22. The opening for the curtain in every theatre shall be provided with a curtain of incombustible material, approved of by the inspector, and sliding at each end in grooves solidly fixed in brick walls, and entering into such grooves at least one hundred and fifty millimetres on both sides. This curtain shall be raised at the beginning and lowered at the end of each performance. It shall also be worked by means of approved appliances.
R. S. 1964, c. 149, s. 22; 1977, c. 60, s. 30.