There shall be on duty at all times that the operation of a billiard center, bowling alley, golf course, mechanical or electronic amusement devices, public skating rink, theater or game room is open to the public an adult operator or manager who understands the operation of all equipment used on the premises. It shall be the duty of the licensee and his manager to remain on the premises at all times and enforce the provisions of subsection 3-2-10A of this chapter. (2006 Code)