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November 2003

Assistive Listening Systems (ALS) Help You Communicate Effectively

No one wants to miss out on what science centers and museums offer, but visitors with a hearing loss often do. Science centers and museums cannot afford to lose this significant population who can do everything else but hear. Install permanent or use portable assistive listening systems (ALS), provide receivers and headsets, and you turn an obligation into an asset.

Harold poses in outdoor plaza of the Chabot Space and Science Center, Oakland, California.

Meet Harold. Like many of the 28 million people in the United States who are hard of hearing, Harold wants to sit back and enjoy a planetarium show, watch a large-format film, learn from a demo or lecture, join a tour, and take his grandchild to a family program. Assistive listening systems make that a possibility. Open slide show.

Turn your obligation into an asset. If you have an assembly area, lecture hall, theater or meeting room built or altered since 1992 with fixed seats and an audio-amplification system, or an assembly area with or without an audio-amplification system that seats 50 or more people, you are legally obligated to have a permanently installed assistive listening system. You need to provide receivers to serve at least 4% of the seats (but no fewer than two) and you need to have signage that informs patrons that an assistive listening system is available. (See ADA Standard for Accessible Design 4.1.3 (19) (b)). Whether or not your institution has built or renovated an assembly area since 1992, the ADA requires you to ensure "equally effective" communication with people with disabilities (ADA 28 CFR 36.303); an ALS is one option.

Permanently installed assistive listening systems (ALS) are made up of a transmitter, microphone, a mixer/amplifer, a receiver, and headset. Portable assistive listening systems are made up of a body pack radio transmitter with microphone and a receiver with headset or other listening accessory.

The chart below describes three main assistive listening systems. A description of the various receivers and listening accessories follows the chart.

Listener wears silhouette listening accessory connected to a receiver to hear sounds transmitted via an FM system.Frequency Moderated or FM systems are wireless systems that transmit sound via radio waves. The speaker uses a microphone connected to a small transmitter/receiver worn or carried by the user. FM systems come in different sizes so choose a system according to area size. A FM system is usually a good choice for classroom/meeting use, gallery tours, and demos. A FM system works well both indoors and outdoors. Some systems are portable, and some provide more than one channel. Also, this system can be connected to your existing PA system. Use receivers with multiple channels if there is more than one FM system used in the building because sound can spill over from one space to another. All users will need receivers. In general, placing the transmitter or the antenna facing the audience usually enhances sound quality.

Listener wears silhouette listening accessory connected to a receiver to hear sounds transmitted via an infrared system.Infrared systems transmit sounds by invisible light beams. To be effective, receivers used by patrons must be within direct line of sight of the light beam coming from the transmitter. There is no spill over to other rooms but all users need receivers. These systems cannot be used outdoors because of interference from sunlight. Inside, bright, incandescent light may also cause interference. Infrared systems work well for small group meetings as well as in auditoriums. Be sure to have enough emitters and position their locations carefully to avoid dead spots. Similar to listening stations in your gift shop where customers review CDs, exhibits designed with audio output jacks with volume control allow visitors to plug in a headset, neckloop, or patch cord and hear the narration.

Listener wears silhouette listening device connected to a receiver to hear sounds transmitted within an induction loop system.Induction loop systems broadcast an electronic current within a specific area. A microphone or patch cord feeds sound from the source into an amplifier. The signal is then fed into a loop of wire that encircles the space. This wire, which may be permanently installed (above ceiling panels, under carpeting, behind baseboards), blankets the surrounding area with EMFs (Electromagnetic Fields). Installation may be difficult in pre-existing buildings. This system is susceptible to electrical interference. Persons with "T" coils in their hearing aids or cochlear implants will not need receivers if they are within the looped area. ("T" coils are also known as telecoils and telephone switches; they were originally included in hearing aids to improve telephone communication.)

