All Air Force members are required to adhere to standards of neatness, cleanliness, safety, and military image to provide the appearance of a disciplined service member when wearing the uniform. AFI 36-2903 expands this requirement by stating that to present the proper military image, clothing will be neat, clean, pressed, properly fitted, in good condition, zipped, snapped, or buttoned.
When To Wear the Uniform
Military Duties. Air Force members must wear a uniform while performing normal military duties. Installation commanders may require assigned personnel to wear specific uniforms or uniform items when performing regular duties, as well as when participating in formations and ceremonies. Commanders may also prescribe the wear of optional authorized uniform items if the Air Force provides such items at no cost. Members may wear other authorized optional items at their own expense. When members perform duty at stations other than their own, they must comply with the uniform policies established at each TDY (Temporary Duty) location.
Traveling. Unless required by organizational guidance, wearing a uniform is optional when a member is departing from a military airfield on DoD aircraft or US Government commercial contract flights. Those choosing to wear civilian clothing will ensure it is neat, clean, and warm enough for in-flight operations and appropriate for the mode of travel and destination. Ripped, torn, frayed, or patched clothing, as well as tank tops, shorts, sandals, and any garments that are revealing or contain obscene, profane, or lewd words or drawings are examples of inappropriate attire. When traveling in a deployed status or between installations due to deployment, the BDU is also acceptable. When departing from or arriving at commercial airports, members may wear either the service uniform with tie or tab or civilian attire. When traveling in foreign countries, members must consult the DoD Foreign Clearance Guide
Additional Restrictions. Air Force members are also restricted from wearing the uniform when uniform items do not meet Air Force specifications; when participating in public speeches, interviews, picket lines, marches or rallies, or any public demonstration when the Air Force sanction of the cause for which the activity is conducted may be implied; to further political activities; for private employment or commercial interests; when working in an off-duty civilian capacity, if it would discredit the Armed Forces; or when in civilian attire (for example, grade insignia, cap devices, badges, insignia, distinctive buttons, etc.).
Personal Grooming Standards
Hair. Hair will be clean, well groomed, and neat. If dyed, hair will look natural. Hair will not contain an excessive amount of grooming aids, touch the eyebrows when groomed, or protrude below the front band of properly worn headgear. EXCEPTION: Hair may be visible in front of the womens flight cap.
Men. Mens hair must have a tapered appearance on both sides and back, both with and without headgear. A tapered appearance is one that, when viewed from any angle, outlines the individuals hair so that it conforms to the shape of the head, curving inward to the natural termination point. The block cut is permitted with tapered appearance. It will not be worn in an extreme or fad style or in such a way that it exceeds length or bulk standards or violates safety requirements. Hair will not touch the ears; only closely cut or shaved hair on the back of the neck may touch the collar. It will not exceed 1 1/4 inches in bulk, regardless of length, and not exceed 1/4 inch at the natural termination point. Mens hair will not contain or have any visible foreign items attached to it.
Women. Women must style their hair to present a professional appearance. Hair will not be worn in an extreme or fad style or violate safety requirements. It cannot extend below the bottom edge of the collar. Hairstyles must allow proper wear of headgear and will not exceed 3 inches in bulk. Women may wear plain and conservative pins, combs, headbands, elastic bands, and barrettes that are similar to their hair color to keep their hair in place. Hair ornaments such as ribbons or jeweled pins are not allowed.
Above information derived from AFPAM36-2241V1, PME Study Guide

