71 Pa. Stat. § 1463
The Commission of Public Welfare shall consist of nine members, three of whom, as ex officio members, shall be the Commissioner of Public Welfare, the Commissioner of Labor and Industry, and the Commissioner of Health, and six of whom shall be appointed by the Governor, by and with the advice and consent of the Senate. Before the first day of September, one thousand nine hundred and twenty-one, the Governor shall appoint three of the said six members of the commission to serve for a period of two years, and three to serve for a period of four years. Thereafter all of said six members shall be appointed for a term of four years. The members of the commission shall serve without compensation, but shall be allowed the expenses necessarily incurred in the performance of their duties.
71 P.S. § 1463