I'm thinking about conducting a research at a specific division of the university from which I received my PhD. The problem is that I don't work there, I'm just part of their alumni. I work at a different university. So, basically, this would be an independent study. My question is, given that this is not a dissertation proposal, can I simply complete the IRB form as an independent researcher? Or do I have to write a whole proposal? I know each university is different, but can someone give me an idea of how this works? I'm new to this idea. Thank you.
Some universities offer their alumni access to resources (and perhaps their old affiliated email address). If your university offers this to you, you can certainly take them up on it.
You are asking for more than just access to resources, you are asking for IRB approval (presumably) to conduct a study involving people/animals. This would involve the university's legal department, and some other researchers reading through your plan. Even if you agree to pay for the experiments out of pocket (I'm going ahead and assuming you're not asking IRB approval to dissect rats, because if that's what you're planning I hope you understand that the university won't endorse it), you are asking for the university's legal endorsement of your research activity, which is not be something they'd be willing to extend to someone not officially affiliated with them.
So the short answer is - the university is not likely at all to endorse your IRB (unless it operates in a vastly different way from most places I know).
If you have a good idea which you want to push forward, why not seek employment/studies in a university? Seems like you're ready to conduct research, seems like it might be easier, no?