Consultant shows how silhouette listening accessory fits behind the ear and connects to a portable receiver.Receivers and listening accessories. Users "plug into the system" by way of a receiver and a headset. There are many types to choose from. For example, receivers come in mono or stereo and headsets come with the receiver built-in or with different plug-in ear pieces. One or two earpieces are available as are ear buds, headphones, neckloops, and silhouettes. Neckloops go around the neck while the silhouette fits behind the ear. Neckloops and silhouettes are used by persons having a "T" coil in their hearing aid. Patrons with cochlear implants will likely bring a patchcord to connect from their processor to the receiver you provide (your having the right patchcord to this very customized piece of equipment is highly unlikely; as a result, ask patrons to use their own patchcords).

Microphones. Selection and then location of microphones are key variables to consider and test.

Involve people with hearing loss to test the equipment you are considering for purchase because what may sound just fine for you may not be adequate for people with hearing loss. At the same time you are involving groups and educated consumers in testing equipment, ask their suggestions about how and where to market this new visitor service most effectively.

Installation. If system components are made by different manufacturers, make sure they are compatible. In general, to insure the best set up, the installer must consider not only the space, but the kinds of programs in the space, and the needs of audience members with hearing loss. The installer should also consider interference and overlap from other systems and sounds. Again, for best results, test variations with potential users.

How will you make your ALDs available? Visitors with hearing loss often do not ask for information because they may have trouble hearing the answer. Be sure that the accessibility symbol for assistive listening devices is highly visible, both at your main information desk as well as where devices are distributed. Don't let the signs stray: mark the spot with tape or paint. Add the specific system frequency for visitors who have their own receivers and may want to use them instead of yours. If this information is not posted on a sign, be sure staff and volunteers know it. If neckloops, silhouettes, and written scripts are available, note this information as well.

Assistive listening system icon.Many institutions have a desk or counter where staff or volunteers distribute receivers and listening accessories. Some distribution places are permanent, some portable. Permanence makes for consistency and can allow for storage, if drawers have been built in. The main point is to be near the venues where patrons need them.

As for loaning receivers, headsets, etc., to visitors, museums handle this differently: some request an ID; others ask for name and telephone number; and some do neither. Like other accommodations (e.g., large print programs), institutions cannot charge for something a visitor with a disability needs to fully participate.

Ongoing training helps insure that staff and volunteers will be able to answer patrons' questions, show them how receivers work, and test and maintain equipment. Keep a laminated copy of answers to frequently asked questions at the counter or desk where receivers and listening accessories are distributed. Schedule staff and volunteers to be on hand during intermission(s) should a faulty device need trouble-shooting or replacing. And develop a form so that when devices are collected, staff and volunteers can report equipment in need of repair or replacement.

Maintenance. Users expect, and rightly so, that the equipment you give them will be in working order. Schedules for checking equipment and charging rechargeable batteries will help to insure good customer service. Storage is another issue to solve as are any hygienic measures you want to employ after use (e.g., sanitizing earpieces and cushions or replacing them).

Open captioning icon. Other ways to make text available to people with hearing loss. Many people who are hard of hearing as well as those who are deaf benefit from captioning. Pre-recorded media can be captioned in advance and displayed as OPEN CAPTIONING (OC) or CLOSED CAPTIONING Closed captioning icon.(CC). Both provide a continuous written narration across the screen that includes not only text but sounds (e.g., siren). OC cannot be turned-off while CC remains hidden until activation--usually by a button marked Audio Text.

Increasingly, large-format theaters and planetariums are installing a captioning system for films and programs. An example of a closed captioned system is Rear Window; it was developed by the National Center for Accessible Media at WGBH. It is unobtrusive. Patrons adjust a portable Lucite panel to read the captions running off a screen installed behind them. Having Rear Window or another captioning system in place is the first step; lobbying distributors to routinely provide captioning with their films is another. It's in everyone's best interest.

