Article 3
1. Boatmasters' certificates which are still in force and are listed in Group A in Annex I shall be recognized by all Member States as valid for the purposes of navigation on the waterways of a maritime character listed in Annex II, as if they had issued the certificates in question themselves. 2. Member States shall reciprocally recognize the boatmasters' certificates which are still in force and are listed in Group B of Annex I as valid for the purposes of navigation on their inland waterways apart from those for which the Rhine navigation licence is required or which are listed in Annex II, as if they had issued the certificates themselves. 3. Recognition by a Member State of a boatmasters' certificate listed in Group A or Group B of Annex I may be made subject to the same miminum age conditions as those laid down in the Member State in question for the issue of a boatmasters' certificate in the same group. 4. Recognition by a Member State of a boatmasters' certificate may be limited to those categories of vessels for which this certificate is valid in the Member State which issued it. 5. Subject to consultation of the Commission and the other Member States, a Member State may require that, for the purposes of navigation on certain waterways other than the waterways of a maritime character as indicated in Annex II, boatmasters from other Member States satisfy additional conditions concerning knowledge of the local situation equivalent to those required for its national boatmasters. 6. This Directive shall not prevent a Member State requiring additional knowledge on the part of boatmasters sailing vessels transporting dangerous substances on its territory. Member States shall recognize the certificate issued in accordance with the number 10 170 of the ADNR as proof of this knowledge.