Apple has published a support document outlining the new “fall detection” feature on the Apple Watch Series 4, most notably pointing out, as reported by MacRumors, that the feature will only be automatically enabled for users who have identified themselves as 65 or older when setting up the Apple Watch or the Health app. Other users can enable the feature manually, however, by visiting the “Emergency SOS” section of the iPhone Watch app.

The support document also provides more details on the Fall Detection feature, which Apple introduced at its launch event earlier this month, noting that users will be prompted with an alert after a “significant, hard fall” allowing them to call emergency services, acknowledge that they fell, but that they’re not in need of emergency assistance, or responding that they did not in fact fall — presumably the latter two options will be used to help the Watch refine its fall-detection algorithms to avoid false alerts, but also determines whether an actual fall should be recorded in the Health app.
The support document goes on to note that if the Apple Watch detects the user is immobile for more than one minute, a 15-second countdown will begin, during which time haptic feedback and audible alerts will be sounded; if there is no response after the 15-second countdown expires, a standard Emergency SOS call is automatically initiated, which includes calling emergency services and notifying your emergency contacts of your status and location, as defined in the Medical ID section of the Health app.
Apple also adds that Wrist Detection must be enabled on the Apple Watch in order for it to automatically call emergency services.
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