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Relay services

Dr John Gill
November 1995

Within the European Union there are millions of people with a hearing impairment sufficient to make it impossible for them to use the phone.

Text Telephones

Deaf people can obtain text telephones from various organisations in their own countries, and in some cases free of charge. The text telephone enables customers who cannot use the phone in the normal way to talk to each other using a keyboard with a integral display unit. Whilst this enables them to talk to the bulk of other deaf people who have the same equipment (and an increasing number of commercial companies), it does not really give them full access to the wider world of tele-communications. This is where the relay services come in.

Relay Service

A relay service is, in essence, a real time translation system which translates in both directions from text to voice and voice to text. The operation of the system is relatively simple, in that the originating customer calls the relay service, identifies themselves and informs the operator at the relay service of the number they wish to call. The operator calls this number and when the call is through, full translation can take place in either direction.

Voice Through

Many deaf people have good speech, particularly if their deafness occurs in later life, and consequently many relay services offer voice-through facilities. In this case once the call is established then the text-using customer can speak to the hearing customer directly and only employ the text system through the operator when the hearing customer is speaking to the deaf customer. This system saves time and increases the sense of "realism" of the call.


The charging for such a call has to be carefully considered if a relay service is to offer anything like an equivalent to a normal telephone conversation carried out in speech. Leaving aside the common assumption that a text call takes six times as long as voice calls to transmit the same amount of information, it can be seen from the operation of a relay service that there are two telephone calls where there would normally only be one. It is essential that the originating customer, be it text or voice, is only billed for the same amount of money as this would have been if the call had been dialled directly. To do anything else would be discriminatory.


The setting up and running of relay services also needs careful consideration, as well as the financial aspects of supporting such a labour-intensive service. In particular, it is essential to get the views of deaf people who will be using the service and make sure these are taken into account when setting up the service.

In some countries, notably Britain and the United States, co-operative ventures have been set up between telecom operators and the organisations which look of and for deaf people. For example in the United Kingdom the relay service, Typetalk, is a joint operation between BT and the Royal National Institute for Deaf People. BT provide the funding (around £4.5million per annum) and the RNID provide the expertise on deaf people, provide the operators and generally run the service. In the UK financing of this service is a licence requirement for the major operating company (BT), however other funding methods are in use in other countries.

Often where the operator is still a PTT (possibly government owned) the operation of a relay service is seen as a social necessity. In other countries where there is a more liberalised structure, legislation or licence requirements are needed to ensure that the operators pay for the establishment of a relay service.

In the United States a levy is placed on each customer's bill to produce a pool fund which is used to run the relay service. In the US operators are invited to tender to run the relay service and thus, for individual operators, a relay can actually be a profit-making enterprise.


One of the difficulties in there being universal access throughout the world to relay services is the large number of communication standards which exist. Even within recommended standards, such as V21, there are differences between the countries let alone the different alphabets used that prevent text phones talking to each other and any relay services.

The advent of the fledgling V18 standard is likely to be the first step towards the end of this complication, and hopefully deaf people can look forward to the establishment of a worldwide network of relay services financed as part of the normal telephone service rather than as a "special" facility.



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