Commonly Used Nuclear Energy Units and Abbreviations Prefixes and Numerical Values Basic Unit Measured Pico. Property 10 barn cross section curte radioactivity dose rate radiation dose electron volt energy gram mass meter length rad (radiation absorbed dose) radiation roentgen wuCi; wpe Mero mre 10 10 Ki ° Mega 1 1 10 kChs MCi ke MeV yb mb b uHCi; mCi; Ci; uc mc mR/hr; mr/hr c r/hr, rem/hr mg g kg km mm m urad mrad rad dose ur uR; mR; Rs r rem (roentgen equivalent man) radiation dose prem mrem rem rep (roentgen equivalent physical) radiation dose urep mrep rep second time us ms Ss ton (TNT device energy watt power equivalent) radiation ug LWW pW mr mw Mc R/hr; eV uUg ke W KT MT kw Mw 489 AFP