Shock Response Spectrum (SRS) analysis was under development as a standard data processing method in the early 1960’s.  SRS was initially used by U.S. Department of Defense engineering contractors and government R&D facilities.  Dr. Irwin Vigness of the U.S. Navy Research Lab did much to establish the method as an indicator of mechanical shock severity.

There is not quite the same motivation to apply the method today, because modern computer and signal processing technology makes it possible to directly compute the response of specific structures resulting from well-defined actual transient forces.  Nevertheless, the SRS analysis method continues to grow in popularity with vibration test labs and analytical organizations.  

The method is even gaining in popularity for steady state vibration applications as well as transients.  NASA routinely applies the method for evaluating the severity of Orbiter Payload Bay vibration to new payloads.

Read the white paper here.