Effective as of September 21, 2020
About California COVID Notify
California COVID Notify allows users to send and receive notifications of a potential high-risk exposure to COVID-19, in a privacy-preserving manner. The notifications will include instructions on who to contact and next steps to take.
The exposure notifications are intended to supplement the conventional contact tracing efforts undertaken by local public health authorities involving contact by a caseworker.
How it works
California COVID Notify does not collect or exchange any personal information, as defined in the California Information Practices Act, of the user to receive notifications.
The mobile devices of users share anonymous keys (randomly generated strings of numbers) via Bluetooth. The only data used are the anonymous keys, Bluetooth signal strength (proximity), and date and duration of exposure. These data are not linked to a user’s identity or location. Each user’s keys change frequently to further protect their identity. These data are stored only on the user’s own device and are never shared unless and until the user has a positive COVID-19 diagnosis and elects to share this information within the system. The data are stored for a period of 14 days and then automatically deleted. Once deleted the data cannot be restored.
A user who tests positive for COVID-19 may choose to notify other California COVID Notify users who have been near the user. To trigger such notification, the COVID-19 positive user must enter a valid verification code provided by the medical provider, lab, or local public health authority.
Several times a day, the app downloads a list of all the anonymous keys associated with positive COVID-19 cases that have elected to share their keys via the app. The user’s device checks these keys against the list of keys it has encountered in the past 14 days. If there is a match, and the date, duration, and proximity align with the public health authority’s risk model to indicate a possible exposure to the virus, the user will receive an exposure notification.
The notification will inform the user of the date of exposure and instructions on what to do next.
User consent & choices
Using the system
California COVID Notify has the potential to help stop the spread of the infection and its use is highly encouraged, but it is completely voluntary.
Users may turn the system on or off at any time, or uninstall the app on an Android device. The system does not collect, track or store users’ location, GPS information, or personal information.
Disabling exposure notifications
Users may disable California COVID Notify at any time by uninstalling the app (Android), turning off the feature (iOS), turning off the mobile device, or turning off the Bluetooth function.
Generating exposure notifications to other users
Providing notification to other users is also completely voluntary. If a user tests positive for COVID-19, and chooses to notify others, the user has to activate notifications by entering a verification code to release the anonymous keys stored on the mobile device. When anonymous keys are released, the notifications that may be generated do not disclose the COVID-19 positive user’s identity, location, phone number, or any other personal information.
The exposure notification includes the date of the exposure, but the COVID-19 positive user’s identity is not shared. Sharing the exposure date is important to ensure the right precautions (such as self-quarantine) are taken for an appropriate amount of time based on the exposure date. It is possible that someone who receives an exposure notice could guess the identity of the COVID-19 positive individual, if they had a limited number of contacts on a given day.
A verification code is required to share a positive test result in the system. This ensures that only verified positive test results are used to generate exposure notifications. Verification codes may only be generated by a medical provider, lab, or public health authority.
Sharing of information
The following categories of de-identified data may be processed and collected by California COVID Notify:
- Installing the app
- Enabling and disabling exposure notifications
- Receiving an exposure notification
- Entering a verification code to send anonymous keys
- Anonymous keys that have been voluntarily shared
- Deleting the app
The data may be used to monitor system usage, as well as for performance evaluation and statistical or scientific research purposes. The data may also be shared with local public health authorities and the University of California. This information will not include any personal or location information, nor can it be used to identify any system user.
California COVID Notify is not intended for children under the age of 13. Users between the ages of 13 and 17 can only use the system after the parent or legal guardian has reviewed and provided consent.
California Department of Public Health
PO Box 997377, MS 0500
Sacramento, CA 95899-7377
CDPH Conditions of Use