Our Work

Metrology in Chemistry

Metrology is the science of measurement and its application. As one of the branches of metrology, metrology in Chemistry focuses on the study of comparability and traceability of chemical and biological measurements to ensure the reliability of results. This is essential in establishing global mutual recognition of analytical results, thereby providing a technical foundation for wider agreements related to international trade, commerce and regulatory issues. Comparability and metrological traceability are normally established through participation in inter-comparisons organised by international or regional metrology organisations like the International Bureau of Weights and Measures (BIPM) and the Asia Pacific Metrology Programme (APMP), as well as through the use of certified reference materials (CRMs).

The Government Laboratory (GL) has been actively involved in international metrology activities since the 1990s. It is one of the founding members of the Co-operation on International Traceability in Analytical Chemistry (CITAC) established in 1993. In 2004, the GL became a full member of the APMP, formalising its participation in international activities related to metrology in chemistry. Since May 2005, the GL has been appointed as a Designated Institute (DI), in the field of metrology in chemistry for Hong Kong, China, under the Mutual Recognition Arrangement of the International Committee for Weights and Measures (CIPM MRA). DIs are specialist institutes appointed by government, an appropriate authority, or in some cases the National Metrology Institute (NMI) itself, to deal with metrological responsibilities for certain national standards and associated services that are not covered by the activities of the NMI. In fulfilling its commitments for being a DI, the GL has been accredited as a proficiency testing provider and reference materials producer since August 2006 and December 2010 respectively. In 2012, the GL became the official observer under the Consultative Committee for Amount of Substance: Metrology in Chemistry and Biology (CCQM), in recognition of its expertise in this area.

Moving forward, the GL, as the designated institute representing Hong Kong, China, in the field of metrology in chemistry, will continue to participate actively in meetings, workshops, symposiums, and comparison studies organised by international and regional metrology organisations. Through these exchanges, the GL has built a robust foundation in scientific measurement and continues to contribute to the prosperity and development of Hong Kong as well as to international trade, commerce and regulatory affairs.

Calibration and Measurement Capability (CMC) Claims

With the support of satisfactory results obtained from key or supplementary comparisons organised by international / regional metrology organisations, NMIs or DIs are eligible to apply for CMC claims. These CMCs are published in the BIPM Key Comparison Database (KCDB) under the CIPM MRA. https://www.bipm.org/kcdb/

The CMCs allow countries and economies worldwide to recognise each other’s measurement standards and calibration certificates. Through the CMCs, institutes can disseminate traceability to their customers through services such as:
1. provision of calibrations or reference value;
2. provision of CRMs.

The list of CMC claims obtained by the GL can be downloaded from the link:
https://data.gov.hk/en-data/dataset/hk-govtlab-cmc-cmc

Reference Materials Production

As a DI for metrology in chemistry for Hong Kong, China, under the CIPM MRA, the GL has the responsibility of disseminating traceability of chemical and biological measurements to local laboratories. Through the provision of CRMs with property values traceable to stated references, the GL continues to disseminate traceability to concerned parties. By using of appropriate reference materials, testing laboratories can validate their analytical methods and establish the traceability of their measurements.

In December 2010, the GL was accredited as a reference material producer in accordance with the international reference ISO Guide 34:2009. Over the years, the GL has commissioned the production of several reference materials, including those for trace elements in herb and seafood, pesticides in tea, melamine in milk, and high purity melamine. These reference materials were produced to support the local testing industry as it was challenging for testing practitioners to source similar reference materials that were fitted for their intended operations. In January 2019, the GL successfully transitioned its accreditation to the latest international standard, ISO 17034:2016, for reference material producers.

The reference materials produced by the GL are available to testing laboratories, normally free of charge, under the following conditions:

1. to support testing laboratories in Hong Kong in seeking accreditation;
2. to support the outsourcing activities of the GL;
3. to fulfill the GL’s commitments as a DI under the CIPM MRA; and
4. other conditions at the discretion of the Government Chemist.

If you have any enquires about the reference materials produced by the GL, please contact us.

International Collaboration

As a member of the international metrology community, the GL keeps close contact with other national metrology institutes through regular participation in related meetings and technical exchanges. Besides, the GL continues to collaborate with local and mainland inspection authorities, as well as overseas testing and metrology institutes, to promote chemical metrology in the region. Recent collaboration programmes are summarised in the attached table.