I was visiting a bigger city and went to a bathhouse. I think I was pretty safe, only touched/hand job/body contact and received oral from one other guy who claimed to be on prep. No anal, and I did not give oral. 

My concern is I was in a dark steam room, and while standing one random man ejaculated on my leg and feet, I did not know this would happen or who it was. I felt uncomfortable with this and went to go wash it off within a 1-2ish minutes of it happening. 

Somehow it happened again and this time just on my foot from another man in the same steam room, so I avoided the steam room and left. I might have spent a little longer before cleaning this time. 

I have an aversion to semen and a fear of HIV. When I first entered the bath house, I got in the hot tub and kind of scratched/exfoliated my legs with my finger nails. This could have created openings that the hiv from the semen could enter from? 

I have heard that once hiv enters the air it becomes ineffective, but this air was warm and moist plus the semen landed directly on my legs. So I worry that it’s not ineffected by the air. 

Once I got home a few hours later, I rubbed rubbing alcohol to see if it stings and it didn’t, so maybe I didn’t have any cuts. I don’t see any, it would be very superficial if I had any. 

I take PrEP on demand, and took 2 pills about 2-3 hours before this happened. And plan to complete my 2 day following dosage. I don’t engage in anal, but have it for occasions like this where accidents could happen. 

Occasional questions can be answered accurately just from the title the user selects. Having read nothing else, I can confidently say there is little or no risk for HIV or any STI from semen contacting skin cuts, scratches, etc.

Now I have read the full question. You describe a very safe exposure -- congratulations on limiting your activities to the events described. And to expand on my opening comments, nobody in the world is likely to have caught HIV from semen (even from infected persons) contacting cuts, nicks or scratches on the skin. Exposure of infected fluids to air does not "immediately" kill the virus or make it non-infective; that happens only as the fluid dries. But the biological reason for lack of transmission in this situation doesn't matter:  since it has never been known to happen, the particular reason really doesn't mater, right? On top of that, it now appears the semen didn't come into contact with any cuts on your skin anyway.

I would not have recommended PrEP in this situation. It won't hurt anything, but really wasn't necessary. (In fact, if you never engage in anal sex, either top or bottom, I see no need for you ever to take PrEP. But that's between you and your doctor.)

I hope these comments are helpful. Let me know if anything isn't clear.

HHH, MD

It’s good to know I didn’t need the PrEP, as I accidentally delayed by second on-demand prep dosage by approx 1 hour. I’m going to finish my dosage tomorrow and move on. For future reference, would short delays like this be a big issue? 

Re PrEP, once started it's general best to continue until the full dose has been taken -- although of course optional in this situation. In any case, an hour's delay (even several hours) in the second or third dose makes no difference in effectiveness.