US Dept of Labor

Occupational Safety & Health AdministrationWe Can Help

Regulations (Standards - 29 CFR) - Table of Contents
• Part Number: 1919
• Part Title: Gear Certification
• Subpart: H
• Subpart Title: Certification of Shore-Based Material Handling Devices
• Standard Number: 1919.73
• Title: Unit proof test and examination of derricks.
• GPO Source: e-CFR


Unit proof tests of derricks shall be carried out at the same times as are specified in 1919.71(a) for cranes.


Unit proof load tests and safe working load ratings shall be based on the design load ratings at the ranges of boom angles or operating radii. Unit proof loads shall exceed the safe working load as follows:

  Safe working load   |     Proof Load
Up to 20 tons..........| 25 percent in excess.
20 - 50 tons...........|  5 tons in excess.
Over 50 tons...........| 10 percent in excess.

Proof loads shall be applied at the designed maximum and minimum boom angles or radii, or, if this is impracticable, as close to these as practicable. The angles or radii of test shall be stated in the certificate of test. Proof loads shall be swung as far as possible in both directions. The weight of all auxiliary handling devices shall be considered a part of the load.


After satisfactory completion of a unit proof load test, the derrick and all component parts thereof shall be carefully examined in accordance with the requirements of 1919.71(d), as far as applicable.

Next Standard (1919.74)

Regulations (Standards - 29 CFR) - Table of Contents

Thank You for Visiting Our Website

You are exiting the Department of Labor's Web server.

The Department of Labor does not endorse, takes no responsibility for, and exercises no control over the linked organization or its views, or contents, nor does it vouch for the accuracy or accessibility of the information contained on the destination server. The Department of Labor also cannot authorize the use of copyrighted materials contained in linked Web sites. Users must request such authorization from the sponsor of the linked Web site. Thank you for visiting our site. Please click the button below to continue.