Source: https://www.access-board.gov/guidelines-and-standards/communications-and-it/142-508-standards/guide
Timestamp: 2016-05-26 12:32:08
Document Index: 494271004

Matched Legal Cases: ['§1194', '§1194', '§1194', '§1194', '§1194', 'art 68', 'art 68', '§1194', '§1194', '§ 12101', '§1194', '§1194']

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(NOTE: The relay services also have a newer “Speech to Speech” or STS service where they will re-voice speech for those who can speak, but whose speech is hard for many to understand.) This part of provision 1194.23(a) was necessary to ensure that a telephone system would not inadvertently prevent a telephone mouthpiece microphone from working when a TTY was being used with the telephone. For example, there have been instances where a cellular telephone has been designed so that its microphone is disabled while the cellular telephone’s headset jack was connected directly to a TTY. This prevented the TTY user from being able to utilize the VCO option. Once the TTY is disconnected from the cellular telephone, the cellular telephone mouthpiece returns to normal operation. A VCO mode in the cellular handset, which permits the microphone to be on while TTY is being received, is one way to meet this requirement. Another aspect of this provision is a requirement that the microphone be capable of being turned on or off. This enables a user to mute the microphone when receiving TTY tones to minimize introducing ambient noise into the line. The reason for keeping the line clear of unwanted noise is to minimize interference to TTY tones, which could result in garbled characters on the TTY display. Some manufacturers may consider developing a method for automating the switching process in the future. Design Guidance • Is my product affected by this provision? This provision applies to products that allow voice communications. For example, a fax machine with line-monitoring speaker (and no handset or microphone) is one-directional only and therefore, not covered, even though it emits speech, if a person answers the telephone on the other end of the fax call. However, a fax machine with a handset, enabling a two-way conversation, would be covered. As the provision states, this does not apply to products, which themselves, already have TTY functionality. For example, there are telephones on the market which represent a hybrid telephone and TTY designed as one unit. • Why is a non-acoustic connection important? A non-acoustic connection point is important because it allows the TTY user to achieve a lower data error rate than acoustic only connections. • What connectors do TTY’s most commonly use? The most common non-acoustic connection for wireline equipment is an analog PSTN RJ-11 jack. For cordless and analog wireless use, the non-acoustic connection commonly used is a 2.5 mm headset jack. For digital wireless, the most common would be a 2.5 mm headset jack that conforms to TIA TSB-121. Use of the 2.5 mm audio jack carries limitations. Telephones with audio jacks and no RJ-11 jack will not work with many popular office TTY models that only have RJ-11 jacks, including many of the currently available TTYs with printers and answering machines. This limitation is not much of a problem for TTYs that are compatible with wireless telephones; these TTYs are designed for mobility and do not have printers or answering machines, and can be well supported by the 2.5 mm jack. There has been a migration from analog to digital service. TTYs are analog-based devices and connect with RJ-11 jacks. TTYs and the wireline digital network can be damaged if TTYs are incorrectly connected to digital jacks. A TTY should not be plugged directly into a digital telephone network unless there is an analog jack or an analog converter available. Even if such a connection point is provided, there remains a possibility that the digital service may garble the TTY characters. • How can voice and TTY tones be intermixed?Under 508, the whole telephone system - including both telephone hardware and telephone service - must support the ability of users to communicate with text in one direction and speech in the other or to intermix speech and TTY tones in either of the directions (as might happen if a person’s speech is sometimes but not always understandable). Although it would sometimes be advantageous to allow communication in both directions to occur simultaneously without interfering with each other, this provision only requires the telephone system to support the ability for voice and TTY tones to alternate, not to be sent at the same time. Some software and modems allow a computer to function as a TTY and communicate directly over telephone lines. Section 508 does not require a computer to provide speakers and a microphone for use in telephone conversations. However, in cases where speakers and a microphone are available for telephone conversations, the system should conform to this provision by allowing speech and TTY tones to be intermixed. Vendors of such computer products should explain to Federal agencies how computers (when equipped with such assistive software and possibly a telephone) can be connected to the same line or jack to support VCO and HCO for both inbound and outbound calling. Provision Requirements
