International legal metrology
Source: gov.uk (2025-05-01)

How OPSS contributes to international legal metrology and who to contact.

Introduction

The Office for Product Safety and Standards (OPSS) co-ordinates input into international forums including the International Organization of Legal Metrology (https://www.oiml.org/en) (OIML).

OPSS aims to positively influence international legal metrology forums to benefit UK businesses, their customers and consumers. This is done by active participation in several international committees covering areas of interest to UK businesses and consumers. OIML is working towards ensuring a level playing field and reducing technical barriers to international trade.

As well as providing the government to government point of contact for weights and measures, OPSS actively participates in OIML with the aim of influencing regulatory requirements internationally in accordance with the wishes of UK stakeholders, including manufacturers, legislators, and enforcement authorities.

Read the latest OIML bulletins (https://www.oiml.org/en/publications/bulletin) to understand more about the work of OIML.

The role of OIML

The International Organization of Legal Metrology (OIML) is an intergovernmental body, established in 1955. Its main objective is to achieve international harmonisation for legal metrology, providing an important basis for measurement credibility, eliminating technical barriers to trade in measuring instruments and promoting international trade by confidence in measurement capability.

OIML produces international recommendations (https://www.oiml.org/en/publications/recommendations/publication_view?p_type=1&p_status=1) which are similar to technical standards and provide the basis for laws regulating measuring equipment, and quantity control and quantity labelling pre-packages. Other OIML publications such as international documents (https://www.oiml.org/en/publications/documents/publication_view?p_type=2&p_status=1) give guidance on establishing a legal measurement system. These recommendations and documents are drawn up in technical committees consisting of experts from OIML Member States and Corresponding Members. OPSS’s role is to facilitate the development and approval process of these recommendations and ensure that UK legal metrology interests are fully represented.

There are currently 64 Member States and a further 66 Corresponding Members that make OIML influential in harmonising world legal metrology requirements.

UK OIML participation

UK is a Member State in OIML and is represented in OIML by the UK International Committee of Legal Metrology (CIML) Member.

On behalf of the UK interests, OPSS operates some of the OIML Technical Committees (TC) and Sub-Committees (SC). The following table provides contact details should you wish to get involved and contribute to OPSS’s OIML activities.

UK participates in other OIML committees that are of national interest, such as TC 3 Metrological control (https://www.oiml.org/en/tc-sc-pg/scinfo_view?idsc=52), TC 6 Prepackaged products (https://www.oiml.org/en/tc-sc-pg/scinfo_view?idsc=55), and TC 8 Measurement of quantities of fluids (https://www.oiml.org/en/tc-sc-pg/scinfo_view?idsc=57). Visit the OIML website to see the complete list of technical committees and subcommittees (https://www.oiml.org/en/tc-sc-pg/tclist_view).

Recent OIML developments involving OPSS include the publication of the new international legal metrology standard, OIML R 49:2024 “Water meters for cold potable water and hot water” (https://www.oiml.org/projectedit_view?idproject=493).

OIML Certification System (OIML-CS)

The OIML Certification System (OIML-CS) is a system for issuing, registering and using OIML certificates and their associated OIML type evaluation/test reports for types of measuring instruments, based on the requirements of OIML Recommendations.

OPSS represents the UK in the OIML Certification System (OIML-CS) as a Utilizer. This means that the UK will accept and utilize OIML type evaluation and test reports for type approval when associated with an OIML certificate issued by an OIML Issuing Authority. This is subject to Additional National requirements (ANRs).

More information on obtaining and using OIML-CS certificates is available on the OIML-CS website (https://www.oiml.org/en/oiml-cs/information-for-manufacturers).

The UK OIML Utilizer scope can be found on the OIML Utilizers and Associates list (https://www.oiml.org/en/oiml-cs/docs/oiml-util-and-assoc-summary-table.pdf).

UK OIML point of contact

Ms Sophie GeorgeUK CIML MemberOffice for Product Safety and StandardsStanton AvenueMiddlesexTW11 0JZEmail: xxx@xxx.xx (mailto:xxx@xxx.xx)

Mr Morayo AwosolaUK CIML AssigneeOffice for Product Safety and StandardsStanton AvenueMiddlesexTW11 0JZEmail: xxx@xxx.xx (mailto:xxx@xxx.xx)