Sylmar Faraday Cage

The Sylmar Faraday Cage is comprised almost entirely of hot-dip galvanized steel. Constructed in 1969, this structure is covered by 400,000 ft2 (121,920 m2) of galvanized wire mesh. It is built to suppress emissions from heavy transformers that are capable of interfering with radio, telephone and television signals. The faraday cage encompasses over 2,000 tons (1,814 tonnes) of galvanized steel, with over 1,600 tons (1,451 tonnes) used to build the 65 ft. (20 m) support structure for the electromagnetic screen. Galvanized steel towers are also used in the switching equipment, which transmits over 1,600 megawatts of power daily. For the last 33 years, Sylmar Faraday Cage has remained completely maintenance-free. Although most of the galvanized surface has naturally weathered to a dull gray, some light spangle appearance is still intermittently visible on the structure. The coating thickness averages 6.84 mils , nearly double the ASTM minimum requirement for newly galvanized steel. Located in a moderately industrial environment, the galvanized coating should continue to provide maintenance-free corrosion prevention for an additional 40 years.