Within the frame of the requirements set out by the Packaging Directive 62/94, this paper recommends a method for the determination of mercury by cold vapour atomic absorption spectrometry (CVAAS). The study consisted of two parts: (i) a recovery study; (ii) a collaborative intercomparison carried out on an experimental glass incorporating Hg in traces. During the recovery study, the decomposition solution of a Hg free container was spiked with known amounts of Hg which were fully recovered by CVAAS. No significant interferences were found from other hydride forming elements. An intercomparison among ten laboratories carried out on a glass incorporating Hg traces showed an acceptable reproducibility at a mean concentration level of 1.10mg/kg.