In the case of a vacancy in the office of superintendent of police, assistant superintendent of police, inspector of police, or fire chief or chief fire inspector or equivalent official, the county commissioners may nominate a person to the commission. It shall thereupon become the duty of the commission to subject such person to a noncompetitive examination, and if such person shall be certified by the commission as qualified, he may then be appointed to such position, and thereafter shall be subject to all the provisions of this article.
16 P.S. § 4513