This appendix contains materials of an advisory nature and provides additional information that should help the reader to understand the minimum requirements of the guidelines or to design buildings or facilities for greater accessibility. The paragraph numbers correspond to the sections or paragraphs of the guideline to which the material relates and are therefore not consecutive (for example, A4.2.1 contains additional information relevant to 4.2.1). Sections of the guidelines for which additional material appears in this appendix have been indicated by an asterisk. Nothing in this appendix shall in any way obviate any obligation to comply with the requirements of the guidelines itself.
A4.33.2 Size of Wheelchair Locations. Spaces large enough for two wheelchairs allow people who are coming to a performance together to sit together.
A4.33.3 Placement of Wheelchair Locations. The location of wheelchair areas can be planned so that a variety of positions within the seating area are provided. This will allow choice in viewing and price categories.
Building/life safety codes set minimum distances between rows of fixed seats with consideration of the number of seats in a row, the exit aisle width and arrangement, and the location of exit doors. "Continental" seating, with a greater number of seats per row and a commensurate increase in row spacing and exit doors, facilitates emergency egress for all people and increases ease of access to mid-row seats especially for people who walk with difficulty. Consideration of this positive attribute of "continental" seating should be included along with all other factors in the design of fixed seating areas.
Removable armrests are recommended on fixed companion seats provided in assembly areas in amusement facilities. This provides the option for an individual using a wheelchair or other mobility device to transfer into a seat where motion and other effects may be provided as part of the amusement experience.
A4.33.6 Placement of Listening Systems. A distance of 50 ft (15 m) allows a person to distinguish performers' facial expressions.
A4.33.7 Types of Listening Systems. An assistive listening system appropriate for an assembly area for a group of persons or where the specific individuals are not known in advance, such as a playhouse, lecture hall or movie theater, may be different from the system appropriate for a particular individual provided as an auxiliary aid or as part of a reasonable accommodation. The appropriate device for an individual is the type that individual can use, whereas the appropriate system for an assembly area will necessarily be geared toward the "average" or aggregate needs of various individuals. A listening system that can be used from any seat in a seating area is the most flexible way to meet this specification. Earphone jacks with variable volume controls can benefit only people who have slight hearing loss and do not help people who use hearing aids. At the present time, magnetic induction loops are the most feasible type of listening system for people who use hearing aids equipped with "T- coils," but people without hearing aids or those with hearing aids not equipped with inductive pick-ups cannot use them without special receivers. Radio frequency systems can be extremely effective and inexpensive. People without hearing aids can use them, but people with hearing aids need a special receiver to use them as they are presently designed. If hearing aids had a jack to allow a by-pass of microphones, then radio frequency systems would be suitable for people with and without hearing aids. The Department of Justice's regulations implementing titles II and III of the ADA require public accommodations to provide appropriate auxiliary aids and services to ensure effective communication. See 28 C.F.R. 35.160, 28 C.F.R. 35.164, and 28 C.F.R. 36.303. Where assistive listening systems are used to provide effective communication, the Department of Justice considers it essential that a portion of receivers be compatible with hearing aids.
Some listening systems may be subject to interference from other equipment and feedback from hearing aids of people who are using the systems. Such interference can be controlled by careful engineering design that anticipates feedback sources in the surrounding area.
Table A2, shows some of the advantages and disadvantages of different types of assistive listening systems. In addition, the Access Board has published a pamphlet on Assistive Listening Systems which lists demonstration centers across the country where technical assistance can be obtained in selecting and installing appropriate systems. The state of New York has also adopted a detailed technical specification which may be useful.
| COMPARISON OF LARGE AREA ASSISTIVE LISTENING SYSTEMS | |||
| System Description | Advantages | Disadvantages | Typical Applications |
| FM BROADCAST (40 frequencies available on narrow band transmission systems. Ten frequencies available on wideband transmission systems.) Transmitters: FM base station or personal transmitter broadcasts signal to listening area. Receiver: Pocket size with: a)earphone(s), or |
Highly portable when used
with body-worn, personal transmitter.
Easy to install. May be used separately or integrated with existing PA-systems. Multiple frequencies allow for use by different groups within same area (e.g., multi- language translation). |
Signal spill-over to adjacent
rooms/ listening areas (can prevent interference by using different transmission
frequencies for each room/listening area). Choose infrared if privacy
is essential.
