Great Barrington fire officials say the teens were found Saturday and brought to a hospital. They are expected to make full recoveries.
Officials say they found potentially lethal carbon monoxide levels in the home, between 500 and 800 parts per million.
Authorities say they determined the source to be a gas furnace and plugged chimney.
Firefighters also say there were no working carbon monoxide detectors in the home. They urged all homeowners to install detectors for the odorless gas.
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