Editing Fusion power (section)

=== Atmospheric tritium release ===
The natural product of the fusion reaction is a small amount of [[helium]], which is harmless to life. Hazardous tritium is difficult to retain completely.

Although tritium is volatile and biologically active, the health risk posed by a release is much lower than that of most radioactive contaminants, because of tritium's short half-life (12.32 years) and very low decay energy (~14.95&nbsp;keV), and because it does not [[bioaccumulation|bioaccumulate]] (it cycles out of the body as water, with a [[biological half-life]] of 7 to 14 days).<ref name="nuclearsafety-petrangeli">{{cite book|first=Gianni |last=Petrangeli|title=Nuclear Safety|url={{google books |plainurl=y |id=5X2Hxad9BoQC|page=430}} |date=2006|publisher=Butterworth-Heinemann|isbn=978-0750667234|page=430}}</ref> ITER incorporates total containment facilities for tritium.<ref name="ITER" />

Calculations suggest that about {{convert|1|kg}} of tritium and other radioactive gases in a typical power station would be present. The amount is small enough that it would dilute to legally acceptable limits by the time they reached the station's [[perimeter fence]].<ref name="WorldEnergyCouncil" />

The likelihood of small industrial accidents, including the local release of radioactivity and injury to staff, are estimated to be minor compared to fission. They would include accidental releases of lithium or tritium or mishandling of radioactive reactor components.<ref name="economic prospects" />