S-2.1, r. 4 - Safety Code for the construction industry
3.6.3. Steel frame stairs: In addition to the requirements of section 3.6.2, skeleton steel stairs shall have temporary treads and landings:
(a) of contiguous planking extending the full width and breadth of these elements; and
(b) be securely fastened in place.
R.R.Q., 1981, c. S-2.1, r. 6, s. 3.6.3.