AS 1428.5:2021 – Design for access and mobility Part 5: Communication for people who are deaf or hearing impaired.
1.3.6
hearing aid
personal device used by people who are deaf or hearing impaired, for amplifying and processing sound, which consists of a microphone, signal processor, amplifier and earphone
Note 1 to entry: A hearing aid is a type of hearing device.
1.3.7
hearing augmentation system
permanently installed and portable hearing loop system, emitting and receiving system, or transmitting and receiving system wit ha latency of less than 40 ms for enhancing intelligibility of sound” (including speech, conversation and music) at the ear of the listener to achieve significantly Improved speech intelligibility (by increasing volume and reducing reverberation and background noise) for people who are hearing impaired or deaf
Note Ito entry: The term dear may be used for any level of hearing loss.
1.3.8
hearing device
personal device, used by people who are deaf or hearing impaired, for amplIfying and processing sound
Note 1 to entry: Examples of hearing devices include hearing aid. cochlear implant, bone anchored hearing aid (BAHA). brainstem implant, etc.
1.3.9
hearing impaired
describes people with a hearing loss who communicate predominantly orally and may or may not wear a hearing device
Note 1 to entry: An alternative to this term is hard o hcaring’
1.3.10
hearing loop cable
signal emitting component of a hearing loop system, consisting of a loop or coil of wire that generates the electromagnetic field
Note 1 to entry: A hearing loop system requires that the hearing loop cable layout he precisely designed and located, as well as matched to the hearing loop amplifier it Is connected to.
1.3.11
hearing loop system
wireless transmission system that emits an unmodulated audio electromagnetic signal, in which only the vertical component of the H field Is utilised (measured by picking up the field from a coil of conductive material would around a vertical core), and converts it to sound by use of hearing devices with a telecoil, or a loop listener consisting of an induction loop amplifier and a loop of wire
1.3.12
infrared system
wireless non-visible light lIne of sight transmission system that emits non-visible light waves from one or more infrared emitter(s) via a modulated infrared signal to an infrared receiver worn by the listener
1.3.13
latency
period of delay between when an audio signal is commenced (either by a person speaking, or commencement of a recording) and the time the receiver emits the audio signal
Note ito entry: Latency is usually measured in milliseconds.
Note 2 to entry: Latency greater than 40 milliseconds (ms) Is an impediment to clarity for people with hearling impairment.
1.3.14
level control
electronic system that maintains the audio signal to the user at a constant level to compensate for fluctuating signal input levels
Note 1 to entry: Level control is required as hearing loss affects a user’s ability to cope with variations in volume level.
Note 2 to entry: Level control may be built into a hearing loop amplifier, transmitter or emitter, or may be a supplied as a separate unit.
Note 3 to entry: A number of systems may be employed to achieve level control, including compression and automatic gain control, or a combination of both. This may be slow acting or fast acting.
1.3.IS
lipreading
process by which a lip reader observes the lip movements, facial expression and body language of the person speaking to gain information and understanding of the spoken word
1.3.16
loop listener
portable device that picks up the signal from a hearing loop system or neckloop and converts it to sound by use of a headset
1.3.17
modulated radio system
wireless system consisting of transmitter/s and receiver/s as per Clauses 2.2.4.1 and 2.2.4.2, and excluding infrared systems
1.3.18
monaural
provides the sound to only one ear
Note Ito entry: An example of a monaural device is an earpiece.
Note 2 to entry: For a person with hearing loss, having sound to both ears increases intelligibility.
1.3.19
phased dual array
hearing loop system consisting of a hearing loop amplifier, which has two amplifier modules and a 90° phase shifter, and two hearing loop cable layouts interlaced over each other
Note I to entry: Predominantly used for large areas, areas In which there are considerable losses In the electromagnetic field due to the presence of metal structures, and/or to prevent signals from a hearing loop system being heard outside the coverage area, such as ,idjacent coverage areas. Phased array loops can be specifically designed to reduce magnetic spill when required.