The Rev H minimum wind, ice and earthquake loading requirements for a new or existing structure are based on reliability requirements. Reliability requirements are established by considering the consequences (risk) of failure of a structure depending on its use and location. For a communication structure, use is defined by the types of services provided by the equipment supported by the structure. Rev G had 3 categories of structures based on reliability requirements. Rev H now has 4 categories and has updated the terminology used to describe the categories from “Structure Class” to “Risk Category” to be consistent with ASCE 7 and the IBC.