Sampling for Chemical Analysis

Sampling for Chemical Analysis
Facilitated by: Edgar F. Paski, Ph.D.

April 26, 2013 8:30 AM – 4:30 PM
Venue: Social Hall, PNP, EDSA cor. Bonny Serrano

Workshop objectives

To give participants an understanding of the critical influence of sampling on the quality of analytical results, especially for geological, environmental, and agricultural materials. Participants will gain familiarity with the principal topics covered in the Eurachem / CITAC Guide: Measurement Uncertainty Arising from Sampling (2007).

What you will learn

  1. You will learn the accepted terminology for the various types of sample materials present in the testing laboratory. 
  2. You will become familiar with the heterogeneity of solid objects.
  3. You will gain an understanding of measurement uncertainty and the importance of sampling as a component of measurement uncertainty.
  4. You will gain an understanding of the fundamental causes of sampling errors and learn how to estimate laboratory and field sampling uncertainties.

Who should attend

This workshop is designed for individuals engaged in the mining and minerals processing, environmental monitoring, agricultural and food processing. The topics covered are relevant to geologists, agrologists, laboratory personnel, process engineers, managers, quality assurance and quality control specialists as well as supervisory personnel. 



Preregistration (On or before April 22)

On site

ICP Members

PHP 1,500.00 PHP 2,000.00
  Industry PHP 2,000.00 PHP 2,500.00

Non-ICP Members

PHP 2,000.00 PHP 2,500.00
  Industry PHP 2,500.00 PHP 3,000.00

Registration may be made on-line by email or through the ICP website. Please remit payment through the Bank of the Philippine Islands, Loyola Katipunan Branch. Name of Account: Integrated Chemists of the Philippines; Current Account Number: 3081-0830-95. Email or fax payment slip to the ICP office to guarantee reservation.

Workshop content:


Sampling and Variability in Solid Objects, Terminology


Uncertainty and Sampling Error

  • What is measurement uncertainty
  • Uncertainty propagation in chemical analysis
  • The Seven Sampling Errors according to Pierre Gy
The Model:

Pierre Gy’s Sampling Model

  • The Horowitz Curve
  • Pierre Gy’s Sampling Equation
  • Estimating Subsampling Variance

The Material:

Heterogeneity and Sampling Solid Substances

  • The Behavior of Granular Solids
  • Spontaneous Segregation in Granular Solids
  • Consequences for Splitting and Blending of Granular Solids
The Tools:

Tools and Techniques for Sampling

  • Devices for Sampling in the Analytical Laboratory
  • Sample Handling and Storage
The Techniques:

Practical Sampling of Solid Materials

  • Sample division and compositing
  • Preparing the laboratory sample
  • Extracting the test portion
The Results:

Sampling Uncertainty

  • Estimating sampling uncertainty in assay laboratories
  • Estimating field sampling uncertainty
  • Nugget effect

Practical experiments on subsampling granular materials, e.g.:

  • Cone & quarter
  • One dimensional line slice
  • Grab sampling
  • Riffle sampling

About the Facilitator

Ed Paski earned his B.Sc. in Chemistry at the University of Waterloo and his Ph.D. in Analytical Chemistry at the University of British Columbia. Dr. Paski has worked in industry and government in the areas of mining and mineral exploration, environmental chemistry, pulp and paper technology, agrology. He teaches courses in analytical atomic spectrometry, quality assurance and the assayer certification program at the British Columbia Institute of Technology (BCIT). He assesses testing laboratories to the ISO 17025 Standard for the Standards Council of Canada (SCC) and the Canadian Association for Laboratory Accreditation (CALA). Dr. Paski’s professional interests include: plasma spectrochemistry, sampling for chemical analysis, chemometrics, automated chemical analysis, trace elements in geological and environmental materials, quality assurance, laser applications in analytical chemistry, multidimensional luminescence spectrometry, computer applications in analytical chemistry, assaying precious metals.