## Appendix M: Half-Lives for Several Radioactive Isotopes

Half-Lives for Several Radioactive Isotopes
Isotope Half-Life[1] Type of Emission[2] Isotope Half-Life[3] Type of Emission[4]
$_6^{14}\text{C}$ 5730 y $({\beta}-)$ $_{83}^{210}\text{Bi}$ 5.01 d $({\beta}-)$
$_7^{13}\text{N}$ 9.97 m $({\beta}+)$ $_{83}^{212}\text{Bi}$ 60.55 m $({\alpha}\;\text{or}\;{\beta}-)$
$_9^{15}\text{F}$ 4.1 × 10−22 s $(p)$ $_{84}^{210}\text{Po}$ 138.4 d $({\alpha})$
$_{11}^{24}\text{Na}$ 15.00 h $({\beta}-)$ $_{84}^{212}\text{Po}$ 3 × 10−7 s $({\alpha})$
$_{15}^{32}\text{P}$ 14.29 d $({\beta}-)$ $_{84}^{216}\text{Po}$ 0.15 s $({\alpha})$
$_{19}^{40}\text{K}$ 1.27 × 109 y $({\beta}\;\text{or}\;E.C.)$ $_{84}^{218}\text{Po}$ 3.05 m $({\alpha})$
$_{26}^{49}\text{Fe}$ 0.08 s $({\beta}+)$ $_{85}^{215}\text{At}$ 1.0 × 10−4 s $({\alpha})$
$_{26}^{60}\text{Fe}$ 2.6 × 106 y $({\beta}-)$ $_{85}^{218}\text{At}$ 1.6 s $({\alpha})$
$_{27}^{60}\text{Co}$ 5.27 y $({\beta}-)$ $_{86}^{220}\text{Rn}$ 55.6 s $({\alpha})$
$_{37}^{87}\text{Rb}$ 4.7 × 1010 y $({\beta}-)$ $_{86}^{222}\text{Rn}$ 3.82 d $({\alpha})$
$_{38}^{90}\text{Sr}$ 29 y $({\beta}-)$ $_{88}^{224}\text{Ra}$ 3.66 d $({\alpha})$
$_{49}^{115}\text{In}$ 5.1 × 1015 y $({\beta}-)$ $_{88}^{226}\text{Ra}$ 1600 y $({\alpha})$
$_{53}^{131}\text{I}$ 8.040 d $({\beta}-)$ $_{88}^{228}\text{Ra}$ 5.75 y $({\beta}-)$
$_{58}^{142}\text{Ce}$ 5 × 1015 y $({\alpha})$ $_{89}^{228}\text{Ac}$ 6.13 h $({\beta}-)$
$_{81}^{208}\text{Tl}$ 3.07 m $({\beta}-)$ $_{90}^{228}\text{Th}$ 1.913 y $({\alpha})$
$_{82}^{210}\text{Pb}$ 22.3 y $({\beta}-)$ $_{90}^{232}\text{Th}$ 1.4 × 1010 y $({\alpha})$
$_{82}^{212}\text{Pb}$ 10.6 h $({\beta}-)$ $_{90}^{233}\text{Th}$ 22 m $({\beta}-)$
$_{82}^{214}\text{Pb}$ 26.8 m $({\beta}-)$ $_{90}^{234}\text{Th}$ 24.10 d24.10 d $({\beta}-)$
$_{83}^{206}\text{Bi}$ 6.243 d $(E.C.)$ $_{91}^{233}\text{Pa}$ 27 d $({\beta}-)$
$_{92}^{233}\text{U}$ 1.59 × 105 y $({\alpha})$ $_{96}^{242}\text{Cm}$ 162.8 d $({\alpha})$
$_{92}^{234}\text{U}$ 2.45 × 105 y $({\alpha})$ $_{97}^{243}\text{Bk}$ 4.5 h $({\alpha}\;\text{or}\;E.C.)$
$_{92}^{235}\text{U}$ 7.03 × 108 y $({\alpha})$ $_{99}^{253}\text{Es}$ 20.47 d $({\alpha})$
$_{92}^{238}\text{U}$ 4.47 × 109 y $({\alpha})$ $_{100}^{254}\text{Fm}$ 3.24 h $({\alpha}\;\text{or}\;S.F.)$
$_{92}^{239}\text{U}$ 23.54 m $({\beta}-)$ $_{100}^{255}\text{Fm}$ 20.1 h $({\alpha})$
$_{93}^{239}\text{Np}$ 2.3 d $({\beta}-)$ $_{101}^{256}\text{Md}$ 76 m $({\alpha}\;\text{or}\;E.C.)$
$_{94}^{239}\text{Pu}$ 2.407 × 104 y $({\alpha})$ $_{102}^{254}\text{No}$ 55 s $({\alpha})$
$_{94}^{239}\text{Pu}$ 6.54 × 103 y $({\alpha})$ $_{103}^{257}\text{Lr}$ 0.65 s $({\alpha})$
$_{94}^{241}\text{Pu}$ 14.4 y $({\alpha}\;\text{or}\;{\beta}-)$ $_{105}^{260}\text{Ha}$ 1.5 s $({\alpha}\;\text{or}\;S.F.)$
$_{95}^{241}\text{Am}$ 432.2 y $({\alpha})$ $_{106}^{263}\text{Sg}$ 0.8 s $({\alpha}\;\text{or}\;S.F.)$

1. y = years, d = days, h = hours, m = minutes, s = seconds
2. E.C. = electron capture, S.F. = Spontaneous fission
3. y = years, d = days, h = hours, m = minutes, s = seconds
4. E.C. = electron capture, S.F. = Spontaneous fission