquire while moving some charts around and the Captain started taxiing. After I asked for clearance; and before they had responded; the Captain became aware that he had just taxied onto Runway 10C and stopped the aircraft. Before anything else was said we were cleared for takeoff by the Tower. The signage at Runway 10C was very misleading but we should have had better knowledge of the meaning of the various hold short bars. I have personally reviewed this information. It may be worth the time to review the signage at Runway 10C. I also believe that I should not have moved charts around at such close proximity to a runway; even thought I believed we were not going to enter an active runway. I will be more diligent with that in the future. I also believe that one of the critical factors in this incident was the other pilot's personal distraction due to a small run-in he had with a gate agent prior to boarding. This seemed to largely distract him from his duties. I also had a hard time keeping him involved in operating the rest of the flight normally because this runway incident even further distracted him; to the point that it was difficult to hold a conversation.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.