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- CARD-READING PUBLIC STATIONS REQUIREMENTS
- Bell Communications Research, Inc.
-
- 1. This document describes generic requirements for card-reading public
- telephone stations. These stations will be deployed by a Bell Operating
- Company (BOC) primarily to provide customers having magnetic-stripe
- cards with easier access to both BOC and inter-LATA carrier (IC)
- facilities.
-
- A BOC Card-Reading Public Station (alternatively referred to as
- "station") is intended to work similarly to a current Charge-a-Call
- station with features added to read a magnetic-stripe card and
- conveniently select an IC. The BOCs expect to issue Calling Cards for
- use in making intra-LATA toll and local calls over the BOC networks, and
- inter-LATA calls over any carrier capable of accepting a Calling Card
- number. Similarly, calls billed via Commercial Credit Cards (CCC) would
- be possible if the involved BOC or IC were able to accept them.
-
- 1.1 Outline of Document
-
- Section 1.2 describes the scope of the document. The general operation
- of the station is described in section 1.3.
-
- Section 2 specifies the requirements for a card-reading public telephone
- station. Section 2.1 sets the requirements for card presentation,
- including how and when the card should be presented, and what the
- station should do if the presentation of the card differs from that
- required.
-
- Section 2.2 specifies the requirements for signaling by the customer.
- This includes acceptable dialed destination numbers, methods of
- selection of the IC, and anti-fraud features of the station.
-
- Section 2.3 specifies the requirements on how the station will interface
- with the end (local) office. The features of the line and electrical
- characteristics are described.
-
- Section 2.4 describes the interface between the station and the IC or a
- processor. This includes description of the access environment and what
- the station should do to help set up calls.
-
- Section 2.5 specifies the physical characteristics of the station.
- Section 3 contains requirements pertaining to the support that the
- supplier should provide for these stations.
-
- 1.2 Scope of Document
-
- This document provides functional requirements for a card-reading,
- non-coin public station. The requirements are intended to describe what
- the station does in its various interactions with the customer, the
- local office, and the carrier of choice or an associated processor. The
- requirements also describe the physical environment in which the station
- operates. This document is not intended to dictate how given functions
- are specifically realized.
-
- Card reading transactions described here are limited to magnetic-stripe
- card technology and cover only those actions required to set up and
- properly bill a call. These requirements are generally limited to the
- station itself. Actions by other facilities to provide public calling
- via credit cards are included only insofar as they relate to pertinent
- station functions.
-
- This document contains requirements primarily concerning public
- stations, card reading, and carrier selection. The station should also
- meet requirements specified by the FCC Rules regarding registration of
- telephone sets (Part 68), FCC Rules regarding radiated emissions (Part
- 15), requirements concerning the normal station to network interface,
- and requirements concerning abnormal conditions on the local loop.
-
- Human factors of the station and the related service have not been, for
- the most part, specifically addressed. Good human factors design,
- however, is crucial to a successful product, and underlies many of the
- requirements.
-
- 1.3 General Operation of the Station
-
- This document describes a station similar to Charge-a-Call stations,
- with features added to read a magnetic-stripe card and conveniently
- select an IC to handle the call. This station needs to provide four
- basic functions:
-
- Voice-band transmission and reception,
-
- Addressing the far end party,
-
- Selection of a carrier,
-
- Relaying appropriate billing and call status information.
-
- The first two functions are common to all telephone stations. Carrier
- selection is a relatively new function and one of increasing importance.
- Relaying of billing information is a function inherent in public
- stations.
-
- The station described in this document will operate as a typical modern
- telephone with respect to voice-band transmission and reception.
- Addressing the far end will be done by standard Dual-Tone
- Multi-Frequency (DTMF) signals.
-
- The station will provide the customer at least one way to select an IC.
- One way lets the customer dial a particular sequence of digits on the
- DTMF key pad. This includes speed code dialing or 7-digit access numbers
- for carriers, as well as equal access carrier codes (10XXX). A second
- way allows the customer to select certain ICs by pressing a single
- button on a button field distinct from the DTMF key pad. This is
- sometimes referred to a "Select-a-Carrier" or Choose-a-Carrier" feature.
