Of the entire NFPA 110 standard, 8.4 entitled “Operational Inspection and Testing” is the section that is the most often read, misquoted, misunderstood and misinterpreted, the result of lifting and quoting material from it out of context. Taking this section in its entirety provides a clear and simple guideline for inspecting and testing the entire Emergency Power Supply System (EPSS). It is only when the AHJ uses a portion of 8.4, or adds their spin, that things get a little foggy.