03.02.17

Induction loops lacking a global audience

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The benefit of induction loops to those with hearing problems has been proven for some time now, so why do adoption rates differ so much according to the country and type of building you are in? Steve Montgomery finds out.

Hearing loss affects millions of people around the world.  An estimate in 2015 by the World Health Organization found that 360 million people worldwide (5% of the world population; 328 million adults and 32 million children) have moderate to profound hearing loss in both ears and the number of people worldwide with all levels of hearing loss is rising.  Fortunately technology can help.  Hearing aids have been available for many years, and the addition of localised hearing loops has supplemented the basic amplification to enhance the sound quality and availability of live interaction and performances.  

Hearing loops operate by means of induction loops that transmit audio signals to compatible T-coils in users’ hearing aids.  In the UK and Europe these system are commonly available and are becoming more so in America and other areas.  The benefits extend beyond the quality and availability; the hearing aid may be individually tuned to the user’s own hearing capability, and the sound itself will be free from distracting background noise, making it a much more effective and enjoyable experience.

The primary market driver for hearing loops is legislation.  It is nowadays a common and established technology in countries that dictate the use of assistive listening devices in public spaces as part of their equality of access laws or building codes.  They are well-received by users.  Alistair Knight, marketing director of Ampetronic, points out: “Hearing loops have been the default form of assistive listening in Europe, Scandinavia and Australasia for over 25 years as it’s the most popular solution with hearing aid users.  They don’t have to identify themselves by asking for a receiver and the sound is personalized to their requirements by the hearing aid set-up.  America remained the only large market with strong assistive listening legislation that didn’t take this approach for many years, as installers adopted a preference for FM and Infrared solutions.  Many of the hearing aid manufactures didn’t fit a telecoil in their products as standard, which compounded the problem as users couldn’t use the systems even if they found them.

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“However, over the last 10 years, Americans with hearing loss have travelled around the world and experienced hearing loops themselves.  As a result they have campaigned for change and started their own advocacy groups to promote the technology.  It is becoming more widely known across the states too, with approx. 85% of all hearing aids now having telecoils fitted.”

However, the installation and operation of hearing loop systems are not without problems.  A primary issue is that the legislation covers the requirement but not the quality or performance.  In fact legislation in the UK is itself not clear.  It refers to the need for owners of buildings to make ‘reasonable adjustments to make the building fully accessible”.  In a standards document of several hundred pages, just two or three refer to hearing loops.  Buildings often have the bare minimum system that meets compliance.  “This has been a problem, predominantly in the UK, for a long time now,” continues Knight. “It’s mainly a result of our legislation, which stipulates that assistive listening technology must be installed in public venues, but fails to state that it must be installed to perform to any standard, or be regularly tested and maintained.  It results in venues operating a ‘tick-box’ approach to the legislation and simply going for the cheapest, easiest option, even if it’s of no tangible use to people with hearing loss. There are more than enough installers who are willing to provide such a product or service as there is no real penalty for doing so.”

There are further problems. “Unfortunately induction loop systems can still be poorly considered and the people taking responsibility for their installations under-qualified to do so,” explains, Gary Leverington, technical services manager at Action on Hearing Loss. ”Maintaining it is as important as the initial provision. Industry standards and awareness have increased over the years and organisations such as Action on Hearing Loss can now supply correctly conceived and implemented systems.”

“Some of the equipment currently used in railway stations is not fit for purpose, as installations do not meet the required hearing loop technical standards (BS EN 60118-4:2015) ,” says Andrew Thomas, market development director of Contacta and current IHLMA chairman.  “This can be frustrating for users due to a lack of signal range, awkward placement and unclear signage. In any case, the installer must be competent and well trained in installing, setting up and measuring the signal coverage over intended areas, as well as considering any factors that may affect signal quality such as metal loss or other magnetic interference.”

Knight agrees: “Transient applications require a slightly different approach, as there are different considerations to take into account.  Potential users could be located anywhere in the space, and could be sitting or standing, requiring a uniform signal strength and full area coverage. However, that in itself doesn’t present much of an issue to an experienced system designer.  It’s the amount of metal in the buildings construction that most affects the level of difficulty as it absorbs the magnetic field produced by the hearing loop.

