R 408.10736 Projections.

Rule 736. Projecting keys, set screws, and other projections in revolving parts exposed to contact shall be removed, made flush, or guarded. This does not apply to keys or set screws within gear or sprocket casings or other enclosures, nor to keys, set screws, or oil cups in hubs of pulleys less than 20 inches in diameter if they are within the plane of the rim of the pulley.