This technical specification will provide guidelines to quantify and identify nanoscale particles of carbon black and amorphous silica in air samples collected in an industrial environment. The guidelines describe air sample collection and the characterization of the particles in the air samples by particle size and chemical identity. The particles in the air sample are collected in the various stages of a cascade impactor for particle size between 7 nm and 10 um. The number particle size distribution is measured on real time based on the particle aerodynamic diameter. Simultaneously, samples are collected for off-line analysis. The samples collected from each stage are characterized by Transmission Electron Microscopy (TEM) Energy Dispersive Spectroscopy (EDS).
The TEM -EDS measurement provides the chemical identity and source of the particles in each stage. Scanning Electron Microscopy (SEM) is also an option to TEM in the electron microscopy/dispersive spectroscopy combination. The concentration of particles of a specific nanomaterial in a given size range (#/cm3) is given by the product of the total particle count for size range (#/cm3) obtained from the cascade impactor and the fraction of particles identified as the specific nanomaterial of interest from the TEMEDS results.
The technique is limited to the measurement of particles in the size range of 7nm to 10 um, that can be observed by TEM/SEM and chemically characterized by EDS. The technical specification includes: (1) Scope, (2) Normative References, (3) Terms and Definitions, (4) Principle, (5) Symbols of units and abbreviations, (6) Reagents, (7) Apparatus, (8) Air Sample Collection, (9) Procedure for Analysis, (10) Test Report and (11) Bibliography.