Departmental Papers (EES)

Document Type

Journal Article

Date of this Version

October 2003


The photoacoustic effect may be exploited for the detection and localization of gas leaks from otherwise sealed components. The technique involves filling the test component with a tracer gas, and radiating the component to produce photoacoustic sound from any leak site where tracer gas is present. This paper describes demonstration experiments utilizing 10.6-µ radiation from a carbon-dioxide laser and sulfur hexafluoride as a tracer gas for photoacoustic leak testing at leak rates between 6×10–5 cm3/s (1 cm3 in 4.6 h) and 5×10–9 cm3/s (1 cm3 in 6.3 years). The technique may reach or exceed the capabilities of the most sensitive commercial leak test systems using helium mass-spectrometers. In addition, comparison of the measured results to a simple scaling law suggests that tracer gas cloud geometry influences the photoacoustic signal amplitude.


Copyright ASA. Reprinted from Journal of the Acoustical Society of America, Volume 114, Issue 4, October 2003, pages 1926-1933 .
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Date Posted: 27 July 2005

This document has been peer reviewed.