Honestly I think many deaf people are
afraid of blind people, because they feel they cannot communicate with them. If the blind person knew ASL and could receive tactile sign, they would be less afraid.
But really I don't know how well this would work. Interpreting is not just about hearing, in many situations sight is required too, especially for prep work. Some examples of situations:
- Medical appointment - you need to be able to see what the doctor is doing to the patient in order to interpret. Or if they point to a chart, you would want to be able to reference what they're pointing to.
- Corporate meeting - these go around the room very fast, people speak over each other all the time, and you need to be able to visually identify who is speaking so you can point at them. Pointing in their direction is sometimes good enough, but sometimes you need to be specific. If you can't see who's speaking, you might have a hard time with this.
- Anything involving a powerpoint - Lots of information that an interpreter needs to know is shown on powerpoint displays. Name spellings, organization names, key words, etc. You may not always get a copy of the powerpoint slides beforehand. This is why the Interpreter Mirror was invented - so terps could see what was on powerpoint slides or blackboards without having to turn around all the time. (Unfortunately it never took off, I only used one once.)
- Computer training - sometimes you will get to see either the instructor's screen or the client's screen. This is VERY helpful because then when the instructor says "now click on the box that says start" you can use spatial parts of ASL to clarify which box is intended.
These are just a few examples of when sight would be needed. However, there are also many situations when perfect sight would NOT be needed. A lecture with no charts being shown, one-on-one interactions (most of the time), etc.
So I think it is
possible for a hearing blind person to be a terp, but you would have to pick and choose assignments carefully. Mentoring is a good way to see a variety of assignments and determine if you could work in them - you will get to observe an experienced interpreter and figure out if they need to see in any given situation.