Carbon monoxide is extremely dangerous, as a leak in your home could prove fatal. The gas is scented for this reason, so if you ever smell gas, you should take care of the problem immediately. The best thing to do in this situation is turn off the gas. After the gas is off, call a professional to check out your appliance. Even when there is no issue, it’s important to have your furnace and water heater inspected regularly. This can prevent future problems. Installing a carbon monoxide detector is also a smart decision.