A new version of isotope dust concentration gauge for monitoring airborne dust pollution of the air employs a ready made personal computer as the control and processing unit in the gauge instead of specialized electronics. That solution of the gauge reduces the needed specialized electronics to a simple computer interface coupling the computer to the measuring head. This also reduces electronics of the measuring head itself, i.e. GM detector circuit, power supplies and electronic circuits to switch on/off driving motors. The functioning and operation of the gauge is controlled by the computer program that can be easily modified if needed. The computer program for the gauge enables automatic measurements of dust concentration. Up to fifty measuring cycles can be easily programmed for a day. The results of measurements are presented in the form of data collection, diagram of dust concentration distribution during one day, diagram of dust distribution during 30 successive days or diagram of average dust concentration distribution during a day which may be computed by combining data of the selected number of measurements. Recalibration of the gauge and checking up of the gauge are also carried out under the program control. Functioning of the gauge is illustrated in nine drawings and diagrams.