Legal metrology deals with measurement units, methods and tools, and guarantees the accuracy of measurements used for commercial transactions.

The metrical offices of the Chambers of Commerce are responsible for guaranteeing, at a provincial level, public faith in any business relation. In other words, they aim at allowing transparent trade operations and promoting market self-control. The activity of such Chambers offices is coordinated with that of the Ministry of Productive Activities, which identifies the characteristics and requirements of the weighting and measuring tools, in compliance with the EU directives in force.
Metrical offices carry out checks both upon the request of metrical manufacturers and users, and autonomously, with inspection purposes.

In fact, their tasks include inspections on measurement tools; metrological control of pre-packed and pre-packaged products; and the granting of hallmarks, marking objects manufactured and put on sale (goldsmiths which are granted the hallmark are entered in the relevant Register).
They also deal with the legal metrology regulation infringements, and metrical inspectors can inflict the financial penalties provided for by the regulations in force.
The Paris-based International Organisation of Legal Metrology (IOLM) was established with a view to favouring trade between countries with different legislations; almost all world countries joined said organisation, which aims at harmonising metrological control procedures.

At a European level, common position no. 51/2003 on measurement tools was defined during the Council meeting of 22 July 2003, whereas with a Directive issued on April 4, 2003, the Ministry of Productive Activities fixed the technical procedures for the periodical check of non-automatic weighting tools and fuel measurement units in petrol stations.