Complex sentence: Typically this occurs at doses of 15-20 Gray, far higher than any diagnostic scan and more typical of levels seen radiotherapy or deployment of nuclear armament, as seen in Hiroshima and Nagasaki during World War II with the atomic bomb attacks from the United States.
Split into simpler sentences: Typically this occurs at doses of 15-20 Gray, far higher than any diagnostic scan and more typical of levels seen radiotherapy or deployment of nuclear armament. Historically, this was a common phenomenon in Hiroshima and Nagasaki during World War II with the atomic bomb attacks from the United States.