- The station will have to translate the single button activation into an
- appropriate sequence of DTMF signals, but this translation will be
- largely transparent to the customer. A third potential way that could be
- implemented in combination with the first two ways would have an IC code
- on the magnetic stripe of a Calling Card. This Calling Card could be
- issued by a BOC or by the IC. If the BOC issued the Calling Card, the
- call would be directed to that carrier for inter-LATA calls unless the
- customer overri des. If the IC issued the Calling Card, the carrier
- selection could not be changed.
-
- The station will provide the customer three ways of entering billing
- information. The first tow ways are available on today's Charge-a-Call
- stations and involve entering information by voice to an operator, or by
- use of the DTMF key pad. The third way allows the customer to enter
- billing information by physically presenting a magnetic-stripe credit
- card to a card-reading device in the station.
-
- In general, the station will need enough intelligence to perform the
- following functions:
-
- Accept carrier selection and billing information from the customer.
-
- Store some of that information for later use in completing the call, if
- it is not immediately needed.
-
- Communicate billing and/or addressing information to carriers or
- associated processors, possibly according to more than one protocol.
-
- 2. Station Requirements
-
- Two types of features of the station are described in this document. The
- word "should" indicates a mandatory requirement. "It is desirable"
- indicates a non-mandatory feature. These requirements are dynamic and
- could be influenced by time, technology, market strategy, or economics.
-
- 2.1 Card Reader
-
- The card reader and its associated electronics needs to provide four
- basic functions: accept the card from the customer, read it, and get it
- safely back to the customer; perform certain checks on the data encoded
- on the magnetic stripe; separate the card data into meaningful data
- fields and store each field for use when and if it is needed; and notify
- the customer about errors or invalid cards.
-
- This document does not specify a type of card reader. Any type may be
- used, as long as it can be easily used by the customer. Some of these
- requirements pertain only to particular card reader types.
-
- 2.1.1 Card Presentation
-
- 1. When the customer presents a card to an off-hook station, the card
- reader should read the card, check its validity (see Section 2.1.2), and
- store the data for use during call set-up by the station.
-
- 2. Any card data should be purged from the station after the station
- goes on-hook.
-
- 3. If the card reader type entails the customer releasing the card while
- it is being read, the station should alert the customer to remove the
- card from the reader before sitting up the call. The station should not
- proceed with the call setup until the card is removed. Also, it is
- desirable that part of the card always remain in sight of the customer.
-
- 4. The customer should be able to remove the card at any time, even
- while it is being read.
-
- 5. The card reader should be positioned such that the customer action is
- natural. If the customer moves the card in a vertical slot, the motion
- should be downward. In a horizontal slot, the card should be moved from
- left to right. For insertion type readers, the card should be pushed
- forward and then removed.
-
- 6. If the customer must move the card past the reader head, the card
- reader should successfully read the card over the range of speeds that
- the customer might reasonably attempt to move the card.
-
- 7. The customer should receive tactile feedback when presenting the card
- to the card reader, as well as feedback when the card is read
- successfully.
-
- 2.1.2 Checks
-
- 1. The station should check the parity of each character. Each data
- character will be encoded on the card with an odd parity bit.
-
- 2. The station should do a Longitudinal Redundancy Character (LRC)
- check. The LRC is a check character for the remaining data on the
- magnetic stripe. The first four bits in the LRC check the corresponding
- bits in the other characters on the magnetic stripe. Each bit is an even
- parity bit that checks the corresponding bits in the other characters on
- the card. The fifth LRC bit is an odd parity bit for the LRC itself.
-
- 3. The station should check the format of Calling Cards for proper
- layout of the data on the card. The format is specified in Section
- 2.1.3. If the four digits of the PIN are zeros, the actual PIN is not on
- the card.
-
- 4. It is desired that the station not check the expiration or effective
- dates on the card.
-
- 2.1.3 Card Characteristics
-
- 1. Calling Card characteristics are covered thoroughly in Reference (3).
- Both Calling Cards and CCCs will adhere to standards set by the American
- National Standards Institute (ANSI) and the American Bankers Association
- (ABA).
-
- 2. The Calling Card data will be contained on Track 2. The first
- character will be a start sentinel. The next six characters will be a
- one-digit major industry identifier, and a five-digit issuer identifier.
