HISTORY OF THE TOWER STANDARD

• 1959 — EIA RS-222 (Revision of TR-116 and RS-194) - The country's first standard for antenna supporting structures and antennas is published. The 11-page standard delineates the nation into three wind uniform pressure zones: A, B and C. The wind loading was considered over the full length of the structure and was measured in pounds per square foot (PSF). The standard explained that "Ice coatings are not specifically stated as icing seldom occurs simultaneously with maximum wind loading."
• 1966 – EIA RS-222-A
• 1972 – EIA RS-222-B
• 1976 – EIA RS-222-C
• 1987 – EIA 222-D Wind pressures are replaced by basic wind speeds (mph). A new wind velocity map is introduced. The value for basic wind speed increased as a function of tower height above 33 feet AGL.
• 1991 – TIA/EIA 222-E The first iteration of the code to be defined by the TIA and Electronics Industries Association (EIA).
• 1996 – TIA/EIA 222-F This standard was used during the country's greatest build out of towers and is currently the most adopted standard in the nation. Expanded the scope of the previous version to include the effects of ice loading. Basically, it provided two methods for analysis of ice.
• 2006 – TIA-222-G With the standard's most sweeping changes, Revision G has been adopted by some states and local jurisdictions. The analysis of tower structures is now consistent with other structures. Design philosophy changed to limit states design from allowable stress design. With recognition from the International Building Code, most states and municipalities will eventually adopt the revision.