EPA Phase 2 fireplace inserts are designed to meet the most up-to-date standards for air quality as of July 2013. Fireplace inserts are wood-burning stoves that are seated inside an existing fireplace, with the vent pipe positioned so that smoke vents through a liner installed in the fireplace chimney. Most fireplace inserts are designed to burn wood; some burn pellets made of compressed wood, sawdust, cardboard, or other flammable materials.
Fireplace inserts are designed to enclose a fireplace, turning an open fire into a high-efficiency heating unit. The most up-to-date models emit more heat and use less fuel than open fires -- some will keep a fire burning from bedtime until morning on four or five pieces of split wood.
Open fireplaces typically lose up to 90 percent of heat through the chimney, according to the Environmental Protection Agency. A fireplace insert with a blower redirects most of that heat into the room. Fireplace insert units are essentially metal wood stoves that can be inserted into the open fireplace, venting from the top of the stove up the chimney. Most fireplace inserts come with a metal "apron" designed to cover the open space from the stove's edges to the fireplace facing for a clean, aesthetically pleasing look.
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Wood Burning and Air Pollution
Wood burning (or pellet burning) can be a high-efficiency, low-cost heating option, but air quality becomes a concern when using wood for daily heat. Smoke from fireplaces releases ash and other particulate matter into the air, which can lodge in the lungs of people and animals, causing respiratory distress and disease.
While open-hearth fireplaces have particulate emissions approaching 59 grams per hour, high-efficiency wood stoves have only 8.2 grams per hour of particulate emissions. Still, even EPA-approved, high-efficiency fireplaces can create particulate emissions in excess of state and federal air quality standards. Where air is completely stagnant or where atmospheric inversions trap air close to the ground, smoke can create pockets of harmful particles with the potential to harm public health, according to research reported by the Sierra Club, so some local communities -- like those in the San Joachin Valley in California -- are limiting use of open fireplaces or non-approved wood stoves.
EPA Phase 2 Regulations
The Clean Air Act was originally signed into U.S. law in 1970 and amended 20 years later. According to projections by the EPA, the Clean Air Act as amended has the capacity to save over 230,000 lives in 2020, once all air quality standards included in the bill are in effect for personal, governmental, and business interests.
EPA standards to date have been implemented in two phases in order to allow businesses and industrial producers to keep pace with the changes. Stoves that are Phase 1-certified meet standards implemented in July 1988; Phase 2-certified stoves meet more stringent air-quality emissions standards implemented in 1990.
EPA Phase 2 Inserts: "Qualified" vs. "Certified"
Wood stoves and fireplace inserts may be marked "qualified" as EPA Phase 2 standards without going through the certification process. In some cities, states, and municipalities, there are restrictions on the use of wood stoves that are not expressly certified, even if the model is theoretically qualified for certification. Make sure your insert of choice has been Phase 2-certified by the EPA to ensure your family's health and safety -- and to be certain that you can use your wood stove safely without legal repercussions.