History of System Safety

The concept of system safety was first introduced in the 1940s. However, prior to that, safety was generally achieved by attempting to eliminate hazards in the initial design and then correcting other problems as they appeared after a product was in use or at least in a testing phase. In other words, a trial and error methodology was utilized. In aviation, this became known as the "fly-fix-fly" approach. An aircraft would be designed using the best knowledge available, flown until it crashed, then fixed and flown again. These approaches were not adequate for systems that had to be first-time safe. Thus began the concept of system safety and its evolution. The engineering and safety communities developed the concept in order to design and build safer equipment by applying lessons learned from accident investigations. In response to the dissatisfaction with the "fly-fix-fly" approach, the following decades saw many new developments in the system safety concept.