The influence of the operating mode of arrays of gated vacuum field emitters on the intrinsic failure rate of emitter tips has been investigated. In particular, the failure rates of arrays of gated silicon vacuum field emitters operating in a & and pulsed bias mode as a function of pulse duty cycle, pulse frequency, emitted current, and neutral gas pressure have been measured. There is a large reduction of the failure rate, per unit time that the array is emitting current, when emitters are operated in pulsed mode as compared to a & mode of operation. This reduction in the failure rate is dependent on the duty cycle of the pulses that the array is operated at but is independent of the repetition frequency of the pulses. The failure rate is an exponential function of the emitted current, both for the dc bias and for the pulse bias case. The increase in failures with increasing current is more rapid for a dc bias than for a pulse bias. The failure rate of gated vacuum field emitters increases rapidly with the neutral gas pressure, with the rate of increase in failures identical for a dc and a pulsed bias.