Ключевые слова: app, certification, certified, concept, crown, danger, digital, distance, document, epidemic, europe, european, european union, face mask, ffp2, green pass, health, health care, health passport, immune, immune passport, infection, mask, medical, pandemic, pass, passenger, passport, prevention, protection, protective, qr code, restrictions, safety, social distancing, surgical, tourism, train, travel, travel pass, traveler, traveling, vaccination, vaccine, vaccine passport,