TTY Signal Protocols 508 Provision §1194.23(b) Telecommunications products which include voice communication functionality shall support all commonly used cross-manufacturer non-proprietary standard TTY signal protocols. Introduction & Background A two-way, real-time text-based telephone service for people with communication disabilities, based upon TTYs, was developed from teletype machines in the 1960s. The purpose of this provision is to ensure that TTY compatibility (with the signal, not just the connection point) is not overlooked. Specifically, this provision requires that mainstream telecommunications products be compatible with the traditional or standard TTY code of 45.5 baud Baudot. Design Guidance • Is my product affected by this provision? This provision applies to all telecommunications products that support 2-way voice communications. For example, a fax machine with a line monitoring speaker only (but no handset with microphone, and no speakerphone functionality) is only one-directional and therefore, not covered, even though it emits speech and sounds of the person at the other end of the call. However, a fax machine with handset and microphone, enabling a two-way conversation, would be covered. • What is a TTY and how does it work? A TTY is a text communication terminal that allows people with hearing or speech disabilities to use the telephone. TIA/EIA 825-A, “A Frequency Shift Keyed Modem For Use On The Public Switched Telephone Network” is the basic standard defining the Baudot TTY. TTYs (transmitting in 45.5 baud Baudot) that conform to TIA/EIA 825-A are silent when not transmitting.
Operation is "half duplex." Users of older model TTYs needed to take turns transmitting, and typically could not interrupt each other without causing errors in characters received. (However, users of some of the newer model TTYs that use a proprietary code can, in fact, interrupt one another without a loss of signal quality.)
When transmitting in 45.5 baud Baudot, there is no automatic mechanism that lets TTY users know when a character they have typed correctly has been received incorrectly. Each TTY character consists of a sequence of seven individual tones.
Voice mail, auto attendant, and interactive voice response systems should be usable by TTY callers, both to leave and retrieve messages, as well as to use the system features. This accessibility allows TTY users to navigate the systems independently without relying on a telecommunications relay service because the systems will directly send and receive TTY signals. Timing should be a consideration when designing the system to be “usable” as the provision requires. TTY users need sufficient time to read and respond prior to the system timing-out. Also, see 1194.23 (d).
It would be helpful if voice mail, auto attendant, and interactive voice response systems would either accept TTY Baudot tones or make it clear that the numbers that should be pressed are the ones on the telephone keypad (especially when they are talking to the user using Baudot). Read the IVR Accessibility Forum Disability Implications Matrix, which provides the industry with information about the barriers and advantages of IVR Systems for people with disabilities. See: http://www.atis.org/atis/ivr/ivrhom.htm. The information is presented in three ways. The application view is by product or industry, the interface view shows each step required by a user, and the disability view shows interface implications for specific disability categories. All views include links to definitions in the IVR Forum’s Accessibility Glossary. Note that some recommendations listed go beyond what the 508 Standard requires. Time Interval Alerts [3]508 Provision §1194.23(d) Voice mail, messaging, auto-attendant, and interactive voice response telecommunications systems that require a response from a user within a time interval, shall give an alert when the time interval is about to run out, and shall provide sufficient time for the user to indicate more time is required. Introduction & Background When a system requires a user to respond within a specified time, some people with mobility or dexterity disabilities or those using TTYs where they must read the messages may have difficulty completing actions before the timeout. TTY users may require extra time to interact with voice mail, messaging, auto attendant and interactive voice response systems. For these users, limits on response time can present a real frustration and barrier to using such systems. Another class of users that often have problems with voice mail, messaging, auto attendant, and interactive voice response systems are TTY users of the Telecommunications Relay Service (TRS). The TRS is a federally mandated system (Title IV of the ADA), which exists in all states, to primarily provide a translation function for TTY callers. This process is slower than audio calls. Voice mail, messaging, auto attendant and interactive voice response systems may timeout before the TTY caller can receive the system’s message in TTY code from