Validation of the condensation particle counter UF-02M in laboratory and ambient conditions

Abstract

The main performance characteristics of the modernized condensation particle counter (CPC) UF-02M were determined. We studied the particle number concentration range of the instrument and the detection efficiency as a function of the particle diameter experimentally. In order to determine a cut-size D₅₀, the function was fitted to the experimental data. According to the fitting, the cut-size was 4.35 nm. The determined cut-size allows detecting the aerosol particles of the nucleation mode, giving possibilities to find many applications of the CPC UF-02M in the investigations of the aerosol nanometre particle dynamical properties. The counting efficiency of the CPC at high particle concentrations was experimentally investigated using silver particles of a 20  nm diameter. The minimum measured number concentration of aerosol particles was 0.003  cm^–3, the maximum was 150000 cm^-3 with the accuracy of 20%. The operation of the CPC UF-02M was compared with the operation of a commercially available SMPS TSI3936 under ambient conditions. The measured number concentrations were comparable with 5% accuracy. During the testing time, both instruments detected a new particle formation event. It was determined that the number concentration measured with the modernized CPC was higher than that determined by the SMPS. It was explained that a new CPC had a lower cut-size and detected smaller particles than the SMPS did.