A leak-testing method for a test container comprises measuring background noise within a chamber at atmospheric pressure with a trace sensor of volatile organic compounds that exhibit a measurement sensitivity less than or on the order of 1 ppb. Pollution is removed from an internal atmosphere of the chamber when the measurement of the background noise is greater than a predetermined threshold. The internal atmosphere of the chamber is mixed to homogenize a composition of the internal atmosphere receiving a container that defines a bounded internal space within which a volatile organic compound is present.A concentration of volatile organic compounds is measured within the atmospheric pressure chamber with the trace sensor of the volatile organic compounds. The measurement of the background noise is compared to the measurement of the concentration of the volatile organic compounds to detect the leak in the test container.