A family member found Ethel Rosskopf unresponsive on the kitchen floor and a vehicle with its engine running in the garage of the home at Knollwood Road and Meadow Drive, Passaic County Prosecutor Camelia M. Valdes and Totowa Police Chief Carmen Veneziano said in a joint announcement.
Rosskopf was pronounced dead at the scene.
Authorities found the carbon monoxide level in the home at 200 parts per million, as opposed to the ordinary reading of 0 parts per million.
"There were no signs of foul play at the scene, and there is no danger to the public," Valdes and Veneziano said.
Firefighters ventilated the home while the Passaic County Sheriff's Bureau of Criminal Identification responded to collect evidence.
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