NOVATO (KPIX 5) — A Novato man’s dog – obtained from a rescue organization – is being credited with returning the favor by saving his life after he was overcome with carbon monoxide poisoning.

Max, a 90-pound German Shepherd, seemed to know his owner, 80-year-old Jack Farrell was in serious trouble after a wall heater malfunctioned, filling their home with natural gas and carbon monoxide.

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Farrell said he was sleeping at the time and Max dragged him out of bed by his arm and down a hallway before Farrell was able to wake up and recover.

“Out here in the kitchen, I finally woke up wondering what the hell was going on because he had  hold of my arm,” said Farrell. “I’m bleeding like hell and that’s when I called 911.”

Novato Deputy Fire Chief Adam Brolan said by the time firefighters arrived, the carbon monoxide had reached deadly levels. “We took a reading of the environment and found 75 parts per million. To put that into perspective, we don our breathing gear at 25 parts per million.”

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“I’d be dead,” said Farrell. “He saved my life. Carbon monoxide is (bleeping) deadly man.”

“Jack could have died,” said Brolan.

Farrell got Max from German Shepherd Rescue of Northern California about a year ago.

Farrell was hospitalized briefly following the incident.

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PG&E determined the natural gas and the carbon monoxide leak were caused by debris and soot clogging a gas-powered wall heater in the home.