Charge generation and hole transport were measured in reoxidized nitrided oxide (RNO) and radiation-hard thermal oxide (OX) as a function of temperature from 77 to 295 K and applied field from 1 to 5 MV/cm using pulsed irradiation and a fast time-resolved current-voltage (I-V) measurement technique. The insulators show near-equal charge generation at 77 K and qualitatively similar dispersive hole transport with markedly different and strongly field-dependent activation energies. High-field acceleration of hole transport may be a useful radiation-hardening technique for low-temperature operation; RNO has advantages over OX for application of this technique.