Resource Center > Essential Guide to Closed Captions
Closed Captions in International Accessibility Laws
Updated July 24, 2023
Key standards and guidelines
The main standardisation effort in this area is the Web Content Accessibility Guidelines (WCAG) by the World Wide Web Consortium (W3C). WCAG is widely regarded as a best practice for web accessibility and has been adopted into a variety of international legislation. WCAG clearly states the key aspects that SDH Captions should meet, but does not include technical requirements or quality metrics.
There are also a number of international initiatives in this area. Here are some of the most important ones:
- The U.S. regulations for closed captions includes the 21st Century Communications and Video Accessibility Act (CVAA), FCC rulings and Americans with Disabilities Act. They have been developed and mandated for certain types of online video (albeit limited) through legislation and case law, parallel to WCAG. They also have had a big impact on international best practices and ongoing standardisation efforts.
- Also in the U.S., the Described and Captioned Media Program (DCMP) has developed Captioning Key, a set of detailed SDH caption guidelines focused on accessibility of educational and training materials.
- One of the oldest and most detailed set of guidelines for SDH captions are the BBC subtitling guidelines by the British public broadcasting company. These guidelines differ from Captioning Key in certain aspects, in part because they cover captioning not only for Web video but also for television.
As mentioned, there are a number of standards and guidelines that exist for captions created for the hearing impaired. However, there is still a big difference between captions that are added to Video on-Demand and captions generated during live streams.
There is a consensus on what constitutes ‘good’ SDH captions, although requirements and guidelines may vary to some extent depending on the region, sector and type of content. To meet the accessibility requirements of WCAG Level A, which is the lowest level, SDH captions should be provided for pre-recorded audio content in synchronized media.
Organizations such as the BBC, DCMP, and the Federal Communications Commission (FCC) in the United States have established specific guidelines and best practices for SDH subtitling. These guidelines may differ in aspects such as text placement, timing, style, and presentation of non-verbal information.
There are several companies and professionals operating in this field. They vary in size and expertise. It is advisable to choose a provider with experience in SDH subtitling and familiarity with the relevant standards and guidelines.
SDH captions are much less required for live streams than they are for pre-recorded videos. The WCAG requires them as part of level AA, which is already a more advanced degree of accessibility. Nevertheless, level AA is required by a number of national and supranational regulations, for specific content and mainly in the public sector.
As for best practices and requirements, there is less clarity. Some guidelines, such as the BBC’s, have a short section on live captions. It is generally assumed that most requirements for pre-recorded content should also be pursued for live streams. However, there is less consensus on how this should be done and what conditions should at least be met.
For live SDH subtitling, there are far fewer providers. Generally, this is done manually using a stenotype keyboard, or through respeaking software that uses AI to generate the captions.
For standard (speech-only) captions there are few, if any, initiatives for standardisation. The legal obligations, which exist for SDH subtitling, don’t apply here. For some aspects of standard captions, the same guidelines as for SDH subtitles can be followed, bearing in mind that their purpose is different.
For offline captions, the absence of standards mainly makes it difficult to compare the quality of services or captioners. But there are sufficient providers in this field. By conducting thorough research, checking references, and requesting trials, you can select a provider that fulfills your specific needs.
For standard captions in live streams, the disparities between captions from different providers are the most pronounced. This applies to the accuracy of the captions, their readability, and the way they are displayed. The way live captions are generated can also vary: using human captioners, AI, or a combination of both. Since there is no quality standard, it is difficult to assess exactly what is promised and what is delivered.