"Process heater" means, for purposes of Part 217, an enclosed combustion device that burns gaseous or liquid fuels only and that indirectly transfers heat to a process fluid or a heat transfer medium other than water. This term does not include pipeline heaters and storage tank heaters that are primarily meant to maintain fluids at a certain temperature or viscosity.
Ill. Admin. Code tit. 35, § 211.5195
Added at 33 Ill. Reg. 13326, effective August 31, 2009