The women, one in her 20s and one in her 50s, were pulled from the house on 114th Street in Ozone Park just before 8 a.m. Monday.
They were listed in critical condition at Jamaica Medical Center, where they were being treated in the hyperbaric chamber.
Carbon monoxide readings were as high as 500 parts per million when firefighters arrived at the house. They were able to quickly vent the house, and the levels dropped to normal.
A faulty boiler is believe to have caused the leak.
Fire officials said there were no carbon monoxide alarms in the house.
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