You can't see it or smell it, but it can be deadly. Three people were poisoned by the "silent killer", or carbon monoxide, over a span of 48 hours.
On Saturday, Rochester fire crews responded to a call about an employee who collapsed at the Gingerbread House Bakery.
When they arrived, the CO detectors in the building were beeping, indicating elevated carbon monoxide levels.
Firefighters evacuated the building and found that three other employees also showed signs of CO poisoning. One employee was taken to Mayo Clinic - Saint Marys to be examined.
"At the Gingerbread House, what we had was a malfunctioning appliance. In that case, the employees and the owner of the property assume that their appliances are working properly, that it's venting properly. But because of a mechanical failure, unknown to the employees or the employer, we had carbon monoxide that was built up in that environment," said Rochester Fire Deputy Chief Vance Swisher.
Just under 48 hours later, firefighters were dispatched to another carbon monoxide poisoning incident at Northern Turkey Farm on Simpson Road Southeast, just outside of Rochester.
Five employees were doing routine barn sanitizing with a gas powered power washer when one of them became sick. There were elevated carbon monoxide levels in the barn and two of the employees were transported to Mayo Clinic - Saint Marys for treatment.
"We want to make sure we take all steps appropriately to make sure we do not put ourselves in a position where we're getting exposed to high levels of carbon monoxide. In this case, if they had a door open that probably would have helped or relieved the issue where we wouldn't see the buildup that we saw today," said Swisher.
It's important to be mindful of carbon monoxide in your home or business during the winter months, because these types of events are more prevalent this time of year.
"So at anytime during this time of year, we're trying to conserve energy. So one of the biggest concerns we have, whether or not it's an industrial process or just our normal heating, we need to be worried about the buildup of carbon monoxide inside of a structure. Anything from a residential home to a place of business," said Swisher.
Symptoms of carbon monoxide poisoning mimic a common cold, food poisoning, the flu and other ailments. If you or a loved one begins to exhibit these symptoms, you should dial 911 and seek medical attention.