If you are responsible for legal metrology, you need to have access to appropriate local & working standards and report your enforcement activity annually to the Office for Product Safety and Standards (OPSS). Operational support and training opportunities are available.

Maintaining standards

Specifications and technical guidance for standards used by local authorities for weights and measures are published by OPSS.

Legal metrology: standards specifications (7000 series)

Each local authority must have access to a full set of local standards that can be traced to the secondary and tertiary standards we maintain. Local standards should be used under controlled conditions to calibrate working standards and test equipment.

A local authority can have its own local standards or use those of another local authority. We must approve these agreements, which should be in writing. We should also be informed if they are changed. It is possible to have arrangements with more than one local authority.

Please use the forms below if relevant:

Application for approval for a nil or partial holding of local standards (ODT, 24.7 KB)

Notification of a variation of an arrangement for a nil or partial holding (ODT, 25 KB)

Local authorities must have sufficient access to local standards, maintain sufficient working standards and test equipment to meet local needs, and provide an impartial inspection and re-qualification service. We test local authority local standards to ensure they are calibrated accurately.

We provide a statutory calibration service to local authorities for mass, length and volume standards.

Legal Metrology Delivery: standards calibration

Gaining and maintaining approved body status

OPSS has developed a non-accredited peer auditor scheme for local authorities to gain and maintain approved body status. The protocol lays down a framework for local authority approved bodies to be independently audited to meet the standard set by the Secretary of State for conformity assessment of instruments under the Non-Automatic Weighting Instruments Regulations 2016 and the Measuring Instruments Regulations 2016.

Approved bodies can be found listed on the UK Market Conformity Assessment Bodies database

• LA Approved Body audit schedule 2024-2030 (ODS, 4.985.14 KB)
• LA Approved Body peer audit protocol 2024 (PDF, 233 KB, 13 pages)
• LA Approved Body peer audit form 2024 (ODT, 17.3 KB)
• LA Approved Body peer auditor list 2024 (ODS, 5.44 KB)

Enforcement reporting

The level of your local weights and measures enforcement work conducted over 12 months needs to be reported to OPSS in April each year.

Legal metrology: local enforcement reporting

Operational support and advice

OPSS has a dedicated coordination team that helps local authorities regulate legal metrology. Its remit includes policy, intelligence, investigation, equipment approval, technical requirements, and consumer engagement.

To make an enquiry please email: OPSS.enquiries@businessandtrade.gov.uk

Legal metrology: list of regulations

We publish guidance for businesses on the regulation of weights and measures equipment, which is also relevant to local regulators.

Weights and measures equipment guidance

Local authorities often ask for our views on technical issues that impact on types of equipment or groups of organisations. Our determinations on these technical and enforcement issues are published in bulletins.

Weights and Measures Bulletins

Various other resources for local regulators are available on Regulators’ Companion, including templates, learning opportunities and guidance produced by the National Legal Metrology Group (NLMG).

Legal metrology - Regulators’ Companion website

National projects

In partnership with the National Legal Metrology Group, we co-ordinate national projects led by local authorities.

National metrology project reports

Primary Authority

As a supporting regulator, we help primary authorities to produce advice for their partner businesses and co-ordinators relating to legal metrology, or to develop and manage relevant inspection plans.

To request this support, please complete and return: Primary Authority support request template and service standards

Training opportunities

Courses for local authority practitioners are designed to equip them with the knowledge and skills needed to work effectively with businesses and build consumer confidence in today’s challenging and evolving market place.

Legal metrology learning - Regulators’ Companion website