“In reality hearing loops are becoming more popular in these applications and can now be found more commonly in transport applications.  “We specialise in designing systems for trains, trams, coaches and taxis. For example the new fleet of Nissan cabs in New York City all have a hearing loop installed.”

It is much more difficult to provide in mobile applications than static ones.  “Loop system design and installation can be challenging and sometimes expensive.  Multiple amplifiers and wire grids aimed at providing access in all areas and grids can interfere with each other,” explains Mark Medcalf, Technical Product Manager, Williams Sound.  “Electric trains generate a lot of Electro-magnetic noise and often conflict with the loop systems.  Designing these systems is a challenge and there will likely be black areas between the wire grids.  Also maintaining consistent audio level to the hearing aid while mobile is almost impossible.”

The International Hearing Loop Manufacturers Association acts as the voice of the industry to governments and promotes the use of hearing loop systems, as well as offering technical advice and defining good quality standards and best-practice for the hearing loop and assistive listening industries.

There is a growing awareness and greater installation of hearing loops, particularly in the retail environment.  Banks, pharmacies and other personal-service retailers rely on good interaction and accurate communication with their customers and have been keen to install systems in their branches.  Supermarkets have expanded their availability, with some larger retailers now offering hearing loops on every other checkout, rather than just one in ten a few years ago.  It makes good financial sense. “Approximately 16% of the population has some form of hearing loss. That’s about 10 million people in the UK, representing about £50 billion of annual retail spend. So it’s worth providing a good level of service for people with hearing aids,” says Knight.

This increase in availability and performance may be a reflection of the work being done by Hearing Link, a UK charity that campaigns for better service.  Groups of volunteers go out into their communities and test the hearing loops, with the ones that don’t work being reported to the providers. Complaints are registered with the installer with the expectation of repair or replacement.

Hearing aids equipped with telecoils could, arguably, be classified as one of the forerunners of the BYOD concept: users were able to connect their hearing aid to a locally-provided service simply by switching to it.  In collaboration spaces and huddle rooms hearing loops are usable, but often a slightly different technology is required.  Leverington: “Hearing loops will only ever be as effective as the audio input that you are presenting to the space.  Chances are that the microphones that drive the loop may not be available for more informal discussions.  We can however provide a number of solutions such as elite listeners.”  In smaller rooms microphones can be connected to small infra read or RF transmitters linked to receivers and a small coil around the person’s neck.  This then transmits to the person’s normal hearing aid.

To be effective, assistive listening technology must satisfy some fundamental requirements: it must be able to broadcast latency-free audio to multiple people at the same time, directly to hearing aids and cochlear implants; be freely available to any individual who requires it and be simple to use. These factors mean that assistive listening has always been the reserve of audio frequency hearing loops, infra red and RF systems where the intended user of the system can either connect their hearing aid directly to the audio or check out a receiver supplied by the venue operator.  

Advances in technology are producing a range of new ways of digitally transmitting audio.  Smartphone apps that receive audio over Wi-Fi or Bluetooth are being developed, although they require software to be downloaded and run at the venue, so aren’t necessarily easy to use.  At the moment they also fail to meet two of the key requirements so are supplemental, rather than alternatives to hearing loops: legally, a service provider must offer the facility to everyone who wishes to use it which means that a sufficient quantity of receivers must be available and there must be no noticeable latency.  

Audio over WiFi has inherent latency, exacerbated by processing delay on the smartphone.  Delayed audio can create lip-synch issues, making lip reading more difficult.  However Sennheiser claims that its MobileConnect app exhibits almost latency-free transmission of audio-content.  “MobileConnect is primarily aimed at assistive listening and audio description applications, but the solution can also be used for simultaneous interpretation,” says Andy Niemann, director, business communication at Sennheiser. "It opens up completely new opportunities in situations in which audio transmission has until now been impossible or only very limited, such as digital signage, as well as in many areas of assistive listening.”

Under the Equality Act reasonable adjustments must be made to ensure that those with a disability are considered in all public buildings and services.  Electrical contractors tend to concentrate on small meeting rooms, community centres and reception desks and there is a growing number of specialist installers who service the requirements of retail outlets.  There is significant potential for AV installers to become involved in the installation of hearing loop and other, new technology, forms of assistive listening in applications such as higher education, large houses of worship, sports stadiums, cinemas and theatres, government centres and corporate spaces.