California Code of Regulations
Title 8 - Industrial Relations
Division 1 - Department of Industrial Relations
Chapter 4 - Division of Industrial Safety
Subchapter 4 - Construction Safety Orders
Article 14 - Construction Hoists
Section 1605.20 - Capacity Statement and Design

(a) All material hoist towers, masts, etc., shall be substantially constructed and of such design that maximum intended loads will not stress any members beyond safe limits established by applicable engineering formulas.

(b) The design shall also provide ample strength for loads imposed by the use of booms attached to a tower or mast. Where auxiliary equipment or other load-bearing devices, in addition to that of the loaded platform or bucket, is supported by the tower, the tower shall be built to withstand these additional loads and stresses safely. The rated load, specified by the manufacturer, shall not be exceeded.