 Therefore, a beta particle emitted from decaying fission products would need to have a velocity greater than 99.97% "c" in order to produce Cherenkov radiation.Because the energy of beta particles produced during nuclear decay do not exceed energies of about 20 MeV (20.6 MeV for 14B is likely the most energetic with 17.9 MeV for 23Na being the next highest energy beta emitter) and the energy needed for a beta particle to attain 99.97% c is 21.1 MeV formula_1, the possibility of Cherenkov radiation produced in air via a fission criticality or a radioactive decay is virtually eliminated.Cherenkov radiation can be however readily observed in more optically dense environments, "e.g."