INpolis, IN – Indinapolis Star – Seven people were sent to a hospital Thursday night for treatment of carbon monoxide exposure suffered in a Near-Eastside house, Indianapolis firefighters said.

A natural-gas furnace that had been started for the first time during the winter was being checked as a potential source.

Firefighters were sent to the house in the 200 block of North State Avenue about 9 p.m., after a report of an odor of gas in the house, said Indianapolis Fire Department Battalion Chief Robert McClain. Firefighters found the level of carbon monoxide inside the house so high that they needed to put on breathing equipment.

There were five adults and two children in the house. Firefighters said a woman and the children collapsed on the house’s front porch when they were removed. All seven were sent to Wishard Memorial Hospital for treatment.

The residents had moved in two days earlier and had just started the furnace in the basement, McClain said.

Firefighters said they measured the carbon monoxide level in the house’s basement at 1,100 parts per million, with 30 to 50 parts per million considered a safe level.