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Subchapter 7. General Industry Safety Orders
Group 4. General Mobile Equipment and Auxiliaries
Article 23. Mobile Ladder Stands and Scaffolds (Towers)

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§3627. Mobile Ladder Stands.

(a) Units shall comply with applicable requirements of Section 3622.

(b) The minimum base width shall conform to Section 3622(f). The minimum length of the base section shall be the total length of combined steps and top assembly, measured horizontally, plus 5/8-inch per step of rise.

(c) Steps shall be uniformly spaced, and sloped, with a rise of not less than 9 inches, nor more than 10 inches, and a depth of not less than seven (7) inches nor more than 10 inches including the top tread. The slope of the steps section shall be a minimum of 55 degrees and a maximum of 60 degrees measured from the horizontal.

(d) Units having steps with four or more risers shall be equipped with handrails.

(e) Handrails shall be a minimum of 30 inches high. Measurements shall be taken from the upper surface of the top rail to the surface of the tread in line with the face of the riser below the tread.

(f) The design working load stipulated in Section 3622(b)(1) shall be applied uniformly to a 3 1/2-inch wide area front to back at the center of the width span with a safety factor of 4.

(g) Mobile ladder stands with a top step height of 48 inches or greater from the floor or level below shall have guardrail protection that meets the requirements of Sections 3209 and 3210.

(h) Mobile ladder stands with a top step height greater than 30 inches but less than 48 inches shall have a guardrail at least 30 inches (+ 1 inch) in height.

NOTE: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.


1. Amendment of subsection (f) filed 12-19-78; effective thirtieth day thereafter (Register 79, No. 1).

2. Amendment filed 10-12-84; effective thirtieth day thereafter (Register 84, No. 41).

3. New subsections (g) and (h) filed 12-2-86; effective thirtieth day thereafter (Register 86, No. 49).

4. Change without regulatory effect amending subsection (b) filed 4-8-92 pursuant to section 100, title 1, California Code of Regulations (Register 92, No. 15).

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