A firewall (also called a fire shield) can be used to reduce the safe distance between a stove and a wall. A wood stove can radiate heat for long periods and it will accumulate in materials that are too close. A standard design goal is to leave 2 or 3 feet of air between an uninsulated stove (or stovepipe) and any flammable materials (paint, wooden wall interiors, insulation, wooden or plastic trim, floors, etc). As a rule of thumb, if a nearby surface is too hot to rest your bare hand on, then it is too close to the stove. When properly designed and installed a firewall can reflect or dissipate heat from the stove, protecting the wall behind it, thus permitting the stove to be moved closer to the wall without creating a fire hazard. The installation guide or contractor can assist in determining the safety clearances around a stove with or without a firewall. For example, an asbestos fire shield installed with a one-inch air-gap behind and below it may permit the distance to the stove to be cut in half (i.e., 18 inches minimum, less if the stove design permits it).