Safer Illinois, Exposure Notifications

How does the exposure notification feature work in Safer Illinois? Why does it ask for location access?


To participate in exposure notification, you must:

  1. Enable the Exposure Notification feature during the app setup or in the Settings menu
  2. Allow Safer Illinois to use Bluetooth and location services when prompted
  3. Allow Safer Illinois to display notifications
Safer Illinois generates local notifications to keep the Bluetooth scanning system engaged while your phone is locked or while exposure notification is working in the background. Your phone may display a notification that says "Checking for exposures..." while exposure notifications are enabled.

screenshot of the notification the app generates

On Android, enabling exposure notification adds an icon exposure notification status bar icon on androidto your status bar to indicate it's running in the background.

How do I know that Exposure Notification is working?

Your device will tell you when Exposure Notification is running. On iPhone, an alert message is displayed periodically that says “Checking for Exposures” when the Exposure Notification functionality is enabled. On Android, the notification screen says “Privacy-preserving contact tracing is currently running.” 

Our system analytics tell us that Exposure Notifications are being reported anonymously to campus-based users of Safer Illinois.

What distance and time constitutes a "contact" for Exposure Notification?

Exposure Notification is triggered only by a contact that is considered a likely risk. Not every person you are near will be evaluated to determine exposure risk. The distance and time thresholds for registering a “contact” are currently set to a proximity of 10 feet and a duration of 2 continuous hours (August 20, 2020 release v.2.3.5). These settings are adjusted by local health authorities as they evaluate the effectiveness of the Exposure Notification system. Exposure risk settings are calibrated to strike a balance between too sensitive (producing false alarms) and not sensitive enough (failing to warn of actual exposures).

It is important to understand that the automated Exposure Notification feature of Safer Illinois is not a form of contact tracing. Champaign-Urbana Public Health District (CUPHD) performs human contact tracing on our campus. Individuals who have a COVID-19 infection are interviewed by public health personnel to find out the names of their recent contacts. Those contacts are then interviewed by the contact tracing personnel and given medical guidance.

Why does Safer Illinois need to access my location?

We are not using any location information in Safer Illinois.  It’s not stored, nor is it sent off the device.
iOS and Android require Safer Illinois to ask for location services permissions to use Bluetooth in exposure notifications.
Read more in our Privacy Policy at the Safer Illinois website.

Why doesn't Safer Illinois use the Exposure Notification API developed by Apple and Google?

Safer Illinois uses an exposure notification system developed by Dr. Sanjay Patel with several other researchers and students in the Grainger College of Engineering Department of Electrical and Computer Engineering. Their efforts and developments were guided by input, oversight, and contributions from security and privacy experts all over campus.

We have been in discussions with Apple and Google about the importance of Safer Illinois to our community. At this time, we are awaiting an entitlement from Apple and Google which would allow us to use their APIs. 




Keywords:contact tracing exposure notification bluetooth location tracking permission permissions gps   Doc ID:104692
Owner:Isaac G.Group:University of Illinois Technology Services
Created:2020-08-05 21:05 CDTUpdated:2020-08-26 21:02 CDT
Sites:University of Illinois Technology Services
Feedback:  14   3