The maximum dimensions for your carry-on bag are: Length - 24 (61cm) including wheels and handles ; Width - 17 (43cm) Height - 10 (25cm) For additional carry-on items beyond the one-bag limit, each piece will incur a fee. Refer to the checked baggage page for more information.
Tritium (3H) is the most stable radioisotope of hydrogen. That is, of all radioactive isotopes of hydrogen, tritium is the least radioactive. It has a proton and 2 neutrons in its nucleus. Tritium decays through beta minus decay and changes to helium-3. It has a half-life of 12.32 years.
Cs-135 has a half-life of 2.3 million years and emits beta particles with an energy of 267 keV. Cs-137 has a half-life of 30 years and emits beta particles with an energy of 605000 keV. If you stood next to a million atoms of Cs-137 for a year 22840 atoms would decay, for a total energy release of 2.2 nanojoules.