A systematic comparison of thermal and epithermal irradiations in the instrumental activation analysis of coal and fly ash
was made. From a total of 44 elements, the epithermal irradiation technique appeared advantageous in 20 cases, namely Ni,
Ga, As, Se, Br, Rb, Sr, Zr, Mo, In, Sb, Cs, Ba, Sm, Ho, Hf, Ta, W, Th and U. Data are presented for the National Bureau of
Standards’ coal (SRM 1632) and fly ash (SRM 1633).