triitium

Tritium is a radioactive isotope of hydrogen. Its nucleus contains one proton and two neutrons, giving it an atomic mass of three. This makes it a heavier form of hydrogen, often referred to as "heavy hydrogen" or "super-heavy hydrogen." Tritium is naturally produced in the Earth's upper atmosphere by the interaction of cosmic rays with atmospheric gases. It is also produced industrially for various applications.

The most common form of tritium is tritium gas, denoted as T2 or H-3. Tritium decays by emitting a beta particle and transforming into helium-3. Its half-life is approximately 12.3 years. Due to its radioactivity, tritium must be handled with care. It is a low-energy beta emitter, meaning its radiation is relatively weak and can be stopped by a thin layer of material, such as skin. However, if ingested or inhaled, it can pose a health risk.

Tritium has several important applications. It is widely used in self-powered lighting devices, such as exit signs and watch dials, where it provides a continuous, maintenance-free light source. It is also utilized in scientific research, particularly in biological and chemical tracing experiments. In nuclear fusion research, tritium is a key fuel component. Due to its radioactive nature and potential for misuse, the production, possession, and transfer of tritium are subject to strict regulations in most countries.