A man was found dead yesterday morning, apparently of carbon monoxide poisoning, in the Kensington rowhouse he shared with his girlfriend, police said. Gerald Creighton, 56, was discovered by his brother shortly after 10 a.m., said Sgt. Tom Walsh of the East Detective Division.

Creighton's girlfriend, Deborah Moffitt, 53, was lying semiconscious in the same front room. She was taken to the Hospital of the University of Pennsylvania, where she was listed in critical condition last night. Fire marshal's investigators and officials from Philadelphia Gas Works found an obstructed exhaust duct that had enabled the carbon monoxide to collect inside, Walsh said.

Kathy Selser, the couple's next-door neighbor, said she had run to help after hearing Creighton's brother screaming outside the front door. Selser said she called 911 upon seeing Creighton sitting upright in a chair, his face ashen.

Moffitt's eyes were open, Selser said, but she was unable to respond to questions. The block was evacuated for about two hours while investigators checked adjacent residences for elevated carbon monoxide levels.

- Larry King