Recent claims of net energy production by “cold fusion” have prompted an examination of all the positive Q value, two-body nuclear reactions that might result from the fusion of any of the isotopes in the apparatus used by Fleischmann and Pons. Any energy production that may result from cold fusion would be accompanied by copious production of nuclear reaction products (on the order of 1013/s). Furthermore, the elementary properties of the alpha particle at the deuteron + deuteron threshold are discussed. An important property of the alpha at this high excitation is its nearly prompt (10−20 s) decay by particle emission to 3He + n or triton + proton.