The commercial products used widely in similar situations are called "senior medical alarms" (or "alerts"). There are a number of providers. It is hardware (e

The commercial products used widely in similar situations are called "senior medical alarms" (or "alerts"). There are a number of providers. It is hardware (e.g., waterproof button worn around the neck, communicating wirelessly to a base station which includes a specialized loud speaker phone) plus a data-rich monitoring service. When the button is pushed, the base station connects 24/7 to a service rep who can use the loud speaker phone to converse with the wearer. In case of emergency, the rep has a list of nearby friends and possibly distant family to notify, and also has prepared data on hand to summon the correct local emergency services and tell them how to gain access. Monitoring services offer other functions, including calling the senior's base station regularly just to check in and chat briefly, or calling to prompt and check on specific medication. Additional hardware is available, such as motion detectors which activate the base station in case of unusual or missing activity, and multiple units to cover larger living spaces. A lot of development has gone into solving this specific problem, so possibly specialized service would work better than just an intercom.