the CA and type in their response. In addition, when multiple choices are offered, TTY callers may need to clarify the options with the communication assistant before understanding their choices. For TRS users, response time limits are a significant barrier. This provision is also very pertinent to users of a type of relay service known as Speech to Speech (STS). STS callers do not use TTYs. STS callers have speech disabilities and use specially trained STS CAs to repeat what they are saying so that the other party can understand them. Sometimes more than one attempt is necessary for the CA to understand what the person is saying before the CA can begin to pass the message on. Also, due to other physical disabilities, the STS user may also have difficulty entering DTMF tones in a timely fashion. Designers are reminded that this timeout provision applies to all users of voice mail, messaging, auto attendant, and interactive voice response systems, not just TTY users. For these reasons, this provision requires that the user be alerted when a time limit is approaching and that they be given the option for extending the time. Ideally, users will have the option of overriding the timed response and be able to take as much time as required to enter their responses. Alternately, users may continually be alerted to the timeout and extend it as long as they need, until they can effectively respond to the system as long as user’s input is not erased each time a time extension it evoked and granted. Design Guidance • Is my product affected by this provision? This provision applies to all voice mail, messaging, auto attendant, and interactive voice response systems that require a user response within a specified time interval. • After alerting the user, how much time should be allowed? It is desirable for an alert to be made 5 seconds before a response period times out, but a duration is not specified in the 508 standards. The user should be given the option of indicating that additional time is needed to complete their response. If additional time is requested, the information entered to the point of the warning announcement should be preserved and the user should be allowed to continue inputting information from that point. Provision Requirements
Caller ID and Similar Functions508 Provision §1194.23(e) Where provided, caller identification and similar telecommunications functions shall also be available for users of TTYs, and for users who cannot see displays. Introduction & Background This provision addresses two different problems: 1.) the accessibility of information which is normally presented on a display to users who cannot see displays; and 2.) the availability of information to TTY users that is usually provided on some landline digital telephone systems. The second problem is an issue when TTY users do not use landline digital telephone systems, due to the potential for the system to corrupt TTY signals. The kind of information pertinent to this provision is information about telecommunication functions. Many current office and wireless telephones have displays that provide information such as Caller ID or indication of new voice mail messages to the user. Caller ID, also known as ANI or automatic number identification, can display both the name and number of a caller. Someone with a visual disability might not be able to see this information and therefore would not experience “comparable access” to the telephone system, unless that information was provided in another format. TTY users may have special problems with obtaining this telecommunication information, which is commonly transmitted and displayed via digital trunks or lines on landline telephone systems. TTY users have often been limited to the use of an analog line, which provided a connection point, supported ring signaling assistive technology, and avoided garbling of TTY through the digital telecommunications system. [See provisions 1194.23 (b) and (j).] However, this analog bypass arrangement is not considered a method of 508-compliance because TTY users miss the functionality and additional information provided through a digital telephone system. Therefore, this problem of TTY user information access needs to be addressed by design engineers in order for a telephone system to conform to the 508 standards. Federal procurement officers should know that this is not a problem with all digital telephone systems. Design Guidance• Is my product and/or service affected by this provision? Products and/or services that deliver, support, or provide special information functions, such as Caller ID, are covered by this provision. Automatic location identification (ALI), which displays a caller’s address, is also covered, but is less commonly used. • How is accessibility to functionality information provided? Information about telecommunications functions can be made available visually, on a display, and audibly. One method of meeting the provision through auditory access is commonly known as “talking Caller ID”. Another way of meeting the provision is by providing compatibility with assistive technology. For example, where telephones and computers