(a) A person employing or directing another to perform labor of any kind in the erection, repairing, altering or painting of a house, building or structure shall not furnish or erect or cause to furnished or erected for the performance of such labor scaffolding, hoists, stays, ladders or other mechanical contrivances which are unsafe, unsuitable or improper and which are not so constructed, placed and operated as to give proper protection to the life and limb of a person so employed or engaged.
(b) Scaffolding or staging swung or suspended from an overhead support or erected with stationary supports more than 20 feet from the ground or floor, except scaffolding wholly within the interior of a building and which covers the entire floor space of any room therein, shall have a safety rail of suitable material, properly bolted, secured and braced, rising at least 34 inches above the floor or main portions of such scaffolding or staging and extending along the entire length of the outside and the ends thereof, with such openings as may be necessary for the delivery of materials, and properly attached thereto, and such scaffolding or staging shall be so fastened as to prevent the same from swaying from the building or structure.