The International Air Transport Association’s Travel Pass will use blockchain technology to encrypt users' data, eliminating the possibility of it being tampered with. The digital health passport is a mobile app that allows travellers to share Covid-19 test and vaccine certificates with airport authorities, airlines and governments. However, users will stay in control of their data and decide the amount of information they would like to share, according to Alan Hayden, Iata’s head of airport, passenger and security products. “The passenger owns their data, and they share it with the airline ... it is so powerful and it is probably one of the first examples of blockchain technology being implemented in a way that benefits people,” Mr Hayden told Future Travel Experience, an independent travel events’ organiser and media portal in Surrey. There will be no central database or data repository to store Travel Pass data and the app is being built in accordance with the self-sovereign identity principles, the airline industry body said. The SSI model recognises a person's right to manage and control their digital identity and data without intervention by administrative authorities. “Governments are focusing on everybody getting vaccinated as a health issue, but the other part of the equation is the proof of vaccination ... what we need are electronic vaccination certificates,” said Mr Hayden. “This is the only thing that will make society free again to do all the things it needs to do.” Iata is also working with the World Health Organisation and other bodies to come up with the necessary standards. The Travel Pass is being developed in four independent modules that can interact with each other. These include a global archive with information regarding passengers’ regulatory entry requirements, a registry of certified labs and vaccination centres, a dedicated lab app that allows authorised testing centres to send reports and vaccination reports directly to users and a digital passport module. These four modules are designed to be offered as part of the airline’s own mobile application. They can either work separately or together, depending on the user's choice. “Within the airline app, passengers will be able to create a digital version of their passport,” said Mr Hayden. “Once the passenger has a digital version of their passport on their phone, they will go to the laboratory and scan a code, which creates a link between the passport details and the laboratory.” The UAE's <a href="https://www.thenationalnews.com/business/aviation/etihad-airways-and-emirates-to-trial-iata-s-travel-pass-1.1149056">Etihad Airways and Emirates</a> are already working with Iata to adopt its Travel Pass. Etihad said that its passengers will be able to use the app in the first quarter of this year. Emirates will begin trials in April before fully adopting it across its network. Singapore Airlines <a href="https://www.singaporeair.com/en_UK/ae/media-centre/press-release/article/?q=en_UK/2020/October-December/ne2420-201223">said </a>it was the first operator to trial the app last month. The service was initially offered to passengers flying from Jakarta or Kuala Lumpur to Singapore from December 23.