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Appendix B

Gas chromatograph calibration sensitivity for PFT analysis

  1. Perform the procedures for standard dilutions, injections, and peak integrations as described in Appendix A. Record the injection volume, dilution used, and peak area for each standard from a given site, organized by date of sample analysis.
  2. For each site, plot the log of the PFT(g) contained in each injection against the log of the standard’s integrated peak area (log[PFT injected] vs. log[peak area]). If necessary, discriminate between standards run on different dates by plotting them as separate series.
  3. For each separate date of standard analysis (each series), add a linear trend line and display all corresponding equations.
  4. From the trend line equations of the following format, record each series’ m and b values:
  5. y = mx + b,


    • y = log of peak area,
    • x = log of mass injected,
    • b = intercept derived from the calibration curve, and
    • m = slope derived from the calibration curve.
  6. Average the m and b values for each site. This implies that peak area = 10b (PFT mass injected)m.
  7. Use the average m and b values from each site to form the final calibration trend line (insert them into the generalized linear equation of y = mx + b).