(a) A service employee is an employee, other than a food service worker or fast food employee, who customarily receives tips at or above the tip threshold rate listed in section 146-1.3(a) of this Part.

(b) A non-service employee is any employee other than a service employee or a food service worker.

(c) Classification as a service employee or as a non-service employee shall be on a weekly basis except that an employee may not be classified as a service employee on any day in which she or he has been assigned to work at an occupation in which tips are not customarily received for two hours or more or for more than 20 percent of her or his shift, whichever is less.

(d) The employer shall have the burden of proof that an employee receives sufficient tips to be classified as a service employee.