In the best of all worlds a desirable property of an enzyme that confers radiation protection would be that it itself would be relatively insensitive to radiation. Such insensitivity was suggested by experiments on SOD carried out by researchers at another of AECL’s Labs (Whiteshell) located near Winnipeg, Manitoba. The researchers involved there were a medical doctor, Abe Petkau, and a biochemist, W.S. Chelack. As chance would have it I met Dr. Petkau at a meeting of the American Biophysical Society. After looking over the results he was presenting, I suggested that small angle scattering could help to elucidate the theory he and Chelack were advancing for SOD’s effectiveness as a protective enzyme against negatively charged oxygen molecules.