The OSHA Standard for portable ladders contains specific requirements designed to ensure worker safety:

Loads

• Self-supporting (foldout) and non-self-supporting (leaning) portable ladders must be able to support at least four times the maximum intended load, except extra-heavy-duty metal or plastic ladders, which must be able to sustain 3.3 times the maximum intended load.

Angle

• Non-self-supporting ladders, which must lean against a wall or other support, are to be positioned at such an angle that the horizontal distance from the top support to the foot of the ladder is about ¹⁄₄ the working length of the ladder.
• In the case of job-made wooden ladders, that angle should equal about ¹⁄₈ the working length. This minimizes the strain of the load on ladder joints that may not be as strong as on commercially manufactured ladders.

Rungs

• Ladder rungs, cleats, or steps must be parallel, level, and uniformly spaced when the ladder is in position for use. Rungs must be spaced between 10″-14″ inches apart.
• For extension trestle ladders, the spacing must be 8″-18″ inches for the base, and 6″-12″ inches on the extension section.
• Rungs must be so shaped that an employee’s foot cannot slide off, and must be skid-resistant.

Slipping

• Ladders are to be kept free of oil, grease, wet paint, and other slipping hazards.
• Wood ladders must not be coated with any opaque covering, except identification or warning labels on one face only of a side rail.

Other Requirements

• Foldout or stepladders must have a metal spreader or locking device to hold the front and back sections in an open position when in use.
• When two or more ladders are used to reach a work area, they must be offset with a landing or platform between the ladders.
• The area around the top and bottom of ladder must be kept clear.
• Ladders must not be tied or fastened together to provide longer sections, unless they are specifically designed for such use.
• Never use a ladder for any purpose other than the one for which it was designed.