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The photoacoustic effect may be exploited for detection and localization of gas leaks on the surface of otherwise sealed components. The technique involves filling the test component with a photoactive tracer gas, and irradiating the component to produce photoacoustic sound from any leak site where a tracer gas cloud forms. This presentation describes demonstration experiments utilizing 10.6‐μm radiation from a nominally 145‐W carbon‐dioxide laser with sulfur hexafluoride as a tracer gas. Here, photoacoustic sounds from six NIST‐traceable calibrated leak sources with leak rates between 1 cc in 4.6 h, and 1 cc in 6.3 years were recorded with 12 microphones in a bandwidth from 3 to 80 kHz. Bartlett matched‐field processing of the microphone array measurements both detect and localize these leaks when the leak and the array are separated by 152 mm. These experiments suggest that the sensitivity of photoacoustic leak testing may reach or even exceed the capabilities of the most sensitive commercial leak test systems using helium mass‐spectrometers. Comparison of the measured results and an analytical scaling law suggests that tracer cloud geometry influences the photoacoustic signal amplitude. [Work supported by the U.S. Dept. of Energy.]