Vocal Accessibility Part 1: What is PAS 901:2025?

The Web Content Accessibility Guidelines (WCAG) are the leading international standard for digital accessibility, developed by the World Wide Web Consortium. Version 2.2 is the latest version, published as a recommendation in 2023, and it covers almost all disabilities to varying degrees, including vision, hearing, mobility/motor and cognitive/specific learning disabilities. The one disability it makes no mention of is speech. It just doesn’t cover things like stammers/stutters and other impairments in this category. Which is a big omission.

It is in this context that PAS 901:2025 Vocal accessibility in system design. Code of practice was published by the British Standards Institute, in 2025. This post covers the background to the Code of Practice.

Where did it come from?

Between 2018 and 2025, the Helen Hamlyn Centre for Design, at the Royal College of Art and Tata Consultancy Services undertook research to, in their words, “better understand vocal interactions with technology and develop a set of accessibility guidelines for designers and technologists.”

Tata and the Helen Hamlyn Centre became the lead sponsors of PAS 90:2025, working with the other partners — Axelrod Access for All, Google, the Indian Institute of Technology, Microsoft, Polyloop (now, Whitelabel.ai), Special Projects, University College London and University of York.

Who benefits?

PAS 901:2025 is designed to benefit many groups, including:

• Disabled and neurodivergent people
• Older users
• People with developmental speech disfluency, developmental verbal dyspraxia, cluttering, stammers/ stutters
• Tourette’s, Tourettism, vocal tics
• People with acquired speech disfluency, aphasia, verbal apraxia, dysarthria, people who have had strokes, Parkinson’s, cerebral palsy, motor neurone disease(s), brain injuries,
• Non-verbal
• Non-native speakers

Technologies covered

That is the who. And, here is an incomplete list of the types of software and hardware that are covered:

• Automated telephony systems,
• Smart speakers,
• Internet (Web) of Things – for example, smart connected appliances,
• Speech-enabled chat-bots,
• Speech recognition software on desktop, tablet and mobile,
  • Includes operating system, assistive technologies ….
  • Speech-enabled (mobile) apps.
• Voice navigation systems, for example in cars,
• … Anything else?

These technologies are covered both in the context of design and production by vendors, and procurement and deployment by third-parties.

This concludes our introduction to PAS 901:2025.