Léonie Lebain
Areometry allows for the determination of the density or specific gravity of a liquid using a floating instrument: the areometer. In the field of alcoholic beverages and hydroalcoholic solutions, alcoholometers are commonly used to determine the alcoholic strength of a mixture of water and ethanol.
But when these instruments are used in a regulated context, their precision is not enough: they must also meet the requirements of legal metrology.
What does legal metrology mean?
In France, legal metrology constitutes the regulatory framework used to guarantee the reliability of measurements, particularly in commercial transactions, tax operations, health, safety, or for determining or verifying declared or imposed characteristics.
The main reference text is Decree no. 2001-387 of May 3, 2001, on the control of measuring instruments.
Article 1 specifies the various operations for which the instruments concerned are subject to this regulatory framework. Annex I provides a list of the categories of instruments covered, among which are alcoholometers, alcohol areometers, and alcohol tables.
Thus, not all uses of an alcoholometer necessarily fall under legal metrology. It is the use made of the measurement that determines the applicable regulatory requirements.
What are the rules for placing alcoholometers on the market?
The decree distinguishes between different regimes.
Title II concerns instruments subject to a European directive. Title III defines the provisions applicable to the placing on the market and putting into service of other instruments covered by the decree, including alcoholometers under the national framework.
For their placement on the market, two requirements are particularly important: the type examination certificate and initial verification.
The type examination certificate
The type examination allows for verification that the design of an alcoholometer model meets the applicable regulatory requirements (Decree no. 79-200 of March 5, 1979, and the order of May 11, 1979).
When this examination is successful, a type examination certificate is issued by the LNE. It thus attests to the conformity of the instrument type examined with the texts in force.
Initial verification
Initial verification then allows for the checking of manufactured instruments before they are placed on the market to ensure they meet the regulatory requirements and correspond to the approved type.
This verification can be carried out by the manufacturer when their quality assurance system is approved and supervised by the designated body.
It can also be carried out by an approved body for this category of instruments. To date, however, there is no approved body for the initial verification of alcoholometers.
Thus, a manufacturer without either a valid type examination certificate or a quality system approved by the LNE cannot place on the market alcoholometers intended to be used within the scope of Decree no. 2001-387.
The role of the LNE
The order of August 22, 2001 designates the Laboratoire national d'essais, now the LNE, for various metrological control operations of national effect.
It intervenes particularly for:
- type examination of measuring instruments;
- approval and supervision of quality assurance systems for manufacturers or repairers;
- approval and supervision of quality assurance systems for installers where applicable.
Type examination certificates as well as information regarding certified bodies and manufacturers in legal metrology can be consulted in the database of certificates issued by the LNE.
This verification allows professionals in particular to ensure that the instrument chosen indeed meets the requirements corresponding to its use.
Calibration and regulatory compliance: two different concepts
A calibration certificate does not automatically mean that an alcoholometer meets the requirements of legal metrology.
Calibration allows for the determination of measurement deviations of an instrument compared to a reference. Regulatory compliance, on the other hand, concerns the conditions under which the instrument is designed, manufactured, checked, and placed on the market.
For use falling under legal metrology, it is therefore essential to verify that the instrument indeed possesses the necessary regulatory guarantees.
Choosing your alcoholometer with Dujardin-Salleron
Dujardin-Salleron offers French-made alcoholometers for professionals in the wine, spirits, and beverage industries, adapted to various measurement and control needs. The conformity of all our alcoholometers is ensured by type examination certificate no. 37127. Their manufacture is also covered by a quality system approval certificate no. 37139.
Our offering includes in particular the 173 range, comprising our Class II precision alcoholometers, available in different measurement ranges (in increments of 10% vol.), as well as our range of special-scale alcoholometers, such as the 15–22% vol. models intended in particular for the measurement of spirits with an alcoholic strength of over 18% vol. This range completes our offering to meet specific measurement needs.
This diversity of models allows every professional to have an alcoholometer adapted to their measurement requirements, combining precision, reliability, compliance, and traceability.
