Pennsylvania Code
Title 34 - LABOR AND INDUSTRY
Part I - Department of Labor and Industry
Chapter 21 - LADDERS
CONSTRUCTION MATERIALS
Section 21.21 - Wood side rails
Current through Register Vol. 54, No. 38, September 21, 2024
(a) Wood side rails shall not be made from low density wood but shall be of throughly seasoned material free of any of the following defects:
(b) Cross grain in wood side rails of the different types and sizes of ladders when measured over a distance which will assure the determination of the general slope of the grain, not influenced by short, local deviations may not exceed the following:
(c) Knots shall not appear in the narrow faces of side rails.
(d) Knots in side rails shall not exceed one inch in diameter.
(e) Knots appearing in the wide faces of side rails of minimum dimensions adjacent to the edges shall not exceed in diameter 1/12 the width of the face. The size of knots in the wide faces may increase proportionately from the size allowed adjacent to the edge to 2 1/2 times that size at the center line of the wide face. Knots appearing in side rails may be larger if compensated for by additional cross section and if the strength of the piece is equivalent to or greater than the strength of a similar piece of minimum dimensions. However, no knot, for which compensation for size is allowed, shall exceed, when located adjacent to the edge of the piece, 1/6 the width of the wide face.
(f) Knots adjacent to the edges shall not appear within 1 1/2 inches, measured parallel to the length of the side rail, of the section occupied by a rung, tread, cleat or other knot.
(g) Pitch pockets not exceeding 1/8 inch wide, two inches long and 1/2 inch deep are permitted in wood side rails if not more than one appears in each four feet of length.
(h) Wood side rails shall be dressed on all sides and free from sharp edges and splinters.
(i) Wood side rails shall be made from Eastern spruce or Sitka spruce or approved equivalent. Other woods may be suitable for ladder construction if so classified in §§ 21.61-21.72 (relating to wood classification).
This section cited in 34 Pa. Code § 21.23 (relating to wood steps).