One of the few surprises of yesterday's Made by Google event was the announcement of revised Nest Aware subscriptions scheduled for early 2020. They include all the Nest devices you use and use Nest speakers and displays as ears that listen for smoke or CO alarm. All new plans also have an emergency call that allows you to call 911 directly from your smart home devices or forward a call from home to your residence's local emergency dispatch dispatcher.
If you're at home and can not reach your phone, you can simply tell one of your Nest Aware's covered speakers or displays to "call 91
If you are absent and your Nest camera or device detects something with Sound Detection turned off Incorrect, you will receive a notification as usual. In addition, an option to call 911 directly from the new feed appears in your Google Home app. This will take you to a call center near your home so that rescue workers can be sent to your home without any problem.
Currently, all emergency call features are only available in the US, and the first subscribers to the new Nest Aware plan have won not understand. It also looks as if 911 calls to ordinary users of Google's smart home devices without a Nest Plan are out of the question. This may be related to the address verification associated with billing, so you can not use and replace another user's address. However, Google should have different authentication methods.