Work on accessibility in ITU-T SG 16 has its base in Question 26, Accessibility to Multimedia.

The work is done in close co-operation with many other groups and in many cases focuses on integrating sections on accessibility in Recommendations. A large part of Q.26’s work aims at including procedures for the Total Conversation concept for conversation in Real-time Text, Video and Voice as an accessible superset of video telephony, text telephony and voice telephony.

The following ITU-T Recommendations are a result of SG 16’s work:

• V.18 harmonization of text telephony
• V.151 Procedures for the end-to-end connection of analogue PSTN text telephones over an IP network utilizing text relay
• T.140 the general presentation protocol for text conversation
• T.134 text conversation in the T.120 data conferencing environment
• H.323 Annex G for text conversation in H.323 packet multimedia environment
• H.248.2 gateway procedures between Text Telephony in PSTN and real-time text in IP and other networks
• H Series Supplement 1 Requirements on video communication for sign language and lip reading 
• Telecommunication Accessibility Checklist for standards writers
• F.790 Telecommunications accessibility guidelines for older persons and persons with disabilities

The following are Recommendations in which sections on accessibility have been integrated:

• Sections on accessibility were included in NGN R1 Scope Y.2000SerSup1
• Definition in F.703 of Total Conversation and Text Telephony services, offering real-time text, video and audio communication
• Definition of the real-time conversational text medium in F.700
• Inclusion in H.320 of real-time text conversation in ISDN multimedia
• Section on transport of real-time text in ISDN multimedia environments in H.224
• Sections on modem negotiation for text telephony in V.8
• Sections in V.8 bis on modem negotiation for text telephony
• Sections in V.250 on control of V.18 modems
• Inclusion in H.324 of real time text conversation in circuit switched multimedia
• Section in H.245 for handling real-time text connections in H.324 and H.323 multimedia environments
• Inclusion in T.120 of real-time text in data conferencing
• Section in T.124 for handling real-time text sessions in the T.120 environment
• Section in G.168 for testing of echo cancellation in calls with text telephony
• Section in F.724 for accessible media additions in service description and requirements for video telephony services over IP networks
• Section in F.733 for accessible media additions in multimedia conference services over IP
• Section in F.742 for accessible media additions in service description and requirements for distance learning services
• Section in F.741 for accessible media additions in service description and requirements for audiovisual on demand services
• Inclusion in V.152 of text telephony considerations in voice band data gateway procedures