The French legislation defines two types of limits for alcohol: one for alcohol in blood and one for alcohol in breath. These two methods are legal. Evidential breath analysers are used for determining alcohol concentration in breath. In France they are considered as legal metrological instruments and they are subjected to a specific legislation. The current French legislation is based on a French national standard. The specifications of this legislation are not very far from the OIML Recommandation R 126. However, the French legislation deals only with non-portable breath analysers, which are used within buildings. The evidential breath analysers are submitted to different legal metrological control operations: 1) The pattern approval which is delivered by the "sous-direction de la metrologie" of the ministry of industry. The tests for pattern approval are performed by a laboratory named by the ministry of industry. This laboratory is LNE; 2) The initial verification is performed on each instrument before bringing them in service. This verification is also performed by LNE named by the ministry for this operation; and 3) the periodic verification is performed every twelve months on each instrument. The check is done by ten accredited laboratories. For all this checkings, a specific test rig similar to the one described in the OIML Recommandation is used to get the conventional true value of the gas concentration. Please note that the conference proceedings do not contain any paper and that this abstract is the only contribution.