It mostly depends on your arrangement with your T. For the most part, if they are aware of the fact that you may SI, and are treating you for this, it will not be reported to anyone else. However, depending on the agency/practice that you work with, they might say you are required to be looked at by a medical doctor to make sure you are physically okay. This is really just to cover their butt in case you are sitting there with a serious injury covered up. If something were to happen, they could get blamed for not doing anything. But you should not be in a position where you are in danger of being committed just for non-suicidal SI. It is different for under-age people, but it is fairly difficult to committ a non-suicidal adult in the U.S. in most cases.