The International Air Transport Association urged countries around the world to adopt the European Union’s Digital Covid Certificate as the global standard for vaccine certification.

The EU’s vaccine passport should serve as the blueprint for other nations, IATA Deputy Director General Conrad Clifford said in a statement Thursday.

While multiple certificates or digital applications testifying to the low-risk status of holders have been developed, there’s so far no global standard. IATA said the DCC is particularly effective because it’s available in paper and digital form, with a QR code that can be read in both, and features a gateway for the distribution of encrypted data that can extended to issuers from outside the EU.

IATA said up to 60 countries are looking to use the DCC specification for their own certification, in addition to the 27 EU members and states with reciprocal agreements, including Switzerland, Turkey, and Ukraine.

The passport also enables holders to access non-aviation sites in Europe that require proof of vaccination, such as museums, sporting events and concerts.