Irradiation can be used to sterilize all, EXCEPT:

Endoscopes that enter sterile tissue or a sterile body cavity (i.e., ahroscopes, laproscopes) must be subjected to a sterilization process before each use. This should be steam, ethylene oxide. If this is not feasible, the endoscopes must at least receive high level disinfection, which consists of a 12 - 20 minute soaking in glutaraldehyde). Endoscopes that will not enter into a sterile cavity and will not violate mucous membranes (i.e., endoscopes, bronchoscopes, cystoscopes) must at least receive a 20 minute soaking in glutaraldehyde, peracetic acid, or hydrogen peroxide before each use. Ionizing radiation carries far greater energy than UV light. It, too, causes direct damage to DNA and produces toxic free radicals and hydrogen peroxide from water within the microbial cells. Cathode rays and gamma rays from cobalt-60 are widely used in industrial processes, including the sterilization of many disposable surgical supplies such as gloves, plastic syringes, specimen containers, some foodstuffs, and the like, because they can be packaged before exposure to the penetrating radiation. Ref: Ray C.G., Ryan K.J. (2010). Chapter 3. Sterilization, Disinfection, and Infection Control. In C.G. Ray, K.J. Ryan (Eds), Sherris Medical Microbiology, 5e.