Carbon monoxide is a colorless, odorless gas that can be produced by burning any fuel. The initial symptoms are flu-like, including headache, fatigue, shortness of breath, nausea and dizziness. Exposure to high levels of carbon monoxide can cause death.
Each year, CO poisoning from heating systems and water heaters kills about 160 people in the U.S. Many of these tragedies could be prevented by having a professional check your heating system and water heater annually for CO leaks.