A new method of Differential Mobility Analyzer (DMA) operation using a Fast Scanning Differential Mobility Analyzer (FDMA) nanometer particle sizer has been implemented. By optimizing the flow and voltage ramps, improvements can be made in the FDMA's measurement size range, counting statistics and resolution. In this study, an electrostatic classifier was used to generate mono-dispersed particles of different sizes to calibrate the delay time of the FDMA. The aerosol from incense combustion could be measured directly by FDMA although the particulate concentration was as high as 1,011 particles cm-3. The resolution of the FDMA was 3 nm and better than the SMPS (10nm).