Thanks for humouring me purple!
To be fair, deaf scientists are often at a disadvantage compared with their hearing colleagues in terms of communication in this country.
Yes, I totally understand this!
They would need to take their own interpreter, just as if I went to a conference in Italy, I would need one because I don’t speak Italian.
And this. Though at non UK conferences I have been to (grand total of 2 admittedly, and not outside Europe) the official language of the conference has been English, with translators into the host language, or into English from the host nation language if needed. That may be unusual in my field (though it's not a particularly "anglocentric" field in my experience) but I suppose English has historically been the most widely understood language (for not entirely palatable reasons, obviously). So I recognise that I'm very privileged in being both a native English speaker, and a hearing person in that community, so I wouldn't usually need to provide an interpreter.
International sign language is a thing. Deaf people who know it can use that to communicate with signers who use different signed languages.
Aaaah! That's good! That makes sense... So people would usually use their own language, but may also have a kind of basic knowledge of international sign language to communicate with others if needed... Like my rudimentary Spanish that is used in extremis, that will usually get me what I want in a Spanish taverna, but wouldn't win any prizes for vocabulary diversity or grammatical correctness.