DECATUR - Area firefighters are receiving calls from residents who smell fumes in their homes and are concerned about the presence of carbon monoxide.

That concern is justified, two fire chiefs said Thursday.

"We've had four or five calls from people using kerosene or other types of heaters that aren't vented properly," said Warrensburg Fire Chief Keith Hackl. "People smell fumes and call us. They want to have it checked out."

Hackl said firefighters using carbon monoxide monitors have found some homes with nine parts per million of the gas, but the level has to be 30 parts per million or higher to be of real danger.

Decatur Fire Chief Matt Sekosky said he has seen news reports this week of people using their natural gas stoves to heat homes that have no power or having portable electric generators in their basements or enclosed garages. He said those reports make him nervous.

"If you use a stove to provide heat you need to have your house well ventilated," Sekosky said. "But if you open the house enough to do that, you're defeating the purpose of using the stove and dissipating the heat. We recommend not using stoves for heat."

Decatur Fire Marshal Lyle Meador said two St. Louis men got sick last week in their home when they used a charcoal grill to heat the closed house and were overcome by carbon monoxide.

A Glen Carbon couple was running a generator last week in an enclosed garage, and the odorless, colorless carbon monoxide fumes entered the house, Sekosky said. The wife died, and the husband was hospitalized in critical condition, he said.

Meador said he was amazed recently at two talks he gave to senior citizen groups to find people who told him they believed the only way carbon monoxide was generated was from vehicle exhaust.

Anytime LP gas, natural gas, wood, charcoal or kerosene are burned the deadly gas results, Meador said. Cracked heat exchangers on furnaces and caps not properly aligned on the top of water heaters are common ways the gas can seep into houses, he said.

As of Jan. 1, state law requires any house with a natural gas-fired appliance to have a carbon monoxide detector installed within 15 feet of the sleeping area, Meador said.

The detectors can be battery-operated or plug-in models with a battery backup, with lithium battery-powered units being among the best, Meador said.

Ron Ingram can be reached at ringram@herald-review.com or 421-7973.