Behavioral audiograms were taken on five surgically monaural chinchillas at 0.75, 1.5, 4.0, 6.0, 7.9, 11.0, 14.5, and 16.5 kHz. After exposure to 1 to 4 impulses of 168‐dB peak SPL and 60‐μsec A‐wave duration, temporary threshold shift was monitored at 1.5, 6.0, and 14.5 kHz for 32 days and complete audiograms taken at 64 days post‐exposure. Shifts were similar to those found by other researchers who have exposed the chinchilla to similar impulses, but were larger than those seen in monkeys and men exposed to the same impulse noise source. Cochlear hair cell losses for the five subjects exposed to one to four impulses were small and not significantly different from those of five others exposed to 10 to 40 impulses (but not tested behaviorally). The conclusions paralleled those of Hunter‐Duvar and Elliott [J. Acoust. Soc. Am. 52, 1181–1192 (1972)] in that stimulation “sufficient to produce permanent threshold shifts of 10–20 dB may not produce anatomical injuries to the organ of Corti that are detectable by phase microscopy.” Caution was urged in generalizing the results of impulse noise studies in chinchilla to human damage risk criteria. The use of pre‐exposure impedance measures to rull out middle ear conductive losses was also suggested for future studies.