Running a generator in your home could be fatal. More than 200 people have died from carbon monoxide poisoning. Toxic fumes spewed out by a generator.

One home generator can emit one hundred times more carbon monoxide than a car. We wanted to know... how fast does it happen? We were shocked by how quickly a home became a deathtrap.

It happens a lot in Wisconsin and all over the country. In April of 2006, a woman died in her apartment when carbon monoxide filled her living space. Her power had been shut off.

Then in November, two men died on a hunting trip when their heater filled the small cabin with the same toxic gas.

Jerry Roush survived. "All my nice friends. And nobody will ever go up there again, I don't think."

Carbon monoxide is called the silent killer. It's tasteless, odorless and colorless. But it kills. Fast.

Brookfield Firefighter Matt Erdmann explained the early symptoms of poisoning. "A headache, to extreme nausea, to extreme dizziness, lethargy, and eventually it puts your brain to sleep permanently."

And that's if you're not already asleep.

Generators used the wrong way can be to blame. We fired up a generator in the basement of an abandoned home in Brookfield. Firefighters plugged in digital carbon monoxide detectors in the front room and upstairs.

Firefighters carried their own calibrated detectors to make sure we stayed safe. The alarms on those detectors started shrieking, fast.

And after 15 minutes, the firefighters told us to get out of the house.

Reporter John Mercure and photographer Joe Eufemi suited up with breathing gear and oxygen tanks, making it safe to go back inside.
We were shocked at how much carbon monoxide was in the house.

Within 30 minutes, the levels were high: 230 parts per million. How bad is that?

"This would be lethal in one to two hours," Erdmann said.

And in the basement...an astounding 317 parts per million. High enough to kill. Without our special gear... We'd have gotten sick.

The message firefighters want to get out... Carbon monoxide detectors can save your life.

And never, ever, run a generator in the house. Don't even put it in an attached garage. The consequences could be deadly.

The Brookfield Fire Department has a limited number of carbon monoxide detectors for families in need. Many other fire departments run similar programs.

If you're concerned about levels of the gas in your house, call your local fire department.