Hydrogen chloride and hydrogen bromide have been irradiated with single electron pulses at a very high intensity (1027 eV g−1 s−1) with a Febetron 705. At room temperature the yields of hydrogen from hydrogen chloride and hydrogen bromide, for pressures between 700 and 1200 Torr, are G(H2) = 8.1 ± 0.2 and G(H2) = 9.9 ± 0.3, respectively. These are the same as the yields observed at low dose rates. Detailed lifetime calculations, however, show that the mechanism is significantly different at the higher dose rate. Scavenger experiments with chlorine in hydrogen chloride show that the negative ion intermediates form thermal hydrogen atoms.The value of G(N2) = 12.4 ± 0.2 from nitrous oxide at a dose rate of 1027 eV g−1 s−1 is confirmed and the use of nitrous oxide as a dosimeter for pulsed electron beams is discussed. The higher nitrogen yield at Febetron dose rates appears to be due to changes in the reactions of electrons.