Based on our own experience, surveys and evaluations, we provide some "good practise" recommendations for developing sound and other multi-sensory techniques for accessible communications and education

Accessible education and communications should be developed and marketed for everyone, not just for disability groups

An accessible (e.g., multi-sensory) experience is richer for everyone, even if they do not have a diagnosed disability. It is well known that communicating information in multiple ways can help everyone's ability to retain and learn new information. People have a variety of learning preferences. Therefore, the benefits of multi-sensory communications in an educational context is clear. A multi-sensory experience for public communications can additionally be much more enjoyable and invoke deeper emotions.   As another example, an audio description of a visual image or diagram could help everyone to find and interpret what is in the visualisation, even for those with full vision.  Therefore, the development of accessible resources should be considered as a benefit for everyone. This will also ensure a much bigger user base and make their development more economically viable.  Universal Design in a good approach to consider. 

Work to market your resources as beneficial for everyone

We note that there can sometimes be a perception, including from education and communication leaders, that accessible resources will not be suitable for `main stream' audiences. Therefore work needs to be done to demonstrate that this is not the case, and you should consider how best to market the resources as suitable and beneficial for all (not just for audiences with disabilities).

Do not be afraid to use multiple modalities for all audiences, but use them carefully to avoid sensory overload

For example, including visuals to complement audio or tactile resources is still useful for a specific goal of increasing accessibility for blind and vision impaired audiences. Audience members may have a broad range of levels of vision, and make use of the visuals to different degrees. There may also be fully-sighted guides, and other participants, joining in with the resources.  Consider that multi-modalities communicate the same information and not multiple information in parallel, to avoid a sensory overload. 

Wherever possible, involve persons with a disability in the design process and seek consultation from specialist teachers and multi-disciplinary experts

Working with the target audience during the design process, will naturally lead to a product or practise that is better at achieving its objective. Consultation with experts in a range of appropriate fields, such as sound perception, sound design, psychoacoustics and user experience and design can make a huge difference for producing effective resources. Working with specialist teachers of pupils with disabilities is hugely beneficial. They have experience in understand what does and does not work in the educational context for pupils with disabilities. Rigorous approaches to user testing and evaluation should also be included wherever possible, to improve design and demonstrate efficacy. Proven success will ultimately lead to wider uptake of accessible approaches to education and communications. 

Make careful choices on how to use different modalities, based on the goal of the communication and the benefits of using different senses

Understanding the goal of your communication or educational resources is an important place to start. You are likely to make very different choices if your primary goal is to inspire or invoke an emotional reaction, compared to a primary goal which is to perform detailed scientific analyses of a dataset. For example, for the former goal, if you wish to map some property of a data set to sound, then you may employ an approach which sounds very pleasant to listen to, but is not very accurately or directly tied to the data.  For the latter goal, pleasantness may be less important than accuracy. 

Consider the strengths of our different senses when making design choices

Our different senses also have different strengths. For example, our ears have tremendous dynamic range and temporal resolution (i.e., the ability to distinguish extremely differences and hear patterns), but not great spatial resolution (i.e., the ability to find the location of a sound). 

Provide clear context to the audience before playing sounds which represent concepts or data or when providing tactile models

Audiences are generally not used to the idea of representing abstract concepts, or other types of data, with sound. Therefore it is difficult for them to quickly interpret the sonifications. It is basically impossible with no context. Therefore, the audience must be introduced to the concept of turning light into sound, with sufficient information for the audience to interpret what they hear. Likewise, a tactile model will need to be interpreted, and context and guidance must be given. This context could be using a live narration,  recorded voice description or written explanation (which should be accessible to screen readers).  We should remember that most information is currently communicated visually in schools and other educational settings. Therefore, we should expect that time is needed for new audiences to adapt to exploring information with different modalities. 

Give a clear explanation of what the audience should expect in advance of the experience and use enabling, rather than directional, language

Several disability groups benefit from a clear warning/guide of what to expect, especially when the experience is very new to them. They can also benefit from plenty of processing time (slow pace). For example, if a loud sound will be played, a warning should be given in advance. If an audience member is to touch a strange object, briefly describe what they are going to do first, so that the audiences know what to expect. Using enabling language rather than directorial language can make a learning experience much more rewarding and powerful for an individual. For example, when it comes to interacting with tactile images, rather than telling a user what they should be feeling, direct them to part of the image and ask them to tell you what they are feeling. You can then talk about the feature that they have discovered together.

Using physical materials, or expensive technologies, as a mandatory component can limit reach and dissemination

Depending on the goal of your resources, you should consider how widely they can be used and adopted. If you wish for your resources to be easily used by others, then they should be easily accessed at little-to-no cost and easily used without specialist resources or technologies.  For example, whilst audio files can relatively easily be shared over the internet, tactile models are more prohibitive due to the challenges and costs of manufacturing them in large quantities.  Remember that many persons with disabilities across the world will not be economically privileged, nor have access to specialist equipment or resources. Therefore, you may consider versions of your resources which do not require specialist equipment or resources to share more widely.

Be aware of cultural differences

People across the world have different cultural experiences, which may change how they experience multi-sensory experiences.  For example, using sounds to represent information which are primarily best in a Western musical system, may not be as easy to interpret (or indeed enjoyable to listen to), for people who have less exposure to Western music. If aiming to reach audiences from a variety of cultures , seek consultation with representatives from those groups to establish how the approaches might be changed or adapted. 

Some of the recommendations above can also be found in the following articles

We also thank the Tactile Universe project for contributing to these recommendations.