See Assistive Listening System.

A visual (usually flashing lights) or tactile (vibrating) device that alerts a person who cannot hear to sounds such as door knocks/doorbells, telephones ringing and fire alarms.

See Assistive Listening Device.

The hearing threshold for a pure tone delivered from an earphone or ear inserts.

The transmission of sound through the outer and middle ear to the cochlea.

Transmission of sound to the inner ear by way of the ear canal and the middle ear. In hearing testing, air-conduction testing is performed by sending sounds to the ear though an earphone or loudspeaker.