Contact Harald is a contact tracing system that uses Bluetooth®-enabled tracing cards (worn on a lanyard or clip) for people moving about within a defined area such as a building. Each person issued a Contact Harald card consents to provide their name and contact details (mobile phone number and/or email address). These details are stored on a secure, encrypted database – not on the card itself. A close contact is registered when two or more people wearing a Contact Harald card come within 2 metres (6 feet) of each other for a minimum period of 2 minutes. This contact data is downloaded from the cards to the encrypted database.