FIELD: physico-chemical methods for check-up, analysis and metrological support of gas analytical equipment, applicable for production of gas mixtures with concentration of dosed component varied in the process of device operation without any change of its operating conditions. SUBSTANCE: device is provided with a fluid resistor and an additional mixing chamber separated from the main partition conjugate to the gas-permeable surface of the microcurrent source and dividing it in a preset relation. According to the first modification, the device is provided with a three-position switching valve. According to the second modification, the device is provided with an apparatus allowing the microcurrent source to be moved relative to the device, or the device to be moved relative to the microcurrent source. The fluid resistor may be provided with an absorbent filter. The gas-permeable surface of the microcurrent source and the partition may be provided with conjugate position locks so as to simplify the installation of the microcurrent source in the 2-nd preset (certified) position. The device provides for variation of the quantity of contaminating gas used for preparation of gaseous mixture, without any change of the consumption and temperature conditions of operation of the device due to separation of the gas-permeable surface of the microcurrent source. EFFECT: reduced unproductive waste of time of device and microcurrent source operation at a transfer front one concentration to another one. 6 cl, 5 dwg