- A ten-digit billing number will be encoded in the next ten characters,
- followed by a Luhn mod 10 check character and field separator. The next
- four characters will contain an expiration date. Following the
- expiration date, the four-digit Personal Identification Number (PIN)
- will be encoded. The magnetic stripe may also contain up to another 11
- digits of data used to describe various services. Three of the
- characters may be a carrier identifier, or may be unused. The next 8
- potential characters are, at this time, unused. Unused characters will
- not be encoded on the magnetic stripe. The end sentinel will follow the
- last data character, and the LRC will follow the end sentinel.
-
- 3. The start and end sentinels should be transmitted as DTMF tone D. The
- separator characters should be transmitted as DTMF tone C. The LRC
- should not be stored or transmitted as card data. Thus, no more than 39
- characters of magnetic stripe data will need to be stored by the
- station.
-
- 4. If the last four characters of the 14-digit Calling Card number are
- zeros, the Calling Card PIN is not on the magnetic stripe. The specific
- data fields to be transmitted are specified in Sections in 2.4.
-
- 5. The station should be capable of being field modified to accommodate
- changes in the format of the card. 2.1.4 Error Feedback
-
- 1. The station should provide feedback to the customer for the following
- problems on card presentation and reading:
-
- a. The magnetic stripe on card is damaged, causing errors in reading.
-
- b. The customer presented the card in the wrong orientation. The station
- should include clear user instructions, or graphics, on how to present
- the card.
-
- c. The card is not an acceptable CCC or Calling Card (i.e., issuer or
- industry identification is inappropriate).
-
- 2. It is desired that the station respond to these errors by emitting
- tones, or by sending inband signals to the network, as appropriate. The
- inband signals should be sent using DTMF tones, using the codes defined
- in Section 2.4.4.
-
-
-
-
- 2.2 Customer Signaling
-
- The station is expected to accommodate three basic customer signaling
- functions: carrier selection via either the DTMF key pad,
- "Select-a-Carrier" buttons, or carrier pre-selection on the Calling
- Card; far-end party address signaling; and possible manual dialing of
- billing information. In addition, the station is expected to incorporate
- anti-fraud features.
-
- 2.2.1 Carrier Selection
-
- 1. The station should implement either Select-a-Carrier buttons or allow
- manual dialing of carrier access codes, or both.
-
- 2. If a method is implemented, it should be implemented according to the
- requirements in Sections 2.2.1.1 and 2.2.1.2.
-
- 3. It is desirable that the station accept carrier specific Calling
- Cards as described in Section 2.2.1.3.
-
- 2.2.1.1 Separate Select-a-Carrier Buttons
-
- 1. Positive feedback (an appropriate combination of aural, visual, and
- tactile), should be provided when a button is pressed.
-
- 2. The number of buttons should be kept to a reasonable level. It is
- suggested that no more than 12 buttons be provided.
-
- 3. When transmitting the number to the local office, that is, when using
- the station as a Select-a-Carrier station, the station should substitute
- an access number or a speed calling code for the button pressed. The
- access number may be up to twelve digits. The speed calling code may
- combine digits with the * or # signal.
-
- 4. When transmitting to a processor (dial-up or directly connected, as
- described in Sections 2.4.4 and 2.4.5), the station should transmit
- 10XXX or *XXX for the button pressed.
-
- 2.2.1.2 Manual Dialing of Carrier Access Code
-
- 1. The station should transmit all digits dialed on the key pad as they
- are entered.
-
- 2.2.1.3 Pre-Selected Carrier on Card
-
- 1. If the station reads a Calling Card with a carrier code included on
- the magnetic stripe in the optional field (see Section 2.1.3), the
- station should direct the call towards a processor (as explained in
- Section 2.4).
-
- 2. If the issuer identifier is '8555', the card is an IC Calling Card
- issued by AT&T Communications (ATT/C), even though these cards will not
- have a carrier code in the optional field on the magnetic stripe. These
- calls should be directed towards AT&T/C.
-
- 2.2.2 Address Signaling
-
- 1. The station should allow the customer to dial the terminating number
- before or after carrier selection.
-
- 2. These dialed numbers should be expected from the stations:
-
- a. 0+7/10 Digits
-
- b. 01+Country Code+National Number (7 to 12 digits in CC+NN)
-
- c. 411, 611, 911
-
- d. (0,1)+800+7 Digits
-
- e. 0-
-
- f. (1)+555-XXXX
-
- g. (1)+NPA-555-XXXX
-
- h. 950-XXXX, if a carrier is not selected in another manner.