are integrated, software can enable telecommunications information to be displayed via the computer screen. This allows users to read it by using assistive technology, such as refreshable Braille displays or screen readers. To elaborate, special functions, such as Caller ID, are often only available in digital form. Many landline office telecommunications devices support the TAPI interface, which is a standard protocol allowing exchange of information between telecommunications equipment and information technology equipment, (i.e., telephones and computers). There is a newer version of the TAPI protocol, known as the Extended TAPI protocol. Through the Extended TAPI interface, the Caller ID number can be transmitted and viewed on a personal computer. Software is available that will translate the information from the Extended TAPI protocol to a form usable by assistive software. If the software is left running in the background, the user may access (audibly or tactilely using assistive technology) the telephone number of an incoming call in the same timeframe as someone looking at the telephone LCD display. Thus, for situations where telephones and computers are integrated, the functionality of the computer could be used to meet this provision. This is an example of “equivalent facilitation”. A TAPI interface on a telephone not connected to a computer would probably not satisfy this provision unless the telephone had voice output of the visual information on its display. Provision Requirements
Volume Control508 Provision §1194.23(f) For transmitted voice signals, telecommunications products shall provide a gain adjustable up to a minimum of 20 dB. For incremental volume control, at least one intermediate step of 12 dB of gain shall be provided. Introduction & Background People with hearing loss generally require additional volume to hear effectively. A user may not be able to understand speech at nominal volume levels. This provision enables people who are hard of hearing to increase their telephone volume gain in order to maximize their residual hearing. Many people with hearing loss are more sensitive to noise and less able to recognize words in the presence of noise than individuals with normal hearing. Therefore, increased volume assists these users in achieving a volume level and speech-to-noise ratio sufficient for their needs. Design Guidance• Is my product affected by this provision? This provision applies to all telecommunications products that transmit a two-way voice signal. Products that only provide one-way communications, such as speakers that give operating instructions to the user, are not covered by this provision. • dB is a relative term, what is the reference quantity? The term dB is a logarithmic unit used to describe a ratio. When used with SPL (e.g., 65 db SPL) it expresses an absolute measure of sound pressure level (against no sound). Most telecommunications standards now define gain in terms of Receive Output Loudness Rating, not Sound Pressure Level. • What gain level is required? This provision requires products to be equipped with volume control that provides an This provision requires products to be equipped with volume control that provides amplification adjustable to a gain of at least 20 dB above the default volume.. If a volume adjustment is provided that allows a user to set the gain anywhere from 0 to the minimum requirement of 20 dB gain above default, then there is no need to specify an intermediate step of 12 dB. If a stepped volume control is provided, one of the intermediate levels must provide 12 dB of gain above default. Some telephones are set with a higher default than others. These telephones are not given “credit” for providing a high default setting and must still provide 20 dB of gain above their default setting in order to conform to this provision. Some phones may allow the user to reset the default volume. In these cases the default is that setting that the manufacturer normally uses for the telephones as sales time. Provision Requirements
Automatic Volume Reset508 Provision §1194.23(g)If the telecommunications product allows a user to adjust the receive volume, a function shall be provided to automatically reset the volume to the default level after every use.Introduction & Background This provision applies to all telecommunications products that allow a user to adjust the volume. It was adopted from the ADA Accessibility Guidelines, where it applies to public telephones used by many people. It also has roots in the FCC's Part 68 rule, which has required an automatic reset when a landline telephone is hung-up after a call in which the volume exceeds 18 dB gain. The ability to override the reset is helpful to people with hearing loss who find it inconvenient to adjust their preferred amplification level for every call, especially on incoming calls. In other words, the telephone will be loud every time they answer it. In December 2000, when the Access Board published the Section 508 standards in the Federal Register, it wrote in the preamble that allowing override of the reset function would require a waiver from the FCC. However, since that time, the