What types of ALDs (Assistive Listening Devices) are there?
There are two categories of ALD: alerting devices and listening devices. An alerting (or alarm) device indicates that something important is occurring (smoke detector, carbon monoxide detector, alarm clock, door bell, baby monitor). An alerting device can indicate that something important is happening by producing extra loud sound, light, vibration or a combination of some or all of these. A listening device facilitates the reception and understanding of sound and spoken language. These types of ALDs are used for the telephone, television, movies, theater, museum tours, lectures, and noisy situations.
