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.

CCQM Activities in the Inorganic Analysis Working Group and the Electrochemical Analysis Working Group


NIST maintains an active role in these two CCQM working groups, participating in international key comparisons and pilot studies, organizing new studies, and working with other national metrology institutes to improve the efficiency and effectiveness of CCQM studies.


World map with five country groups highlighted in different colors.
Credit: Victor Korniyenko

Together with other NMIs participating in the Inorganic and Electrochemical Analysis Working Groups (IAWG and EAWG) the work is intended to provide an open, transparent and comprehensive scheme to give users reliable quantitative information on the comparability of national metrology services and to provide the technical basis for wider agreements negotiated for international trade, commerce and regulatory affairs as set forth under the CIPM Mutual Recognition Arrangement (MRA).

Major Accomplishments

NIST participated in several IAWG and EAWG studies during the past three years including:

  • CCQM-K58 Silicon Nitride      
  • CCQM-P100.1 and P100.2 Mercury in Pure Water      
  • CCQM-K49 and P85 Elements in Bovine Liver, organized by NIST      
  • CCQM-K73 and P19.2 Amount Content of H+ in 0.1 mol·kg-1 Hydrochloric Acid
  • CCQM-K75 Platinum and Nickel in Algae
  • CCQM-P106 Cd, Cr, Hg, and Pb in Polypropylene     
  • CCQM-P107 Purity of Zinc
  • CCQM-P119 Determination of Lead in Lead-Free Solder Containing Silver and Copper
  • CCQM-K20 Tetroxalate pH Buffer
  • CCQM-K43.1 Methylmercury in Marine Fish      
  • CCQM-K48 Assay of Potassium Chloride
  • CCQM-K56 Trace Elements in Soybean Flour
  • CCQM-P96 Arsenic and Arsenobetaine Content in Marine Fish     
  • CCQM-P97 Cadmium and Lead in Herbs

Additional Technical Details

Decisions to participate in Key Comparisons and Pilot studies organized by the IAWG and EAWG are based on existing or planned CMCs that are maintained by NIST in these measurement areas. Measurements are performed using the identical methods and instrumentation that are used by NIST to certify Standard Reference Materials for inorganic and electrochemical measurands.

Associated Publications

1. Liandi, M. A., Bing, W. U., Ortiz-Aparicio, J. L., Manzano, J. V. L., Kozlowski, W., Dumanska, J., Pawlina, M., Pietrzak, A., Forero, A. M. C., Quesada, H. T., Sanchez, C. A. E., Amaya, R. C., Bohorquez, A. F. P., Sobral, S. P., Borges, P. P., Hatamleh, N., Puelles, M., Iglesias, A., Lozano, H., Jo, K., Hwang, E., Waters, J. F., Asakai, T., Mariassy, M., Shimolin, A., Sobina, A., Prokunin, S., Morozov, I. V., Dobrovolskiy, V. I., and Aprelev, A. V., "Assay of potassium hydrogen phthalate (CCQM-K34.2016)," Metrologia, 56, (2019). 

2. Ma, L. D., Wu, B., Ortiz-Aparicio, J. L., Segoviano-Regalado, F., GarciaAlcantara, A. B., Valle-Moya, E., Rivera-Sanchez, G., Dumanska, J., Pawlina, M., Pietrzak, A., Kozlowski, W., Borges, P. P., Silva, W. B., Freitas, C. S., Araujo, T. O., Almeida, M. D., Lim, Y., Heo, S. W., Hwang, E. J., Wang, Q., Waters, J. F., Sieber, J. R., Pratt, K. W., Suzuki, T., Hioki, A., Mariassy, M., Hankova, Z., Shimolin, A., Sobina, A., Dobrovolsky, V., Prokunin, S., Aprelev, A., and Frolov, D., "CCQM-K48.2014: assay of potassium chloride," Metrologia, 53, (2016). 

Final reports for Key Comparisons may be found in the Technical Supplement of the journal Metrologia. The reports are free and can be located at

Created February 6, 2009, Updated November 3, 2023