Application of the Scanning Electron Microscope/X-Ray Spectrometer to Automobile Exhaust Particulates

The advantages of using the scanning electron microscope (SEM) to characterize automotive particles are described. The sample, collected using an Andersen sampler, is bombarded with electrons and the resultant x-rays are analyzed with an energy dispersive spectrometer.

After many particles were observed, classifications were made for individual particles of one structural type greater than 3 μ in size; agglomerates, single masses of particles less than 1 μ; fines, particles of 500-1000 Å; and atypical particles.

It is felt that with the advances in methods and technology this procedure will provide a strong basis for future sampling characterization and identification.