As speaker talks, stenographer types; text is displayed in real time on a monitor.When narration is needed in real time as in a meeting or lecture, computer-aided real-time reporting (CART) is a good option. As a trained stenographer types, text is displayed on a monitor or screen. CART provides not only captioning in real time but an unedited transcript of the proceedings.

Although scripts are difficult to read in a darkened theater, providing scripts for patrons before, during, and after a show or presentation, will be appreciated. (Choose a sans serif font, 16 point.)

Tips for speakers. Everyone hears better when speakers follow these simple rules:
  • Face the audience so they can use visual cues to aid their understanding;
  • Speak into the microphone;
  • Wear a lavaliere mike if moving about;
  • Ask audience members to speak one at a time;
  • Repeat questions if a microphone is not available.
Market, market, market. Market internally and externally. Internally, use staff meetings to demonstrate how your system(s) work and to report users' responses. Externally, put information about the availability of this service in all the places where you currently advertise your programs and events (e.g., ads, your newsletters, school brochures, and web site); then look for more. Where in your community do people with hearing loss look for information about programs and events? Make some calls to find the newsletters and e-mail lists where you can routinely send your news and announcements. Because a large proportion of older adults have a hearing loss, be sure to consult your local and state departments for senior and adult services.

Assistive listening system icon.Use the ALS accessibility icon in all your print materials and on your web site to draw readers' attention to its availability. Provide your e-mail address and phone number(s), including the TTY number, if you have one. Depending on whether your TTY is a separate number or not, choose one of the following formats: 508-347-3362 (voice) or 508-347-5383 (TTY); or 617-695-1225 V/TTY.

Read Others' Experiences for more ideas and please Share Your Own.

      For more information
  • Review guidelines for assembly areas and effective communication in the ADA Standards for Accessible Design, in your state code, and in your local code, and follow the most stringent. Make a copy of Bulletin #8C: Assistive Listening Systems for Providers; it covers the basics with recommendations for what to look for to maximize benefits.
  • There are many organizations and agencies that work for and with people who have hearing loss who can assist you in thinking through your choices; one or more are likely in your community. An example is Self Help for Hard of Hearing People, Inc. (SHHH). Another way to begin is to call your state commission on deafness and hard of hearing. This list for the U.S. is on the web site for the Alexander Graham Bell Association for the Deaf and Hard of Hearing.
  • A list of manufacturers and vendors and a discussion of common problems are just two of the topics that make Assistive Listening Devices for People with Hearing Loss an excellent resource. It was produced by Betty Siegel, Manager of Disability Services,The Kennedy Center. Contact her for a PDF copy:
  • "Demystifying Assistive Listening Devices" written by Cheryl D. Davis is on the web site of the Regional Resource Center on Deafness based in Western Oregon University. Topics covered include Communication Tips, T-coils & Couplers & Mics! Oh My!, as well as information on the advantages and disadvantages of each system.
  • Disability access symbols can be found on the web pages of the Graphic Artists Guild.
  • The section of the ASTC web cite called Accessible Practices includes links to information and resources regarding assistive listening systems, captioning, audio description, and sign language interpretation. They are under the heading Best Practices. The web pages of The National Center for Accessible Media (NCAM) will give you information on Rear Window and MoPix, a system that combines captioning, assistive listening devices, and audio description.

National Science Foundation LogoAccessible Practices EXCHANGE is supported by the National Science Foundation under Grants No. ESI-9814917 and HRD 9906095. Opinions or recommendations expressed in this material are those of the author and presenters and not necessarily those of the National Science Foundation.
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ASTC is not responsible for the enforcement of the Americans with Disabilities Act (ADA) or Section 504 of the Rehabilitation Act of 1973. The information presented here is intended solely as informal guidance, and is neither a determination of your legal rights or responsibilities under the ADA, nor binding on any agency with enforcement responsibility under the ADA. This web site is not intended to offer legal, architectural, engineering, or similar professional advice. You should refer specific questions to an attorney, and/or national, state, and local ADA authorities.
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