Michigan Administrative Code
Department - Labor and Economic Opportunity
MIOSHA
General Industry and Construction Safety and Occupational Health Standards
Construction Safety and Health Standard
Part 8 - HANDLING AND STORAGE OF MATERIALS
Section R. 408.40840 - Shackles and hooks safe working loads

(1) The manufacturers recommendations shall be followed in determining the safe working loads of the various sizes and types of specific and identifiable hooks. All hooks for which manufacturers recommendations are not available shall be tested to twice the intended safe working load before they are initially put into use. The employer shall maintain a record of the dates and results of such tests.

(2) Employers shall not use shackles with loads in excess of the rated capacities, such as working load limits, indicated on the shackle by permanently affixed and legible identification markings prescribed by the manufacturer.