53 Pa. Stat. § 23447
Positions in the competitive class may be filled without competition, only as follows:--
First.--Whenever there are urgent reasons for filling a vacancy in any position in the competitive class, and there is no list of persons eligible for appointment after a competitive examination, the appointing officer may nominate a person to the civil service commission for non-competitive examination; and if such nominee shall be certified by the said commission as qualified, after such noncompetitive examination, he may be appointed provisionally, to fill such vacancy until a selection and appointment can be made after competitive examination, in the manner prescribed in section fourteen; but such provisional appointment shall not continue for a longer period than three months, nor shall successive provisional appointments be made to the same position, under this provision.
Second.--In case of a vacancy in a position in the competitive class, where peculiar and exceptional qualifications of a scientific, professional, or educational character are required, and upon satisfactory evidence that, for specified reasons, competition in such special case is impracticable, and that the position can be best filled by the selection of some designated person of high and recognized attainments in such qualities, the said commission may suspend the provisions of the statute requiring competition in such case; but each such suspension shall relate to only a single appointment, and shall not be general in its application to the position, and all such cases of suspension shall be reported in detail in the annual reports of the commission, with the reasons for the same.
53 P.S. § 23447