#1. Legislative History
N. 1 Federal competence for metrology has a long tradition in Swiss constitutional law. Already Art. 37 of the Federal Constitution of 1848 transferred legislation on measures and weights to the Confederation. This competence was continued in Art. 40 para. 1 old FC and was adopted in 1999 in its present formulation in Art. 125 FC (Brunner, SG Comm. FC, Art. 125 N. 1).
N. 2 The message on the new Federal Constitution emphasised that the regulation of metrology represents a classic federal task which serves legal harmonisation and the protection of honest business transactions (Message FC, FG 1997 I 1, 368). The constitutional revision of 1999 did not lead to any material change in federal competence, but merely adapted the terminology to modern circumstances.
#2. Systematic Classification
N. 3 Art. 125 FC is found in Title 3 on the Confederation, Cantons and Communes, in Chapter 2 on competences. The provision establishes an exclusive federal competence, as follows from the wording "is a matter for the Confederation" (→ Art. 3 FC). The cantons have no residual legislative competence in the area of metrology.
N. 4 The metrology competence stands in systematic connection with economic freedom (→ Art. 27 FC) and federal competence for private law (→ Art. 122 FC). It serves the realisation of the unified economic area of Switzerland (→ Art. 95 FC) through standardisation of units of measurement (Häfelin/Haller/Keller, Federal Constitutional Law, N 1254).
#3. Elements of the Offence / Content of the Norm
N. 5 The concept of "metrology" encompasses, according to prevailing doctrine, three areas: (1) the definition of units of measurement and their standards, (2) the requirements for measuring instruments and measuring procedures as well as (3) the supervision and calibration of measuring devices (Vaucher/Niederhauser, METinfo 3/2007, 10 ff.).
N. 6 Federal competence extends to all types of measurements in commercial transactions, regardless of the object measured. This covers physical quantities such as length, mass, time, temperature, electric current, amount of substance and luminous intensity as well as units derived from them (Art. 2 para. 1 MIA; Art. 3 ff. Units Ordinance).
N. 7 However, evaluations and estimates without a physical measurement basis as well as purely private measurements without reference to commercial transactions do not belong to metrology within the meaning of Art. 125 FC (Aubert/Mahon, Petit commentaire, Art. 125 N. 3).
#4. Legal Consequences
N. 8 As an exclusive federal competence, Art. 125 FC excludes any cantonal legislation in the area of metrology. The Confederation has exercised its competence through the Federal Act on Metrology (MIA) and its implementing decrees.
N. 9 The cantons are restricted to the implementation of federal law. They may act as calibration offices insofar as federal law provides for this (Art. 15 para. 1 MIA). They may not enact their own material provisions on metrology (BGer 2C_1007/2015 consid. 3.2).
N. 10 Private parties are subject to the calibration obligation for measuring instruments in commercial transactions (Art. 3 MIA). However, the choice of measurement service provider remains protected by economic freedom, insofar as no legal monopoly exists (BGE 143 I 395 consid. 4.3).
#5. Disputes
N. 11 The scope of federal competence for new measurement technologies is disputed. While Vaucher/Niederhauser/Richard (METinfo 1/2008, 4 ff.) advocate an application-oriented approach that also fully encompasses intelligent measurement systems, other authors represent a more restrictive interpretation for purely digital measurement procedures without a physical component.
N. 12 The relationship between metrology competence and data protection is also controversially discussed. The METAS database contains sensitive information about measuring device owners. Zen-Ruffinen (FC 1874, Art. 125 N. 8) demands a strict separation between measurement technology and data protection aspects, while practice prefers an integrative approach (FDPIC recommendation of 18.2.2014).
#6. Practical Guidance
N. 13 When introducing new measuring devices, the calibration obligation under Art. 3 MIA must be observed. METAS as the Federal Office of Metrology is the first point of contact for questions on conformity and approval (Art. 15 para. 2 MIA).
N. 14 Companies should observe the transitional periods when replacing measuring devices. The Federal Administrative Court examines the proportionality of replacement orders and takes into account the economic interests of those affected (BVGer A-272/2013 consid. 5.3).
N. 15 In the area of electricity measurement, there is no legal monopoly for measurement services. Grid operators cannot compulsory perform the measurement themselves, but must respect the economic freedom of producers (BGE 143 I 395).