I remind my readers that only a handful of the more than 15 000 accelerators in operation around the world are used in particle-physics research. This fact would not surprise Ernest O. Lawrence, who saw an importance far beyond physics research. He and his brother John, a physician, pioneered the medical applications of accelerators at Berkeley. Today, one-third of all accelerators are involved in medical applications, such as cancer therapy, imaging, and the production of short-lived isotopes. The other two-thirds are used for industrial applications ranging from micro-machining to food sterilization and for national security applications, which include x-ray inspection of cargo containers and nuclear stockpile stewardship.
This data clearly show why the field of accelerator physics transcends beyond just what they are normally perceived as, which is particle-physics/colliders. This is a good article to read if you're bored.