Answer:
There are a lot of parts to this question, so let´s begin slowly and with small explanations.
1. The ASA, or American Sociological Association, is an association that was started in 1905 and it basically dedicates to the furthering of the sociological profession in all of its different aspects, but most importantly, research, as one of its fundamental aspects. Because of the importance of sociological research, the questions that it helps to unravel, and the fact that sociology focuses on people, how they interact and behave, the ASA established a Code of Ethics, with 5 main principles that are set to regulate and frame all sociological research, at least in the U.S. It is highly detailed because of sociology´s subjects of research: human beings, their societies, and their interactions.
2. Because of the purposes of sociological research, there may be studies performed that may cause harm. For example studies in which a specific response is desired from the participants, and therefore certain limitations are crossed: human rights, personal boundaries, societal boundaries. Many sociological research, for example was extracted from Germany and Russia during the era of the Second World War, but the boundaries crossed were enormous here, as the responses were sought and desired. There have been cases in which sociologists have crossed those human boundaries and that is why protocols, codes of ethics and conduct, among other legal limitations, had to be taken.
6. I think the answer to this question is pretty subjective and it depends on the personal position and views of each of us. In my case, if the outcome could be to help other people, even at the cost of my own welfare, I would do it. But for me to do that, the outcome would really have to be meaningful, like discovering a cure for cancer, or diabetes. If the potential harm to me, and the potential for actually discovering useful things for others were unbalanced, meaning, the harm to me would not give a good result to research in the end, then no, I would definitely not do it.