Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.




David L. Duewer, Willie E. May, Reenie M. Parris, Michele M. Schantz, Stephen A. Wise


Abstract. Solutions of known mass fraction of organic analytes of interest are typically used to calibrate the measurement processes used in the determination of these analytes. Appropriate value assignments and uncertainty calculations for these calibration solutions are critical. For the Mutual Recognition Arrangement (MRA) developed by the CIPM, there are numerous Calibration and Measurement Capability Claims (CMCs) published in Category 3 Organic Solutions in the CIPM MRA Appendix C. Additional CMCs in this category are being proposed and reviewed. Evidence of successful participation in formal, relevant international comparisons is needed to support these claims. A CCQM pilot study conducted in 2004 was comprised of three parts: CCQM-P31a Organic Solution – Polycyclic Aromatic Hydrocarbons (PAHs), CCQM-P31b Organic Solution – Polychlorinated Biphenyl (PCB) Congeners, and CCQM-P31c Organic Solution – Chlorinated Pesticides. After review of the P31b results at the April 2004 OWG meeting and the October 2004 OAWG meeting (Beijing 2004), it was decided to proceed with a key comparison study for PCB congeners in solution (CCQM-K40) with a concurrent second pilot study for the PCB congeners in solution (CCQM-P31b.1). CCQM-K40 was designed as part of a suite of CCQM studies designed to enable evaluation of various uncertainty components of the measurement process for the determination of PCB congeners in marine tissue samples.


CCQM, key comparison, k40, PCB, congeners


Duewer, D. , May, W. , Parris, R. , Schantz, M. and Wise, S. (2005), CCQM –K40– DETERMINATION OF PCB CONGENERS IN SOLUTION: FINAL REPORT, BIPM, [online],, (Accessed April 22, 2024)
Created October 4, 2005, Updated September 25, 2020