The Fukushima Event: The Outline and the Technological Background

Table 5

Fraction of radioactivity release from spent fuel pool to reactor building following “zirconium-fire” (NUREG 4982, 1987).

Fission product category	Fraction of initial inventory*	Notes
Noble gases	1.0
Halogens	1.0
Alkali Metals	1.0	Conservative value. Large uncertainty.
Tellurium	0.02	1.0 in the case of Sb.
Barium-Strontium	0.002
Noble Metals	2×10^−5	0.10 in the case of Co.
Lanthanides	1×10^−6	0.01 in the case of Nb.
Cerium	1×10^−6

* “Decontamination factor”.