This analytical method is a validated measurement procedure for the determination of 2-butanone oxime [96-29-7], acetone oxime [127-06-0], 4-methyl-2-pentanone oxime [105-44-2] and 2-pentanone oxime [623-40-5] after personal or stationary sampling. Sampling is performed by drawing a defined volume of air through sampling tube filled with Chromosorb 106 using a suitable flow-regulated pump. After liquid desorption with methanol, the ketoximes retained on the adsorbens are analysed using gas chromatography with nitrogen-selective detection. The relative limits of quantification (LOQs) are between 0.04 and 0.05 mg ketoxime/m³ for an air sample volume of 40 l. The mean recoveries for the ketoximes were between 84 and 93%. The concentration-dependent expanded uncertainty was 17% to 23%. This analytical method has been accredited by the accident insurance companies for the detection in workplace air of substances that are carcinogenic, mutagenic or toxic to reproduction. This method has been tested and recommended for the determination of 2-butanone oxime, acetone oxime, 4-methyl-2-pentanone oxime and 2-pentanone oxime in work areas by the German Social Accident Insurance (DGUV). Both personal and stationary sampling can be performed for measurements in order to evaluate work areas.