Abstract: This publication applies to steam reformers that are operated with natural gas, refinery off-gas, naphtha, and other light hydrocarbon streams. It specifically applies to large volume hydrogen production plants. This publication covers operation, maintenance, and certain design aspects of steam reformers relative to the potential safety hazards of the combustion process inherent to these units. Emphasis is placed on operational guidance and features that provide safeguards against such hazards such as furnace control philosophies, safety interlocks, and inspection routines. The publication is not intended to address the details of design, installation, and construction of steam reformers. The purpose of this publication is to inform and guide interested parties on the procedures and practices fundamental to combustion safety in the operation of steam reformers. This publication presents a baseline for safe reformer operation which, if followed, assures our customers that the hydrogen they receive from member companies has been produced according to accepted industry-wide safety guidelines.