Method for operating a vacuum cleaning apparatus , in particular a vacuum cleaner, having a filter element , a filter element cleaning device , a control device , a turbine for sucking in an air stream (LS) through the filter element , a first pressure sensor and a second pressure sensor , wherein the first pressure sensor , for determining a first pressure value, is positioned upstream of the filter element in the flow direction (R), and the second pressure sensor , for determining a second pressure value, is positioned downstream of the filter element in the flow direction (R), wherein the method steps are: - operating the vacuum cleaning apparatus to suck in the air stream (LS) through the filter element , with the further characterizing method steps of: - determining a first pressure reference value according to the relationship of the first pressure value to the second pressure value; - measuring the pressure difference between the first and second pressure values; - dedusting the filter element by means of the filter element cleaning device if the value of the pressure difference between the first and second pressure values reaches a first predetermined threshold value; - determining a second pressure reference value according to the relationship of the first pressure value to the second pressure value, after the end of the dedusting of the filter element ; - determining a difference value between the second pressure reference value and the first pressure reference value; and - dedusting the filter element by means of the filter element cleaning device if the difference value between the second pressure reference value and the first pressure reference value reaches a second predetermined threshold value, or switching off the vacuum cleaning apparatus if the difference value between the second pressure reference value and the first pressure reference value reaches a third predetermined threshold value. - operating the vacuum cleaning apparatus to suck in the air stream (LS) through the filter element , with the further characterizing method steps of: - determining a first pressure reference value according to the relationship of the first pressure value to the second pressure value; - measuring the pressure difference between the first and second pressure values; - dedusting the filter element by means of the filter element cleaning device if the value of the pressure difference between the first and second pressure values reaches a first predetermined threshold value; - determining a second pressure reference value according to the relationship of the first pressure value to the second pressure value, after the end of the dedusting of the filter element ; - determining a difference value between the second pressure reference value and the first pressure reference value; and - dedusting the filter element by means of the filter element cleaning device if the difference value between the second pressure reference value and the first pressure reference value reaches a second predetermined threshold value, or switching off the vacuum cleaning apparatus if the difference value between the second pressure reference value and the first pressure reference value reaches a third predetermined threshold value. <EOS>