S-2.1, r. 4 - Safety Code for the construction industry
(1) Two stringers located at the same level can only be joined at right angles with an upright.
(2) Any stringer shall be in a horizontal position.
(3) Any stringer shall be sufficiently long to be sustained by at least 3 uprights.
R.R.Q., 1981, c. S-2.1, r. 6, s. 3.9.6.