ANNULAR ASPIRATION SLOT ENTRY EFFICIENCY OF THE CIP-10 AEROSOL SAMPLER

The CIP-10 personal or static aerosol sampler is designed to sample th e respirable, thoracic or inhalable aerosol fraction by using the appr opriate selector, All these versions have the same downward-oriented a nnular aspiration slot, The annular slot entry efficiency at a flow ra te of 10 I min(-1) was studied as a static sampler in an experimental wind tunnel, at first for a 1 m s(-1) wind velocity, Glass beads were generated as a test aerosol by a fluidized bed aerosol generator, A sh arp-edged thin-walled isokinetic probe was used for reference sampling , The particle size-dependent efficiency was deduced from the particle size distributions of both reference and annular slot samples, Partic le size distributions were measured as functions of the volume equival ent diameter D-v by the Coulter Multisizer technique, The aerodynamic particle diameter D-ae was deduced from D-v by using particle density and Reynolds number, The entry efficiency of the CIP-10 annular aspira tion slot at 1 m s(-1) is between 0.9 and 0.4 for the whole range of p article aerodynamic diameters within the range 10-60 mu m. By minimizi ng the inner particle deposit under the protecting cup of the selector , the instrument can meet the CEN sampling criteria for sampling of in halable aerosol as shown on the bias an accuracy maps.