As part of the on-going key comparison BIPM.QM-K1, a comparison has been performed between the Ozone National Standard of the Directorate of Measures and Precious Metals (DMDM) and the common reference standard of the key comparison, maintained by the Bureau International des Poids et Mesures (BIPM), via a transfer standard maintained by the National Institute of Standards and Technology (NIST), USA. The instruments have been compared over a nominal ozone amount-of-substance fraction range of 0 nmol/mol to 500 nmol/mol.

Comparison results have been published in the Technical Supplement of „Metrologia”, the leading international journal in pure and applied metrology, published by IOP Publishing, UK, on behalf of Bureau International des Poids et Mesures (BIPM).
The paper is available at: http://iopscience.iop.org/article/10.1088/0026-1394/53/1A/08006.

The Final report of the Key comparison have now been added to the database of the Key comparisons, maintained by the BIPM, KCDB: BIPM.QM-K1.