The results from two field audits of Tenax-equipped sampling systems measuring the volatile organic (VOC) concentrations in ambient air are reported. The audited samplers collected the VOC's on Tenax GC (a solid adsorbent) with the VOC's later thermally desorbed and then analyzed by gas chromatography/mass spectrometry/computer (GC/MS/COMP). Each audit standard, prepared and certified by the National Bureau of Standards (NBS), contained at least four of the following compounds at the low parts per billion (ppb) level in dry N2: C6H6, C6H5CH3, C6H5Br, C6H5C1, CHC13, CC14 and C2C14. The results of the two audits were consistent and highlight some of the errors associated with sampling for VOC using Tenax GC. The agreement between successive sampling runs (repeatability) shows that the audit system itself is a viable means to audit the performance of VOC sampling systems at field sites.