Good question sobko I am looking forward to seeing some comments.

I would like to know if anyone has tried using a combination oxygen-nitrogen theropy as they have i scuba diving tanks,air is pure without pollutants as cleans lungs?

Don't smoke, Don't breathe in smoke from any source. Don't use fossil fuels in your home without really good ventilation. Don't breathe in polluted air. Those are all the prevention we need.