65 ILCS 5/10-2.1-16

In order to prevent a stoppage of public business, to meet extraordinary exigencies, or to prevent material impairment of either the police or fire department, the board may make temporary appointments, to remain in force until regular appointments may be made under the provisions of this Division 2.1, but never to exceed 60 days. No temporary appointment of any one person shall be made more than twice in any calendar year.