Tritium ordinary hydrogen, but they do fuse the small minority of deuterium nuclei. Like the other isotopes of hydrogen, tritium is difficult to confine. Rubber, plastic, and some kinds of steel are all somewhat permeable. This has raised concerns that if tritium were used in large quantities, in particular for fusion reactors, it may contribute to radioactive contamination, although its short half-life should prevent significant long-term accumulation in the atmosphere. The high levels of atmospheric nuclear weapons testing that took place prior to the enactment of the Partial Test Ban Treaty proved to be unexpectedly useful to oceanographers. The high levels
Isotopes of hydrogen u) is known as "tritium" and contains one proton and two neutrons in its nucleus. It is radioactive, decaying into helium-3 through β− decay with a half-life of 12.32 years. Trace amounts of tritium occur naturally because of the interaction of cosmic rays with atmospheric gases. Tritium has also been released during nuclear weapons tests. It is used in thermonuclear fusion weapons, as a tracer in isotope geochemistry, and specialized in self-powered lighting devices. The most common method of producing tritium is by bombarding a natural isotope of lithium, lithium-6, with neutrons in a nuclear reactor. Tritium was once used