The Steven E. Johnson High School was built in 1979 and first started off with Edwards 792 horn/strobes with an Edwards system.
In 1987, the alarms in the nurses office and the academic computer lab broke down and were replaced with Space Age Electronic 2DCD horns on AV34 strobe plates.
In 1991, choral, art and the hallway which lead to the media center had horns break down so they were replaced with Simplex 2901-9838s on Simplex 4903-9101 strobe plates.
In 1996, the school switched to Simplex and got a Simplex systems. All 792s except the ones in the health room, the business room and the library had their horns replaced with Simplex 4901-9805s on Simplex 4903-9105 strobe plates.
In 2002, the gymnasium was redone and the horns down there were replaced with Wheelock MT-24-LSM.
Three years later, the auditorium was also redone and the horns were replaced with Classic SpectrAlerts.