of the truck mounted concrete pump 10 are defined by the position of the support legs 34 in order for the machine to stand securely the center of gravity must always be located within the tipping limits 36 as is shown for a possible center of gravity line 38 during a 360 u00b0 rotation of the concrete distributing boom 14 accordingly static stability is put at risk when vehicle inclination is outside an inclination range of for example not more than 3 u00b0 in addition the support legs 34 and the slewing gear 32 can be overstressed by the direction dependent loadings which occur with an inclined position of the vehicle fig1 shows the case in which the terrain 40 at the work location has a terrain inclination 42 with respect to the horizontal 44 such that the vertical axis 30 deviates in operation from the axis of gravity 46 normal to the horizontal by an angle u03b2 of for example 5 u00b0 in this case the operating range 48 of the concrete distributing boom 14 is restricted appropriately by the electronic safety device 20 in order to ensure the required static stability and to avoid overloadings this is achieved by limiting the rotary motion at the slewing gear 32 and or the swiveling movement of at least one boom arm as a function of the inclination of the truck mounted concrete pump 10 this inclination is suitably detected three dimensionally and in a direction dependent manner by means of the tilt sensor 18 mounted on the vehicle so that not only the absolute inclination angle u03b2 but also the horizontal angle of the largest inclination.