background radiation

level of ionizing radiation present in the natural environment

en-US/ˈbækˌɡɹaʊnd ˌɹeɪdiˈeɪʃən/
en-GB/ˈbækɡɹaʊnd ˌɹeɪdɪˈeɪʃən/

دسته بندی ها:

ionizing radiation