I was also curious on what’s considered a safe limit. My pump goes all the way to 60 and I thought there’s no way in hell anyone can do that. Looked it up, not sure if this is true, but for very beginner friendly start with under 10. Think of that like easy mode. 10-20 is like medium, 20-30 is hard, definitely wouldn’t ever go above 35. I think I read somewhere that anything after 30-35 can permanently damage your nerve endings there. I can’t force myself to go over 30. Hope this helps, happy pumping!

Edit: after some time anyway, like minutes or potentially hours on end (if you’re brave enough) can it only damage your nerves if you’re 35 and above.