(1) General requirements.
(a) The use of ladders with broken or missing rungs or steps, broken or split side rails, or other faulty or defective construction is prohibited. When ladders with such defects are discovered, they must immediately be withdrawn from service. Inspection of metal ladders must include checking for corrosion of interiors of open end, hollow rungs.
(b) When sections of ladders are spliced, the ends must be abutted, and not fewer than 2 cleats must be securely nailed or bolted to each rail. The combined cross sectional area of the cleats must not be less than the cross sectional area of the side rail. The dimensions of side rails for their total length must be those specified in (2) or (3) of this section.
(c) Portable ladders must be lashed, blocked or otherwise secured to prevent their being displaced. The side rails of ladders used for access to any level must extend not less than 36 inches above that level. When this is not practical, grab rails which will provide a secure grip for an employee moving to or from the point of access must be installed.
(d) Portable metal ladders must be of strength equivalent to that of wood ladders. Manufactured portable metal ladders provided by you must be in accordance with the provisions of the United States of America Standard Safety Code for Portable Metal Ladders, A14.2-1972.
(e) Portable metal ladders must not be used near electrical conductors nor for electric arc welding operations.
(f) Manufactured portable wood ladders provided by the employer must be in accordance with the provisions of the United States of America Standard Safety Code for Portable Wood Ladders, A-14.1-1968.
(2) Construction of portable wood cleated ladders up to 30 feet in length.
(a) Wood side rails must be made from west coast hemlock, eastern spruce, Sitka spruce, or wood of equivalent strength. Material must be seasoned, straight-grained wood, and free from shakes, checks, decay or other defects which will impair its strength. The use of low density woods is prohibited.
(b) Side rails must be dressed on all sides, and kept free of splinters.
(c) All knots must be sound and hard. The use of material containing loose knots is prohibited. Knots must not appear on the narrow face of the rail and, when in the side face, must be not more than 1/2 inch in diameter or within 1/2 inch of the edge of the rail or nearer than 3 inches to a tread or rung.
(d) Pitch pockets not exceeding 1/8 inch in width, 2 inches in length and 1/2 inch in depth are permissible in wood side rails, provided that not more than one such pocket appears in each 4 feet of length.
(e) The width between side rails at the base must not be less than 11 1/2 inches for ladders 10 feet or less in length. For longer ladders, this width must be increased at least 1/4 inch for each additional 2 feet in length.
(f) Side rails must be at least 1 5/8 x 3 5/8 inches in cross section.
(g) Cleats (meaning rungs rectangular in cross section with the wide dimension parallel to the rails) must be of the material used for side rails, straight-grained and free from knots. Cleats must be mortised into the edges of the side rails 1/2 inch, or filler blocks must be used on the rails between the cleats. The cleats must be secured to each rail with three 10d common wire nails or fastened with through bolts or other fasteners of equivalent strength. Cleats must be uniformly spaced not more than 12 inches apart.
(h) Cleats 20 inches or less in length must be at least 25/32 x 3 inches in cross section. Cleats over 20 inches but not more than 30 inches in length must be at least 25/32 x 3 3/4 inches in cross section.
(3) Construction of portable wood cleated ladders from 30 to 60 feet in length. Ladders from 30 to 60 feet in length must be in accordance with the specifications of (2) of this section with the following exceptions:
(a) Rails must not be less than 2 x 6 inch lumber.
(b) Cleats must not be less than 1 x 4 inch lumber.
(c) Cleats must be nailed to each rail with five 10d common wire nails or fastened with through bolts or other fastenings of equivalent strength.
[Statutory Authority: RCW
49.17.010,
49.17.040,
49.17.050, and
49.17.060. WSR 18-04-096, § 296-304-05003, filed 2/6/18, effective 3/9/18; WSR 17-18-075, § 296-304-05003, filed 9/5/17, effective 10/6/17; WSR 07-03-163, § 296-304-05003, filed 1/24/07, effective 4/1/07; WSR 03-04-099, § 296-304-05003, filed 2/4/03, effective 8/1/03; Order 74-25, § 296-304-05003, filed 5/7/74.]