Operating procedures, SEMS Section

Typically, colloidal suspensions are deposited on polycarbonate filters immediately following sampling to reduce post-collection precipitation or aggregation artifacts and mimic the operational procedures used to define dissolved and particulate sample components. Obviously, a well-dispersed dilute sample should be used to avoid artifactual particle overlap. Filter sections are then mounted on SEM stubs and carbon or metal coated (Au/Pd) for compositional analysis and micrographic imaging, respectively. The tedious nature of operator controlled analysis of particulate samples in the SEM and the TEM has often precluded the acquisition of statistically valid information regarding suspension composition. 

The central section of Figure 19.3 shows the SEMS rule. One of its sections is paragraph 250.1913 (e)(1) which is entitled Review of and changes to the procedures must be documented and communicated to responsible personnel. On the left of Figure 19.3 is the operator s SMS. His standards to do with changes to operating procedures are under Sections abc and xyz. On the... 

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