Regulations shall be promulgated by the department as provided in 45 Pa.C.S. Part II (relating to publication and effectiveness of Commonwealth documents) and by the appropriate purchasing agencies for those matters contained in section 301(c) (relating to procurement responsibility). The regulations shall be subject to the act of June 25, 1982 (P.L.633, No.181), known as the Regulatory Review Act. The department may not delegate its power to promulgate regulations. No regulation may change any commitment, right or obligation of any Commonwealth agency or of a contractor under a contract in existence on the effective date of the regulation.