-
- 3. The local office can block all other dialing sequences that may be
- dialed. Thus, it is normally not required for the station to screen for
- improper dialing sequences. If a BOC specifies that it is necessary to
- do so, an optional feature could allow the station to block all or most
- calls not on the above list.
-
- 4. It is desirable that the station enable new calls to be placed
- without reusing a card. The method to make sequence calls will be
- determined.
-
- 2.2.3 Anti-Fraud Features
-
- 1. The station should prevent the customer from signaling via
- manipulation of the switchhook.
-
- 2. For loop-start lines, the station should disable the dial until dial
- tone is received. For ground-start lines, the local office can detect
- DTMF tones as soon as current is provided to the station.
-
- 3. The station should mute or otherwise control the transmitter during
- any time where an acoustic coupler could be used for fraud purposes. In
- particular, the transmitter should be muted or controlled during the
- transmission of the card number and whenever the dial is disabled.
- Specific requirements on when to mute or control the transmitter are
- detailed in Sections 2.4.4 and 2.4.5.
-
- 2.3 End Office Interface
-
- Electrical and signaling characteristics of the station should meet the
- requirements described in: Reference (1) concerning the normal station
- to network interface; Reference (2) concerning abnormal conditions on
- the local loop. The station should also meet requirements specified by
- the FCC rules regarding registration of telephone sets.
-
- 2.3.1 Features of Line
-
- 1. The station should operate on a line with Charge-a-Call class of
- service. This class of service allows only nonsent-paid and free calls.
- An optional feature may allow the station to operate on lines without
- Charge-a-Call class of service, as described in Section 2.2.2, item 3.
-
- 2 The stations should operate with any electronic end office commonly in
- use by the BOCs.
-
- 3. The station should operate on either standard loop-start or
- ground-start lines.
-
- 4. Answer supervision cannot be provided on these lines. Thus, the
- station should not depend on answer supervision for any functions.
-
- 2.3.2 Electrical Characteristics
-
- 1. The loop current from the local office to the station will be a
- minimum of 23 milliamps at 48 volts DC. It is desirable that the station
- operate on this power level without a supplementary power supply. If the
- station needs more than 23 milliamps current, a supplementary power
- source may be used.
-
- 2. The polarity of the loop should not affect operation of the station.
-
- 2.3.3 Signaling Characteristics
-
- 1. The station should operate on lines with DTMF signaling, also know as
- Touch-Tone.
-
- 2. When dialing Calling Card, CCC, or IC access numbers, the station
- should transmit digits at a maximum rate of 10 per second. The tone
- duration and interdigit interval should not be less than 50 ms and 45
- ms, respectively, and the cycle time (sum of tone duration and
- interdigital time) should not be less than 100 ms. It is desirable that
- digits be transmitted at close to the maximum rate.
-
- 2.4 Carrier and Processor Interfaces
-
- These stations should interface either with a carrier or with a
- processor (designed to interface with one or more carriers), depending
- on instructions programmed into the station.
-
- It is proposed that the station be kept simpler by using identical
- protocols to all ICs whenever feasible. Still, the need for different
- protocols is envisioned for direct station-carrier interfaces. Carriers
- using Feature Groups A or B would conform to a single protocol from
- these stations (currently undefined). Feature Group D carriers, except
- for ATT/C, might need to conform to another standard protocol. ATT/C,
- whether Feature Group C or D, would use a third protocol. These
- protocols are described in Sections 2.4.1 through 2.4.3. The station
- would determine which protocol to use based on the customer's actions to
- select the carrier.
-
- An interface to a processor could be substituted for the carrier
- arrangements. The processor would, in turn, establish and administer the
- interfaces to the ICs. The processor could be dialed up by the station
- or directly connected. Call sequences and station actions for dial-up
- and directly connected processors are described in Sections 2.4.4 and
- 2.4.5, respectively.
-
- The station should be programmable to send all calls of certain types to
- a dial-up processor, and handle others by the protocols described for
- the various carriers. Section 2.4.4 specifies the calls that should
- cause the station to dial the processor. The dial-up processor would
- then handle the call set-up for those calls. Calls where the customer
- begins the call by dialing a number or selecting a carrier would be
- handled using Charge-a-Call treatment or direct interfaces to the
- carriers.
