How do you sign phenolphthalein?

So every other morning as I come into work I pass by this auditorium with a chem class underway. Poor bastards get started before 8:00 am as far as I can tell. The interesting thing about this class though is that as I pass by I can see the prof and seated up front with him is a woman doing sign language for at least one of the students. This isn't anything that is particularly uncommon to any university setting, there are plenty of students with disabilities that attend university and a number of resources are present to help them in their studies.

What have begun to ponder is just how hard it must be to do sign language for a science based class. I'll admit I really don't know much about sign language, I know that there is an alphabet, as well as a vocabulary of compete words, but how extensive is it? Hell it doesn't even matter how extensive your vocabulary is, once you get into a scientific field you start to come across some word that, well to be frank, have been made up from other words, like "kosmotropic" (meaning inducing or promoting the hydrogen bonding structure of water). So how on earth do those signing words to the deaf deal with those terms, or even the names of compounds, like phenolphthalein (which I frequently spell wrong). After all I'm fully bilingual (French and English) yet I have no clue what half the element names are in French, where names as basic as nitrogen become azote.

But I guess that's part of the nature of any specialized field becomes an education in a new language. All specializations use their own complex languages to simplify communication within the field. Be it medicine, music, law or physics, there are words used, like kosmotropic, which mean a great deal to those that can understand them and nothing to the rest of the world.

So I guess the biggest challenge to learning chemistry through sign language is that the translation of the words from sounds to gestures has got to be difficult. I wonder if the person signing has also been taught chemistry? If not it certainly would be a good way to go about learning new subjects.