Factors affecting lighting fixture operating temperature, fixture life, and subsequent suitability for classified areas

The variables that affect the operating temperature and fixture life of industrial lighting fixtures are discussed. Specifying fixtures that will be safe and reliable in process industry environments is considered. A checklist is provided for the specifier and end user to effectively manage the variable factors that affect fixture operating temperature, subsequent stability for classified areas, and ballast life. The checklist considerations are: determine area classification by class, group, and division; check limitations; specify to ensure environmental suitability; determine the worst-case ambient temperature of the installation, considering both climate and heat contributed by process equipment; minimize installation and maintenance pitfalls; such as relamping fixtures with a lamp with which the fixture was not tested or approved; and design, specify, and standardize, keeping worst-case conditions in mind