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Analysis Techniques

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Several techniques are used to assess the degree and nature of contaminating particles as collected on filters. If you are following a regulated method, this method may dictate the analysis technique. Refer to the online guide to Regulated Analytical Methods.

Ultimately, you will choose a technique based on any of several factors:
  • Size of contaminating particles
  • Heterogeneity of particle population
  • Number of samples/throughput needs
  • Skill/experience level of the analyst
  • Need to determine source of contamination
Follow these links for technical information on these methods:
  • Microscope-Based Techniques
    Microscope-based techniques, including optical microscopy and scanning electron microscopy, are best for determining the size distribution and nature of contaminating particles and the source of contamination.
  • Particle Identification
    This section provides a high-level overview of particle characteristics commonly used to identify contaminants by microscopy and other methods.
  • Colorimetric Patch Method
    Colorimetric methods are widely used for monitoring hydraulic fluids and aviation fuels.
  • Particle Gravimetric Analysis
    This section describes how to select filters, prepare samples, and calculate results of gravimetric analysis, one the most widely used methods for air and liquid monitoring.