Potable
water outlets with hose attachments, other than water
heater drains, boiler drains, and clothes washer connections,
shall be protected by a nonremovable hose bibb-type
backflow preventer, a nonremovable hose bibb-type
vacuum breaker, or by an atmospheric vacuum breaker
installed not less than 6 inches (152 mm) above the highest
point of usage located on the discharge side of the last
valve. In climates where freezing temperatures occur, a
listed self-draining frost-proof hose bibb with an integral
backflow preventer or vacuum breaker shall be used.