110 ILCS 70/36n

Where there are no names on the eligible register and it is impractical to give an immediate examination, applicants may be employed provisionally but such employment shall continue only until the person provisionally employed successfully passes an examination or until a name or names are placed upon the appropriate eligible register. Before any examination is given in this classification, the person provisionally employed shall have notice of the examination and shall have an opportunity to take the examination.