Two of the three people sickened by carbon monoxide at their New Ulm home remain hospitalized.
The Associated Press reports 93-year-old Arnold Schweiss and his 90-year-old wife, Velma, are in satisfactory condition at Hennepin County Medical Center. Their son was treated and released from New Ulm Medical Center on Monday.
According to the AP report, snow drifts around the home's exhaust and intake vents caused carbon monoxide to build up in their house and sickened the three.
Authorities say the incident is a good reminder for people to check their home's outdoor furnace vents and make sure they are clear of snow and ice.
Last month, two roommates from nearby rural Springfield were found dead from carbon monoxide poisoning.
The Minnesota Department of Health says because carbon monoxide has no color or taste it cannot be detected by human senses. Health officials say it can build up to dangerous concentrations indoors when fuel-burning devices are not properly vented, operated or maintained.
Health officials estimate that unintentional exposure to carbon monoxide accounts for 500 deaths in the United States each year and contributes to more than 2,000. The U.S. Consumer Product Safety Commission estimates 8,000 to 15,000 people are examined or treated in hospitals for non-fire related carbon monoxide poisoning.
Officials say homes with fire-burning appliances such as gas furnaces, water heaters, and fireplaces or homes with attached garages are more likely to have carbon monoxide problems than other homes.
The Department of Health says making sure all appliances and heating devices are properly vented, knowing the symptoms of carbon monoxide poisoning, and installing and maintaining carbon monoxide detectors in your home in accordance with state laws, are simple steps that can be taken to prevent carbon monoxide poisoning.