The DVPAK also includes a personal trigger and a range of additional sensors, including fall and movement detectors, and "bogus caller buttons." These buttons are located on the lifeline unit, which is positioned by the doorway, and provide users with a means to alert police without using a phone when an unwanted visitor is trying to gain access to the home by posing as a legitimate caller such as a delivery person.
The fall and movement detectors are a series of passive infrared detectors positioned around the home, similar to the sensors used with burglar alarms. The detectors can be programmed to detect movement after a certain time and can also detect inactivity within a predetermined time period.
The sensors are registered to the central lifeline home unit, which picks up radio signals from the sensors and from the personal trigger worn on a user's body. The lifeline unit also contains a powerful speaker to allow hands-free communication with the police operators from anywhere in the home or garden, and can be programmed to record all conversations. The recordings can be used as evidence, if necessary. -- Tunstall