Did you know existing standards for broadcast and communications towers have been updated with their biggest revisions, some say, since their inception in 1949? The new standards have been in the works for six years. The standards committee, made up of members from TIA and EIA, is labeled "TR-14.7." The final version has was approved 10/20/04 at a meeting held in Denver and went back though for public response/comments 12/16/04. Public comments/balloting were completed 7/1. No major changes were made to the standard based on comments. So the TIA/EIA 222-G Standard will be published/printed this summer and officially take effect 1/1/06.

The last major revision of standard 222 was revision D in the late 80s. The G revision of the ANSI/TIA/EIA standard "Structural Standards for Steel Antenna Towers and Antenna Supporting Structures" changes the loads and design criteria for communication towers including broadcast structures. It will also have an impact on the load carrying capacity of existing structures.

For sheer volume of information, the 222-G standard outstrips its predecessors by three or four times, including more than 150 pages devoted solely to state-by-state map graphics illustrating wind, ice, frost and seismic factors. The large amount of material contained in this version will require electronic versions to also be made available. All new tower construction and major renovations of existing structures must conform to 222-G after its January 1st adoption. Existing towers will not be affected unless physical alterations are made or antenna loading exceeds the original, approved design. Which standard applies is usually a decision of the engineer of record.

"The standard says that anytime you add or move anything from a structure, you are required to do a structural analysis and will have to meet the new standard. As long as you don't change any of your loading, you're not required to reanalyze your towers. Other things that will change is you are now required to have a 10 ohm ground, which is something most broadcast structures already meet with no problem," says Sterling Smith, Director of Business Development, OTL (tower lighting).