Tucson Mayor Regina Romero signed an emergency proclamation requiring face coverings in public places in Tucson for anyone over age 2. It does not have to be a store bought disposable mask (you can make your own), but it does need to cover the nose and mouth.
There are some exceptions to the proclamation. According to KVOA
When a person is in a personal office or similar space (a single room) where others are not present as long as the public does not regularly visit the room.
For any person who falls under CDC guidance for those who should not wear a face covering, including but not limited to any child under the age of two (2).
For any person who cannot wear a Face Covering because of a medical condition, mental health condition or developmental disability, or who is unable to remove the Face Covering without assistance. A person who cannot wear a Face Covering because of a medical condition is not required to produce medical documentation of the condition, provided that an employer may require such documentation from an employee in accordance with state and federal law.
For restaurant patrons while they are eating or drinking at their table or seating area.
For public safety employees and/or emergency responders, when wearing the Face Covering would interfere with or limit their ability to carry out their duties or functions; and for any person acting at the direction of a public safety employee.
In settings where it is not practicable or feasible to wear a Face Covering, such as when receiving dental services, medical treatments or while swimming.
For persons exercising outdoors, or while walking or exercising with other persons of the same household, as long as Physical Distancing from others is maintained.