Veronica With Four Eyes

Creating Audio Description For Science Experiments With YouDescribe

Today, I received a question from a science teacher asking if I had any tips for creating audio description for science experiments and science lab videos. Since they were going to be posting videos of science experiments to a class website, they wanted to ensure that the videos would be as accessible as possible for students with vision loss, as well as students who prefer to listen to videos instead of watching them. Here are my tips for creating audio description for science experiments for free with YouDescribe.


Audio description, sometimes referred to as descriptive audio or described video, is an additional narrator track that provides visual information for people who otherwise would not be able to see it. Audio description is provided during natural pauses in dialogue so it does not distract from the video. Occasionally, describers may pause the video themselves and add description if there are no natural pauses available.

For most online videos, open audio description is used, meaning that the audio description automatically plays and does not require a special device to be used.



YouDescribe is a free website and iOS app that allows viewers to watch YouTube videos with audio description. The audio description tracks are written and recorded by sighted volunteers so that people with blindness and low vision can watch YouTube videos and receive visual information. YouDescribe is a project of the Smith-Kettlewell Eye Research Institute in San Francisco, California.

YouDescribe is available online and as a free iOS app. At this time, audio description tracks can only be created through web browsers. YouDescribe can be used with or without an account for viewing videos, but connecting to a Google account is required for requesting videos and creating descriptions.


Do I have to use YouDescribe to make my videos accessible?

If users are creating their own videos, they don’t necessarily need to add a secondary audio description track to make their videos accessible for blind and low vision audiences. However, they will want to make sure that all relevant visual information is described onscreen and that someone would be able to watch the video with their eyes closed and still understand everything that is going on. Even if users choose not to add audio description, the information in this post is still a great guide for creating narration for videos aimed at audiences with vision loss.

Why add audio description to science experiments?

As a student with low vision, having access to audio description for science experiments can be incredibly helpful for the following reasons:

  • It’s helpful to have information about visual characteristics of items in the video, especially since people may not have a mental model for what these items look like
  • A lot of visual changes in science experiments are very subtle and it can be difficult to see how items change over time. I am unable to see changes such as tiny bubbles, subtle texture/color differences, or small particles moving around
  • It can be difficult to read measurements or see how much of something is being added unless that information is explicitly stated. While I can tell the difference between whether a small amount or a large amount of something is being poured, I may not be able to tell the difference between 30 milliliters and 50 milliliters
  • Some experiments involve flashing or rapidly flickering lights, which can trigger photosensitivity and cause affected viewers to look away from the screen
  • Equations displayed on the screen may be difficult to read, especially if they have lots of exponents or similar-looking numbers/letters

Related links


One of the most common questions new describers have is when to use inline description (which involves reading audio description over the video audio) or extended description (which involves pausing the video to read audio description), and what to consider choosing one type over the other. While there are some people who prefer one style over the other, here is what I prefer as someone who relies on audio description for understanding content.

When to use inline:

  • When there is limited voiceover/speaking or lots of music
  • If the necessary descriptions are short and can be quickly read in natural pauses
  • Whenever the narrator is describing movement, i.e pouring or combining

When to use extended:

  • If there is lots of description needed at the beginning for the layout of the scene
  • When a scene changes very quickly and additional description is needed
  • If there is lots of talking or voiceover content
  • When sound is an important part of the video (i.e sizzling or crackling sounds)

What to include in audio description for science experiments

Here are my recommendations for what to include in audio description for science experiments, which may vary depending on the type of experiment:

  • Names of equipment being used, i.e bunsen burner or beaker
  • Short descriptions of materials being used, such as chemical names, substances, or similar information. Visual descriptions of items that are less common can be included- while I know what a rock is, I might be interested to know what specific type of rock I’m using if I’m watching a video related to geology
  • Any appearance changes such as bubbles, color changes, expanding/shrinking
  • Items being added or removed- for example, pouring in 10 milliliters of vinegar or removing 15 milliliters of water
  • Reading any text or equations on the screen verbatim and not skipping any details
  • Descriptions of textures- is the result of the chemical reaction a thick foam?
  • Relevant movement of items onscreen, such as if a liquid spills out of the container. No need to mention items that are not in focus being moved offscreen, such as a notebook. However, feel free to mention if nothing changes after an experiment, as this can also be important information.

Related links

What not to include in audio description for science experiments

Here are my recommendations for what not to include in audio description for science experiments, which may vary depending on the type of experiment:

  • Redundant information that is already covered by narration
  • Descriptions of color names- I know what red looks like, but I’m interested to know if it is a bright red, muted red, red-orange, etc
  • Descriptions of sounds within the video- the job of audio description is to describe visual information, not auditory information
  • Definitions of terms or equipment, unless it is explicitly mentioned in the text of the video
  • Reactions to visual information such as excitement or disgust

Related links

Final thoughts

Science experiments are a lot of fun to watch for people of all ages, and can be a valuable educational tool. By adding audio description for science experiments, viewers can better understand what is happening in a video and pick up on details they would have otherwise missed. I hope that this guide for creating audio description for science experiments and science labs is helpful for others as well!

Creating Audio Description For Science Experiments With YouDescribe. Make videos of science experiments and science labs accessible for blind and low vision audiences by creating audio description for free with YouDescribe