-
- 2.4.1 Call protocol for BOC and ATT/C (Feature Group C)
-
- 1. BOC and ATT/C (FG C) calls are set up by the customer dialing 0+ the
- terminating number after receiving dial tone. The station should then
- wait for the "bong tone" from the TSPS. The bong tone is defined to be
- 100 ms or the DTMF frequencies for the # sign, 941 and 1477 Hz, followed
- by 1.4 seconds of dial tone, 350 and 440 Hz. The amplitude of the signal
- starts at -7dBm0/frequency +/- 1dB at -3 TLP. The amplitude of the dial
- tone portion is exponentially decayed with a time constant of 200 ms.
- The amplitudes at the station can vary by loop. The range of amplitudes
- will be determined.
-
- 2. The station should be able to prefix a digit (e.g., '9') before the
- first customer-dialed digit. (This feature should only be used if it
- cannot be avoided. This feature could cause human interface problems.)
-
- 3. The station should then transmit only the 10 (if PIN not on card) or
- 14 digits of the BOC or AT&T Calling Card number (as explained in
- Section 2.1.3.
-
- 4. The station should begin transmitting the Calling Card number within
- 500 ms or recognition of the bong tone. It is desirable that the digits
- be transmitted at the maximum rate.
-
- 2.4.2 Call Protocol for Feature Groups A or B IC
-
- The call protocol for Feature Groups A or B ICs will be determined later
- if any ICs are interested in being accessed directly by the stations.
-
- 2.4.3 Call protocol for Feature Group D IC
-
- The call protocol for Feature Group D ICs will be determined later if
- any ICs are interested in being accessed directly by the stations.
-
- 2.4.4 Call sequence for Dial-Up Processor
-
- 1. The station should dial the processor number, as programmed, only if
- a customer presents a card to the station first. The station should be
- able to store and dial a one-to-seven-digit processor number.
-
- (EXCEPTION) ((If an AT&T Calling Card is presented to the station first,
- the station should store the card number and handle the call as
- described in Section 2.4.1.))
-
- 2. When a processor is connected, the station should detect a bong tone
- that indicates the processor is ready to receive DTMF signals. The
- station should then transmit a calling station identification (up to ten
- digits, if required),DTMF tone 'D' and all the data from track 2 of the
- magnetic stripe of the Calling Card or CCC, DTMF tone 'D' again, and the
- carrier access code (10XXX), if a carrier is selected. The processor
- will have announcements to prompt the customer, but the station should
- transmit the data after detecting the processor tone, or as soon as the
- customer provides the information, whichever is later.
-
- 3. The station should begin transmitting the calling station
- identification within 500 ms of recognition of the tone. It is desirable
- that the digits be transmitted at the maximum rate.
-
- 4. The station should disable the transmitter in the handset during
- transmission of the processor number until the card number and DTMF tone
- 'D', a 3 digit code, and DTMF tone 'D' again for these messages to the
- processor:
-
- CODE MESSAGE
-
- 011 Card not readable (failed parity check) 002 Not an
- ANSI-standard Card 003 Self-diagnostic indication of card reader
- trouble 08X,09X Give announcements in specified language
-
- Other codes and messages will be assigned when needed.
-
- 6. The station should allow the customer to dial the terminating number
- or carrier codes any time after the billing data are transmitted.
-
- 7. If the customer dials a number first (could include dialing a
- carrier), the station should transmit all digits dialed and monitor for
- a bong tone. If it detects a bong tone, it should transmit a 14-digit
- Calling Card number if one was read, or allow manual dialing; if no bong
- tone is detected within five seconds after the last digit dialed, the
- station should transmit any card number read after that time.
-
- 8. If the customer presses a Select-a-Carrier button first, the station
- should transmit the code stored for that button. The station should then
- operate the same as if a number had been dialed first. However, the card
- data transmitted may be carrier specific.
-
- 9. After receiving the processor tone, the station should read out the
- last card number read.
-
- 2.4.5 Call Sequence for Direct-Connect Processor
-
- 1. The station should accept inputs from the card reader, the DTMF dial
- pad, or a Select-a-Carrier button pad when the handset is off-hook.
-
- 2. After a card is presented with the station off-hook, the station
- should send DTMF tone 'D', the data from track 2 of the magnetic stripe
- of the Calling Card or CCC, and DTMF tone 'D' again. The dial pad should
- be disabled while the station is transmitting the card data.
