Natural gas furnaces not only heat your home, they also produce a lot of pollution. Even modern high-efficiency condensing furnaces produce significant amounts of corrosive acidic condensation and unhealthy levels of nitrogen oxides, carbon monoxide, hydrocarbons and methane. These emissions are typically vented into the atmosphere and end up polluting our soil, water and air. Scientists have developed an affordable add-on technology that removes more than 99.9% of acidic gases and other emissions to produce an ultraclean natural gas furnace. This acidic gas reduction, or AGR, technology can also be added to other natural gas-driven equipment such as water heaters, commercial boilers and industrial furnaces.