Dr Alison S Geyh and colleagues at Johns Hopkins University evaluated the personal and microenvironmental aerosol speciation sampler (PMASS) prototype developed by Dr. Susanne Hering with HEI funding (HEI Research Report 114). The precision and accuracy of the prototype, which measures PM2.5 mass, elemental and organic carbon, sulfate, and nitrate, was evaluated in two locations with different PM composition. Baltimore, Maryland (outdoors), and Fresno, California (indoors). Geyh and colleagues set a target of 10% precision and 10% accuracy for all species measured.
