What is the best way to deal with being on a university campus 24-7 with no outdoor smoke free zones thus being exposed to lots of second hand smoke?

Really sorry for you: that shouldn't be the case in your campus, but until this problem is rectified you may want to isolate yourself rather. Wearing a mask and changing it often, unpractical but can help, you can try the N 95 mask, or air purifying face masks, sold at amazon and other outlets. You can start a movement at your campus / check with the health-center for any kind of procedure that can isolate the smokers