Scaffold posts and frames shall be erected and maintained vertical and plumb and vertically braced in both directions to prevent swaying and displacement. Plumbness shall be checked using a spirit level, plumb bob, or by using vertical lines on an adjacent building or structure.

When uplift or tension loads may occur in posts or frames, they shall be locked together by pins, bolted or pinned spigots, end to end coupler scaffold, or equivalent means able to carry the tension loads.

Supported scaffolds with a height to the uppermost planked level that is over four times the minimum base dimension shall be restrained from tipping by ties, guys, outrigger frames, or equivalent means. Upper sections of a stepped scaffold shall not have a height over four times the width of the scaffold at the base of that section, unless ties or guys are properly installed to ensure stability.

Where the means of access to the working platform is outside the scaffold structure, due consideration shall be given to the effect of such means of access on the stability of the scaffold.