VDI 3867 Blatt 6:2012-12 (R2018)

This guideline specifies a method for determining the particle number concentration and number size distribution in ambient air with an Electrical Low Pressure Impactor (ELPI). The measurements are performed in real time. The guideline deals with the principles of the method and explains the calibration, use and maintenance of the measuring instrument. This method is also suitable for characterising test aerosols. The method is applicable for particles in the size range of about 7 nm to about 10 µm and in the number concentration range of about 200 cm-3 to about 2x107 cm-3.