The contact tracing part of the NHS COVID-19 app, and the venue check-in function, are 2 separate ways that the app protects you from coronavirus (COVID-19). We encourage app users to keep their contact tracing on at all times, and check into all venues where an official NHS QR code poster is available.
When you have contact tracing switched on, your app will use Bluetooth to know when it has come into close contact with other nearby app users. ‘Close contact’ is generally 2 metres for 15 minutes or more. If any of those nearby app users later test positive for coronavirus (COVID-19), you will receive an alert with advice on what to do, for example self-isolate and book a test if you develop symptoms. The alerts are based on a ‘risk-scoring algorithm’ optimised by scientific experts.
When you check into venues using the NHS COVID-19 app and the official NHS QR code poster, this data is held on your phone. If it is later discovered that other people who were at the same venue at a similar time as you, have tested positive for coronavirus (COVID-19), you may get an alert with public health advice on what to do. The people who tested positive will have confirmed to contact tracers that they were at the venue at a certain time.
This alert will not usually be trigged by just one person who tested positive, and it will not usually tell you to self-isolate, just to be aware and to get a test if you develop symptoms. The decision about whether to send an alert will be taken by local health protection teams in line with wider NHS Test and Trace or NHS Wales Test, Trace, Protect policy, it is not an automated decision.