Sustainable Tucson Main page. Sustainable Tucson Index Index of pages for Sustainable Tucson. Sustainable Tucson Notespage If you are not sure where to add your input, please put your notes here. Priority I - Air: Essential for survival much beyond 3 minutes. If you can't breathe, you are not going to be concerned about much else. Each minute we breathe about 2 gallons of air, which is close to 3,000 gallons per day. Air is made up of 78% nitrogen 21% oxygen, under 1% carbon dioxide, and trace amounts of other gases. Things to consider: Let elected officials know how you feel about air pollution. .