FCC did, in fact, issue such a waiver in March 2001. See the Public Notice at: http://ftp.fcc.gov/cgb/dro/vc_notic.doc. And also see the Memorandum Opinion and Order at: http://ftp.fcc.gov/Bureaus/Common_Carrier/Orders/2001/da010578.doc. Therefore, on this basis, the Access Board believes that a telecommunications product can conform to the Section 508 standards if it has either a fixed automatic reset function or an optional override of that switch. This interpretation does not change the 508 standards, which still require an automatic reset function to be provided. It simply acknowledges that a manufacturer (via the FCC waiver) has an option to enable users the ability to override the volume reset function, if the manufacturer wishes to design a telephone that way. It is important to draw attention to the word “function” in this provision. There is a difference between requiring an automatic reset and requiring a function to automatically reset. Requiring a reset after each call is a fixed action, whereas including reset as an option provides flexibility to turn that function switch on or off. This 508 provision requires a automatic reset function, which is a broader requirement because it allows an override. Provision 1194.23(g) does not preclude an override function. For safety reasons, however, it is recommended that the reset function on telephones normally used by people who are hard of hearing be deactivated only when those telephones will not be shared with other people. The FCC granted its waiver on the basis that telephone manufacturers meet the following conditions:(1) The volume reset override switch shall be labeled as such and located on the telephone in such a way as to not be accessible to accidental engagement; (2) A bright indicator light shall be prominently displayed on the front of the telephone and shall light up when the override is engaged and the telephone is placed in an off-hook condition; (3) Next to the light shall be a warning that the amplification is at a high level; (4) A caution on the use of the volume reset override switch shall be included in the users’ manual; and (5) The telephone shall include a warning printed in Braille that can be securely attached to the back of the handset, or, if the telephone has only a headset, above the dial buttons, to indicate that a high volume setting may be engaged.
Design Guidance• Is my product affected by this provision? This provision applies to all telecommunications products that allow the user to adjust the volume. It has roots in the FCC's Part 68 rule, which requires an automatic reset when a landline telephone is hung up if the volume exceeds 18 dB gain. This reset provision is a safety feature for handsets implemented by the FCC, and does not apply when a product is in hands-free [speakerphone] mode. Provision RequirementsIf a telecommunications product allows a user to adjust the receive volume, a function shall be provided to automatically reset the volume to the default level after every use. Recommended Practices
Minimized Interference508 Provision §1194.23(i)Interference to hearing technologies (including hearing aids, cochlear implants, and assistive listening devices) shall be reduced to the lowes Arial">t possible level that allows a user of hearing technologies to utilize the telecommunications product.Introduction & Background The purpose of this provision is to help ensure that users of hearing technologies are not prevented from using telecommunications products due to interference. The term “hearing technologies” includes hearing aids, cochlear implants, assistive listening devices, and other types of hearing technologies. These technologies pick up radio frequency (RF) signals, which are radiated from digital wireless/cellular telephones’ antennas using energy pulses that the hearing instrument circuitry picks up and demodulates as audible interference. In addition, magnetic fields generated by handset components, such as battery leads, may cause noise when hearing technology wearers are using the telecoil to couple inductively to the handset. Many hearing technology wearers, therefore, hear significant buzzing or pounding sounds that may completely mask the speech of a call and make the wireless digital telephone unusable for voice conversations. Some hearing technologies are more immune to interference than others. Some digital wireless/cellular telecommunications transmission technologies cause more annoying interference than others. Compatibility ideally means that the hearing instrument and telecommunications product function well as a system. That may require meeting both the magnetic coupling requirement [provision (h)] as well as this minimized interference requirement [provision (i)]. Previously in the 1980s when the Federal Communications Commission (FCC) referred to hearing aid compatibility (HAC), it meant only magnetic coupling [provision (h)]. That was written during a period in time when wireless/cellular telephones were analog and most of those telephones did not cause interference. However, in keeping with the new challenges posed by digital technologies, the FCC recently redefined HAC for