Many new models of hearing aids are immune to interference when a mobile phone is brought up to the same ear as the hearing aid. The result depends on the level of immunity designed into the hearing aid, the nature of the hearing loss and the type of mobile phone. Unfortunately many types of older hearing aids may be susceptible to interference making it very difficult to use a mobile phone. Should interference be experienced, there are several things that can be done which may improve the situation:
- If possible use the mobile phone at the non aided ear;
- Use a different, more immune hearing aid;
- Use a hands free accessory. Different accessories can be coupled to the hearing aid by either using the Microphone or T-Coil position.
- Vibrating batteries are also available.
Most new models of hearing aids are also immune to radio frequency interference from mobile phones that are more than 2 metres away, so interference by other mobile phone users is unlikely.
The GSMA has produced further information in conjunction with the European Hearing Instrument Manufacturers Association (EHIMA) to answer questions in more detail regarding this issue.
We are currently supporting related research.
When someone is using a mobile phone near to a hearing aid user:
With the introduction of digital mobile phones it has become apparent that they may cause interference to a range of audio equipment including hearing aids.
The interference is caused by the type of radio signals that are transmitted from the digital mobile phone being picked up by the hearing aid amplifier. The interference decreases rapidly as the distance between the mobile phone and the hearing aid increases. For this reason there has been no reported problem from the base stations that transmit signals to mobile phones.
The chance of a hearing aid wearer getting interference from a mobile phone will depend upon a number of factors such as:
- The distance the phone is from the hearing aid,
- The level of the radio signal the phone is transmitting
- The immunity of the hearing aid i.e. its ability to reject interference to such signals.
In most situations it is a case of being practical about the problem. If the interference lasts just a few moments then it may be possible to let it pass. If however you are in a situation where someone is using their phone close to you for long periods of time you have a number of options:
- Move a short distance away if you can, this should reduce or remove the interference
- Politely inform the user that they are causing a problem with your aid and could they move a short distance away
- If this is a constant problem you should contact your hearing aid clinic or dispenser for advice on a new aid, as it is unlikely that anything can be done with your existing one.
When a hearing aid user wishes to use a mobile / cordless phone:
With the introduction of digital mobile phones it has become apparent that they can cause interference to a wide range of audio equipment including hearing aids.
Anyone who wears a hearing aid and is considering the purchase of a mobile phone should ensure that their hearing aid and the mobile phone will work together.
Research has shown that some mobile phones cause more interference than others do and that some hearing aids are more susceptible than others to interference from digital mobile phones.
The interference is caused by the type of radio signals that are transmitted from the digital mobile phone being picked up by the hearing aid amplifier. The interference decreases rapidly as the distance between the mobile phone and the hearing aid increases. For this reason there has been no reported problem from the base stations that transmit signals to the mobile phones
There is now an international standard that sets the level of immunity for hearing aids, and all new models of hearing aids will comply with this. This means that users of new hearing aids being used 2 metres or more away from a mobile phone should find any interference reduced to levels low enough to allow their aids to be used with little difficulty. The new products of all EHIMA member companies meet these specifications. However older hearing aids may have problems.
However due to the way signals are transmitted by mobile phones it still may not be possible to use a digital mobile phone in the normal manner with a particular hearing aid. The hearing aid industry is working towards further compatibility standards which aims to allow hearing aid wearers to use mobile phones in combination with their hearing aid as other people do. The mobile phone industry has also responded by supporting research and with the development of specialised hands free accessories.
The problem is becoming more complicated due to the fact that new phones are being introduced that operate on two widely separated frequencies, known as dual band operation. Users will not know which frequency the phone is operating on and while a hearing aid might work satisfactorily with a mobile phone at one frequency it may be unusable at the other frequency.
2. What solutions exist if a hearing aid user suffers from interference from a digital mobile phone?
There are several things that can be done which may improve the situation
- If possible use the mobile phone on the non-aided ear
- Try a different mobile phone to check for any improvements (see Question 3).
- Use a hands free kit (see Question 12). Different accessories can be coupled to the hearing aid by either using the Microphone or T-Coil position.
- Use a different, more immune hearing aid (see Question 5).