Receivers required for everyone. Requires administration and maintenance of receivers. Susceptible to electrical interference when used with induction neck-loop/silhouette (Provision of DAI audio shoes and cords is impractical for public applications). Some systems more susceptible to radio wave interference and signal drift than others |
Service counters
Outdoor guided tours Tour busses Meeting rooms Conference rooms Auditoriums Classrooms Courtrooms Churches and Temples Theaters Museums Theme parks Arenas Sport stadiums Retirement/nursing homes Hospitals |
| INFRARED LIGHT Transmitter: Amplifier drives emitter panel(s) covering listening area. Receivers: Under-chin or Pendant type receiver with: a) headset, or b) earphone(s), or c) induction neck-loop or silhouette coil coupling to personal hearing aid equipped with telecoil, or d) direct audio input (DAI) to personal hearing aid. |
Unlike induction or FM
transmission, IR transmission does not travel through walls or other
solid surfaces.
Insures confidentiality. Infrared receivers compatible with most infrared emitters. May be used separately or integrated with existing PA-systems. Can be used for multi- language translation (must use special multi-frequency receivers). |
Receivers required for
everyone. Requires administration and maintenance of receivers.
Ineffective in direct sunlight. Careful installation required to insure entire listening area will receive IR signal. Susceptible to electrical interference when used with induction neckloop/silhouette (Provision of DAI audio shoes and cords is impractical for public applications). Lifetime of emitters varies with company. Historical buildings may pose installation problems. |
Indoor service counters
Meetings requiring confidentiality Meeting rooms Conference rooms Auditoriums Classrooms Courtrooms Churches and Temples Theaters Museums Arenas (indoors only) Sport stadiums (indoors only) Retirement/nursing homes Hospitals |
| CONVENTIONAL INDUCTION
LOOP Transmitter: Amplifier drives an induction loop that surrounds listening area. Receivers: a)Personal hearing aid with telecoil. b)Pocket size induction receiver with earphone or headset. c)Self-contained wand. d)Telecoil inside plastic chassis which looks like a BTE, ITE, or canal hearing aid. |
Requires little, or no
administration of receivers, if most people have telecoil-equipped hearing
aids. Induction receivers must be used where hearing aids in use are
not equipped with telecoils.
Induction receivers are compatible with all loop systems. Unobtrusive with telecoil hearing aid. May be used separately or integrated with existing PA-systems. Portable systems are available for use with small groups of listeners. These portable systems can be stored in a carrying case and set up temporarily, as needed. |
Signal spill-over to adjacent
rooms.
Susceptible to electrical interference. Limited portability unless areas are pre- looped or small, portable system is used (see advantages). Requires installation of loop wire. Installation may be difficult in pre- existing buildings. Skilled installation essential in historical buildings (and may not be permitted at all). If listener does not have telecoil-equipped hearing aid then requires administration and maintenance of receivers. |
Service counters
Ports of transportation Public transportation vehicles Tour busses Meeting rooms Conference rooms Auditoriums Classrooms Courtrooms Churches and Temples Theaters Museums Theme parks Arenas Sport stadiums Retirement/nursing homes Hospitals |
| 3-D LOOP SYSTEM
Transmitter: Amplifier drives a 3-D mat that is placed under the carpet of the listening area. Receivers: a) Personal hearing aid with telecoil. b) Pocket size induction receiver with earphone or head-set. c) Self-contained wand. d) Telecoil inside plastic chassis which looks like a BTE, ITE, or canal hearing aid. |
Requires little, or no
administration of receivers, provided most listeners have telecoil-equipped
hearing aids.
Induction receivers are compatible with all loops systems. May be used separately or integrated with existing PA-systems. Three-dimensional reception of loop signal regardless of telecoil position. Reduced signal spillover allows adjacent rooms to be looped without signal interference. 3-D loop mats must be separated by 6 feet to avoid signal spillover. |
Limited portability (areas
may be pre-3-D Loop matted to facilitate portability).
Requires installation of 3-D Loop mats. Instal- lation may be difficult in pre-existing build- ings. Skilled installa- tion essential in historical buildings (and may not be permitted at all). If listener does not have telecoil-equipped hearing aid then requires administra- tion and maintenance of receivers. Susceptible to electrical interference. |
Service counters
Ports of Transportation Meeting rooms Conference rooms Auditoriums Classrooms Courtrooms Museums Theme Parks Retirement/nursing homes Meetings requiring confidentiality Hospitals |
| Modified
from a chart published by Centrum Sound, Cupertino, California Cynthia L. Compton, Assistive Devices Center Department of Audiology and Speech-Language Pathology Gallaudet University, Washington, DC |
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