digital wireless/cellular telephones to mean a combination of both magnetic coupling and minimized interference. This portion of technical assistance will address only the minimized interference issue. Compatibility, in this limited context, refers to the coordination of hearing technologies with RF immunity and wireless devices that minimize RF emissions. The hearing technology industry and cellular telephone industry recently completed a standard, ANSI C63.19-2001, which provides specific tests and target parameters for hearing aids and wireless/cellular telephones. This measurement methodology was developed to facilitate improved interoperability between hearing aids and some wireless/cellular telephones through the implementation of the standard by both industries. Design Guidance• Is my product affected by this provision? This requirement is applicable to all products that provide a voice telecommunications function. • What guidance can be used in conforming to this provision? In August 2003, the Federal Communications Commission (FCC) issued a ruling directing wireless/cellular telephone manufacturers and wireless/cellular service providers to take steps to reduce the amount of interference caused by wireless/cellular telephone handsets. The FCC’s Report and Order is intended to ensure that redesigned compatible cellular telephone handsets will be widely available and hearing aid immunity will continue to improve. Specifically, it requires a percentage of wireless/cellular digital telephones with reduced interference within 3 years. To view this FCC Report and Order, see: http://ftp.fcc.gov/cgb/consumerfacts/accessiblewireless.html. ANSI C63.19-2001 provides procedures to measure electromagnetic emissions produced by wireless/cellular handsets. The standard provides two summary test results, one for radio frequency emissions that create a buzzing noise in hearing aids primarily when they are in the microphone (default) setting, and one for compatibility with the hearing aid's telecoil. For each of these results, there are four levels defined, with 4 being the best (lowes Arial">t emission) category. The FCC has set a minimum of category 3 for telephones that are to be considered (and labeled) as compatible with hearing aids. (The FCC rule begins to go into effect in 2005.) The FCC's rule thus includes consideration of interference when determining whether a wireless/cellular telephone is "hearing aid compatible. Code Division Multiple Access (CDMA) based technologies generally cause less bothersome interference in hearing aids than do Global System for Mobile Communications (GSM) technologies. In light of the FCC ruling, the Federal Interagency Committee on Disability Research (ICDR) held a timely “Summit on Interference to Hearing Technologies” in September 2003. Participants included representatives from the digital wireless telephone and hearing technologies industries, disability organizations, research centers, and Federal agencies, such as the FCC and the Food and Drug Administration (FDA). Presentations were made on laws that address hearing aid compatibility, new technological developments, and telephone designs that reduce interference, and the results of laboratory and consumer testing. Proceedings from the conference will be posted on ICDR’s website at www.icdr.us. Provision Requirements
Controls & Keys[4]508 Provision §1194.23(k) Products which have mechanically operated controls or keys, shall comply with the following:(1) Controls and keys shall be tactilely discernible without activating the controls or keys. (2) Controls and keys shall be operable with one hand and shall not require tight grasping, pinching, or twisting of the wrist. The force required to activate controls and keys shall be 5 lbs. (22.2 N) maximum. (3) If key repeat is supported, the delay before repeat shall be adjustable to at least 2 seconds. Key repeat rate shall be adjustable to 2 seconds per character. (4) The status of all locking or toggle controls or keys shall be visually discernible, and discernible either through touch or sound.
Audio indication of a toggle status, instead of being a continuous signal, could be sufficiently long to alert the user to the position of the toggle switch. III. REFERENCES ANSI C63.19-2001, “American National Standard for Methods of Measurement of Compatibility between Wireless Communications Devices and Hearing Aids”. EIA RS-504-1983, "Magnetic Field Intensity Criteria for Telephone Compatibility with Hearing Aids. TIA/EIA 825-A (2003), “A Frequency Shift Keyed Modem For Use On The Public Switched Telephone Network” TIA TSB-121, “2.5 mm Audio Interface For Mobile Wireless Handsets - Text Telephones (TTY)”
[1] 36 CFR 1194, Electronic and Information Technology Accessibility Standards, Architectural and Transportation Barriers Compliance Board, Published in the Federal Register on December 21, 2000.[2] Americans with Disabilities Act, 42 U.S.C. §§ 12101 et seq., (ADA). [3] The 508 provisions, §1194.22(p) and §1194.25(b), are identical or have substantial overlap with this provision. The guidance provided for those sections may provide additional insight on this requirement.