SALT LAKE CITY — Family members of two Colorado residents who died after inhaling carbon monoxide from a propane heater while camping in Utah have filed a wrongful death suit against a popular outdoor gear company.

Steven Dowdy, 28, and Darian Thomlinson, 10, were using a Coleman PowerMate propane heater and a Coleman propane lantern to warm themselves in a tent on rainy night in southeast Cache County. They were participating in a paintball tournament with family and friends when they were found dead June 21, 2009.

Dowdy's wife, Amber, and Darian's parents Mark and Theresa Thomlinson, of Grand Junction, Colo., filed the suit against Coleman Company Inc., in U.S. District Court in Salt Lake City.

In addition to retaining Provo-based Howard, Lewis & Peterson, the families hired Minnesota attorney Mark Stageberg, who has sued Coleman 15 times over radiant propane heaters, winning an $8 million verdict in one case.

"They keep killing people with these heaters and they won't do a recall to get them off the market," he said.

Coleman stopped selling the PowerMate models in 2006, but Stageberg said 1.7 million of them remain in use. "People do not understand there's a serious risk to them for taking one of these heaters inside a camper or tent," he said.

The two Colorado families have struggled since the deaths, Stageberg said. Steven and Amber Dowdy were married only eight months when he died. He had a 3-year-old daughter from a previous relationship.

"It's been extremely difficult for the Thomlinsons," Stageberg said. "(Darian) was just a charming, wonderful young lady."

The Utah lawsuit claims Coleman knew the products were defective and failed to warn customers of the amount of ventilation needed to safely use them.

"Long before the PowerMate 5017 and the propane lantern were sold, the defendant was fully aware that users of its propane heaters and propane lanterns were using the products within enclosures without appropriate ventilation and were, as a result, dying from carbon monoxide poisoning," the suit states.

Coleman spokeswoman Delaina Lee said the company, based in Wichita, Kan., does not comment on pending litigation.

Numerous lawsuits have been filed against Coleman the past 20 years. Stageberg said he is aware of at least 90 deaths, counting only those reported to the Consumer Product Safety Commission and the company itself. About a third resulted in litigation, he said.

"No doubt there were many more not reported," he said.

In Stageberg's six cases that went to trial, juries sided with Coleman in three of them. Others were settled out of court.

Federal consumer protection officials told the company the heaters were deficient but Coleman failed to correct them, the lawsuit says.

"Defendant has known for many years that the propane radiant heaters of its competitors in the marketplace have a built-in safety shut device that extinguishes the heaters before they emit deadly levels of carbon monoxide. Defendant has known for many years that the propane heaters of its competitors have not resulted in dozens of carbon monoxide deaths and injuries like the Coleman heaters."

The suit seeks an unspecified amount for economic, non-economic and punitive damages.