Does the app make mistakes?

[covidshite]

A friend of mine who I was out with a few days ago (at an outdoor venue) has had an alert telling him to self isolate after supposedly being in close contact with a positive case on the day we were out. He hasn't had contact with anyone other than those in our group, yet none of us have had an alert. What could be going on?

He must have just been within the radius of someone for the required length of time to ping his phone.

I’ve heard of people getting alerts from contacts separated by walls (neighbours etc.) but that could only be deduced because people absolutely hadn’t been anywhere but home. If your friend has been out and about I don’t see how he could reliably deduce that the app notification was unreliable.

On the journey? In the loo? Presumably you weren't beside him 100% of the time.

I think he's just surprised that being at an outdoor venue is treated the same as being indoors, and that nobody else on his table got a notification. I guess it must just be that he was sat at one end of the table nearest the infected person on another table 🤷🏼‍♀️

@eurochick well he walked to the venue with his flatmate who didn't get a notification, and I doubt he spent fifteen minutes in the loo. I genuinely thought it was a mistake when he told me, as I thought outdoor venues were treated differently to indoor.

I don't think the app knows whether someone is indoors or outdoors.

The app doesn’t differentiate between outside/inside, it’s a straight measurement of how close you are to someone and time spent in their vicinity. I think it even counts multiple contacts within a certain time frame so if you crossed paths with someone multiple times in a fifteen minute supermarket visit you’d get pinged.

I got a ‘close contact but not close enough to worry’ message last year that I’m pretty certain came from the drive through test centre. I’ve had to go a couple of times since and made sure to turn my app off.

I don't have the app so don't know all the details but I've read lots of threads on here since the day it was introduced about people not knowing how or why they could have got a notification.

The impression I've got it's that it's not unusual at all

I got a close contact notification just before Xmas. I work in a school and our bags with phones in were in close proximity. We never were. I still had to isolate just in case but I didn't take it very seriously in all fairness as I knew there was no risk.

It seems ridiculous that it doesn't differentiate between indoor and outdoor as the risks of transmission are obviously much greater in a small enclosed space than outdoors (I wouldn't expect the app to do this, but I'd expect the track and trace team to check it)

it’s a straight measurement of how close you are to someone and time spent in their vicinity

No, it's not even that, it's a measurement of signal strength of other devices, and it's actually likely that you need to be further away outdoors for the same considered closeness as indoors (more furniture etc. getting in the way.

Track and Trace are in no way involved in the app's automated alerts.

Goodness is anyone still using this Tory donor created crappy app? It doesn't work and it's a giant waste of tax payer money.

Ignore it, it's full of bugs. Your friend doesn't have to isolate.