It has been shown that there can be considerable differences between mobile phones in terms of the interference they cause to a hearing aid wearer. Therefore it is worth trying different mobile phones before you consider changing your hearing aid. At the moment it is still possible to obtain analogue mobile phones and you may wish to consider using these for the time being. However they will disappear from the market in a few years time. You should also consider using a "hands free kit", (see Question 12)
Before thinking of changing your hearing aid it would be worth while to try different mobile phones to see if there is one that is suitable (See Question 3). Some hearing aids have higher levels of immunity to interference than others. In general smaller aids worn in the ear have higher immunity, than those worn behind the ear. It is important for the user to try a new aid with a mobile phone to confirm that it does not cause interference before accepting it. It is also important to remember that the power level of the phone?s transmitter changes with geographic location and therefore the radio signal is likely to be greater in a rural situation than in the centre of a town. The radio frequency that the phone is using may also change if it is a dual band model. The phone should therefore be tested in a range of situations with the hearing aid, as it may not be satisfactory in all conditions of use.
Most new models of hearing aid reduce the interference from GSM phones to acceptable levels if they are more than 2 metres away. Some are also immune to interference when the phone is brought up to the same ear as the hearing aid. The result depends on the level of immunity designed into the hearing aid and the type of mobile phone. Unfortunately many types of older hearing aids are likely to be susceptible to interference making it very difficult to use a mobile phone.
The aid user will hear a buzzing sound, which grows louder as the phone is moved nearer to the aid. Normally the GSM phone will only cause significant interference when it is closer than 2 metres from the hearing aid user.
Driving safely is of paramount importance to everyone on today's busy roads, and mobile phones should be used responsibly while on the move. The industry has developed a wide range of equipment and features to help you do this and the use of a professionally installed car-kit is recommended. (Note: it is an offence in many countries to hold a mobile phone to the head while driving.) However, the GSMA advises that it may be sensible to pull over during difficult traffic conditions or when calls are likely to be long, complex or emotional. The GSMA advises drivers at all times to obey the national laws of the country in which they are travelling and to follow common-sense advice to avoid distractions.
To check if the interference is coming from a GSM phone, first check that the hearing aid is not malfunctioning due to acoustic feedback (earmould not fitting properly) or any other reason. Then try moving a mobile phone which is engaged in a call near to the hearing aid and listening for interference.
No, the hearing aid will return to normal operation when the phone is removed from the vicinity of the hearing aid.
No. It may cause some discomfort due to the loudness of the sound and its rasping nature but due to the way your hearing aid should be set up it will not damage your hearing.
Not necessarily, indeed some aids are worse on the "T" position. We are not aware of any current mobile phone which has an inductive coupler for use with a hearing aid on the "T" position. However "hands free" kits (see the question below) may provide the necessary form of coupling. As with all solutions the user should check that the phone, with any attachments, and the hearing aid would work together satisfactorily.
Hands free kits are devices which plug into the base of a mobile phone and allow the user to speak into a microphone and hear a reply through an earphone or loudspeaker (see Figure 1). The advantage to hearing aid users is that the kit allows the phone to be used away from the ear and the hearing aid, significantly reducing the likely level of interference. In addition inductive coupling can be provided in conjunction with, or in place of, an earphone. Some mobile phone manufacturers are now providing such facilities but you may find that they will only fit certain models in the manufacturer's range.
GSM stands for Global System for Mobile communication, and is a cellular radio communications system used in more than 140 countries world-wide including most European countries. GSM phones operate by means of a digital system of radio transmission. The GSM system requires that the radio signal is switched on and off very rapidly (217 times a second) to carry the messages. In analogue phones the radio signal is almost constant. Analogue phones use a similar system to your FM radio and do not generally cause a problem with interference. Analogue phones are likely to be phased out of service within five years in many countries.
Cordless phones may work with an analogue radio frequency signal to connect the handset to the base station or use a digital system. Currently many cordless phones use a digital system called DECT. The analogue phones do not generally cause a problem with hearing aids but the DECT system may cause problems in the same way as the GSM mobile phones. Hearing aid users may therefore also experience interference from DECT phones and should check that there are no problems in using the cordless phone before they purchase it.
It has to be dealt with in the same way as for mobile phones. See Question 2.
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