Section 106. The department shall, from time to time, ascertain the degree of purity that can reasonably be required in gas made and supplied by persons engaged in the manufacture or sale of gas, and shall report to the general court when it deems any change in the law relative thereto is desirable, and may from time to time, after notice and a public hearing, establish rules and regulations consistent with law, governing the quality of gas supplied by persons or municipalities subject to this chapter. Such rules and regulations shall be enforced in the manner provided in section seventy-nine.