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An Inverse Analysis Approach to the Characterization of Chemical Transport in Paints
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Error bounds in diffusive sampling with reversible adsorption.

D W Underhill1

  • 1Department of Environmental Health Sciences, School of Public Health, University of South Carolina, Columbia, SC 29208, USA.

Talanta
|February 1, 1993
PubMed
Summary
This summary is machine-generated.

Diffusive samplers require careful calibration for workplace gas monitoring. This study defines a permissible sampling time to minimize errors caused by fluctuating analyte concentrations, ensuring accurate time-weighted average (TWA) measurements.

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Area of Science:

  • Occupational health and safety
  • Environmental monitoring
  • Analytical chemistry

Background:

  • Diffusive samplers are widely used for workplace air quality assessment.
  • Standard calibration methods may introduce errors due to variable workplace concentrations.
  • Accurate time-weighted average (TWA) concentration monitoring is crucial for regulatory compliance.

Purpose of the Study:

  • To address the inaccuracies in diffusive sampler calibration under non-constant workplace concentrations.
  • To develop a method for determining a permissible sampling time that accounts for concentration fluctuations.
  • To ensure reliable TWA concentration measurements regardless of analyte variability.

Main Methods:

  • Analysis of maximum possible error in TWA concentration calculations.
  • Development of a permissible sampling time definition.
  • Consideration of unrestricted concentration functions over time.

Main Results:

  • A method to define a permissible sampling time was established.
  • This permissible sampling time minimizes calibration errors.
  • The approach is valid for any concentration fluctuation pattern.

Conclusions:

  • The defined permissible sampling time enhances the accuracy of diffusive samplers.
  • This method improves compliance monitoring for gases and vapors in dynamic workplace environments.
  • Accurate TWA measurements can be achieved even with fluctuating analyte levels.