|Examples of average beta energies|
Since the energy of beta electrons emitted by a radionucleide. is not unique, one compares generally radionucleides by their average beta energies. These energies vary considerably : for instance, the average energy of beta emitted by tritium is a hundred times lower than that of phosphorus-32.beta. The average energies are below 1 MeV, much lower than those of alpha particles (usually above 4 MeV).