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-μm cutpoint virtual impactor and two filter cassettes. The large nonrespirable particles are removed in a 10-mm cyclone. The respirable particles from the cyclone pass through a 0.8-μm cutpoint virtual impactor with the particles larger than and smaller than 0.8 μm (mine dust and diesel exhaust particles, respectively) collected on two 37-mm filter cassettes. The sampling flow rate is 2 L/min so as to be compatible with the standard respirable dust sampler and personal sampling pumps.