“an alert notification system that allows mobile device users to receive an alert when they may have been exposed to someone who has tested positive for COVID-19”

From the Mayor’s Office:

“Today, Mayor Muriel Bowser is urging DC residents who use iPhone or Android smartphones to opt-in to DC COVID Alert Notice (DC CAN), an alert notification system that allows mobile device users to receive an alert when they may have been exposed to someone who has tested positive for COVID-19. DC CAN is the official COVID-19 exposure notification app for Washington, DC.

“We are encouraging all District residents, and those who spend time in the District, to opt into DC CAN,” said Mayor Bowser. “Using the DC CAN system is a quick and easy way to know if you might have been exposed to COVID-19. Opting in is one more way you can protect yourself, your friends and family, and our entire community.”

Beginning today, DC residents with iPhone or Android smartphones will receive a push notification inviting them to opt into exposure notifications. On iOS, users will be able to opt into exposure notifications through settings without having to download an app. On Android, users will be prompted to opt in and install the DC CAN app from the Google Play Store. Additionally, at any time, users can also go directly into their iOS settings to enable the system or go to the Play Store to download the DC CAN app.

“This technology was created for the sole purpose of helping us stop the spread of COVID-19. Knowing your exposure history allows you to self-quarantine quickly, seek medical attention, and reduce the potential of exposing others,” said Dr. LaQuandra S. Nesbitt, Director, DC Health. “DC CAN is another tool helping our contact tracing efforts in the District. The Exposure Notifications System will be disabled once the pandemic reaches a point that no longer necessitates the use of this technology.”

Once you opt-in to the notification system, the Exposure Notifications System will generate a random ID for your device. To help ensure these random IDs can’t be used to identify you or your location, they change every 10-20 minutes. Your phone and the phones around you will work in the background to exchange these privacy-preserving random IDs via Bluetooth. You do not need to have the app open for this process to take place. Your phone periodically checks all the random IDs associated with positive COVID-19 cases against its own list. If there’s a match, you will receive a COVID-19 exposure notification, with further instructions from DC Health on how to keep you and the people around you safe.

For COVID-19, a close proximity is anyone who was within six feet of an infected person for at least 15 minutes. An infected person can spread COVID-19 starting from 48 hours (or two days) before the person had any symptoms or tested positive for COVID-19.

DC CAN protects users’ privacy and data security. The Exposure Notification System does not track the users’ location. Google, Apple, or other users cannot see the user’s identity and only public health authorities can use this system. Users can choose to share their information for public health purposes only and you can optionally provide your phone number so that a contact tracer may follow-up. Users’ information will not be shared with any other agencies like law enforcement or immigration. Users can also choose not to share any personal information and still use the system privately and anonymously.

For more information about DC CAN, visit coronavirus.dc.gov/dccan. For more information about EN Express visit www.google.com/covid19/exposurenotifications/.”