DIESEL EXHAUST MINE DUST VIRTUAL IMPACTOR PERSONAL AEROSOL SAMPLER - DESIGN, CALIBRATION AND FIELD-EVALUATION

A virtual impactor personal aerosol sampler (VIPAS) has been developed for use in diesel-equipped mines to collect size-separated samples of diesel exhaust and mine dust particles in the respirable size range. This sampler consists of three stages: a 10-mm cyclone, a 0.8-mum cutp oint virtual impactor and two filter cassettes. The large nonrespirabl e particles are removed in a 10-mm cyclone. The respirable particles f rom the cyclone pass through a 0.8-mum cutpoint virtual impactor with the particles larger than and smaller than 0.8 mum (mine dust and dies el exhaust particles, respectively) collected on two 37-mm filter cass ettes. The sampling flow rate is 2 L/min so as to be compatible with t he standard respirable dust sampler and personal sampling pumps.