-
- 3. The station should send the codes described in Section 2.4.4, if
- appropriate, instead of the card number.
-
- 4. The transmitter should be disabled from the time the handset goes
- off-hook until a card is presented and transmitted, or until a digit is
- dialed. This prevents a customer from acoustically coupling DTMF tone
- 'D' and a stolen or made-up card number into the handset.
-
- 5. If a card is presented first, the station should transmit the carrier
- access code if a carrier is selected, or allow the customer to dial.
-
- 6. If a number is dialed first, the station should not transmit any
- carrier codes, and should only transmit card data after it receives a
- bong tone, or waits at least 5 seconds after the last digit dialed and
- then reads a card.
-
- 2.5 Physical and Other Requirements
-
- The station will be composed of several major physical components.
-
- 2.5.1 General
-
- 1. These requirements specify a station to operate in a public, indoor
- environment.
-
- 2. All components of the station should be flame resistant.
-
- 3. The station should be built to withstand the abuse expected in a
- public environment.
-
- 4. It is desirable that self diagnostics be designed into the card
- reader.
-
- 5. The station should not be susceptible to radiated emissions from
- other sources that are within legal limits. It is desirable that the
- station not be susceptible to any radiated emissions from other sources
- that may reasonably be encountered.
-
- 2.5.2 Card reader
-
- 1. The card reader should be designed such that the reader head cannot
- be easily damaged by misuse or abuse encountered in a public
- environment.
-
- 2.The card reader should be protected to minimize the frequency of
- cleaning.
-
- 3. The card reader should be easily maintained.
-
- 4. The card reader should be physically shielded from the interior of
- the set such that customers cannot access or tamper with the electrical
- components of the station.
-
- 2.5.3 Dial Pad
-
- 1. The dial pad should be will designed from a human factors standpoint
- with respect to button spacing, shape, graphics, and activation
- feedback.
-
- 2. The station should have a moisture and dirt resistant dial pad.
-
- 3. The dial should be durable. Each key should withstand at least
- 500,000 depressions before failure.
-
- 2.5.4 Handset and Switch-hook
-
- 1. On wall sets, the handset should be connected to the station with a
- cord that can withstand a 400 pound tensile test.
-
- 2. The handset cord should have enough cutting and shear resistance to
- withstand attacks by tools such as knives or scissors. Tools with
- cutting ability equal to or less than 5-inch diagonal cutters should not
- be able to sever the cord.
-
- 3. When destroyed while in service due to any circumstances, the cord
- should not create a customer safety hazard.
-
- 4. The handset should be manufactured such that it cannot be
- disassembled by customers or field craftspersons. The handset and cord
- should only be replaceable by opening the station housing.
-
- 5. The handset should allow people with hearing impairments to use the
- telephone with their hearing aids. The station should meet the
- Electronics Industries Association's Recommended Standard, RS-504,
- Magnetic Field Intensity Criteria for Telephone Compatibility with
- Hearing Aids, to be considered hearing aid compatible. This capability
- should be shown by use of a blue grommet on the handset cord.
-
- 6. The handset and switch-hook should be able to withstand at least
- 200,000 hang-ups before failing.
-
- 2.5.5 Station Housing
-
- 1. The wall station should be capable of being mounted in standard
- enclosures currently used by BOCs, including 10A-type enclosures and the
- 178A backboard.
-
- 2. It is desired that the station be equipped with locks to discourage
- theft of the set or tampering with the program codes.
-
- 3. Space should be available on the face of the set to provide
- instructions for use of the set, and to place the telephone number and
- station location information.
-
- 3. Support
-
- This section defines the obligations of the supplier to support the
- station. Additional requirements are to be determined.
-
- 1. The supplier should provide documentation for the installation,
- maintenance, and testing of the stations.
-
- 2. The supplier should provide satisfactory means for replacement parts.
-
- 3. The supplier should have a factory repair service, or similar means
- for refurbishment, for repairs that cannot be made in the field.
-
- 4. The supplier should provide data on the reliability of the station
- and each major component.
-
- 5. The supplier should have an adequate quality assurance program,
- including a means for handling engineering complaints on product design,
- manufacturing, operation, maintenance, documentation, and other aspects
- of the product.
-
-