involves photons of very tiny energy you're talking about electron volts as a unit for photon energy so when you're talking about a cup of v's then the photons are not energetic enough to ionize molecules very safe but we use x-ray photons that are so energetic thousands of v's they'll knock off electrons out of molecules do eyeliners tissue and cause problems such as DNA DNA damage and so the ionizing radiation parted of the EMR electromagnetic spectrum causes the problems right so we're working this region which is very safe more