A detailed evaluation of furnace heating systems is presented. Topics of discussion include application guidelines for both gas fired and electrically heated furnaces. Heating system selection considers operating temperature@ processing atmosphere and heating method (radiant or convective heating) along with heating system orientation within the furnace chamber. The evaluation consists of a comparison of operating costs@ environmental considerations and lifetime maintenance costs of the various systems. Systems to be evaluated consist of alloy radiant tubes (single ended@ U-tube@ etc.)@ ceramic radiant tubes (single ended and U-tubes) and a variety of electrical element designs. Actual case studies of the various heating systems are presented with respect to maintenance and operating costs.