Design of Support Systems, Shield Systems, and Other Protective Systems

The employer must select and construct the designs of support systems, shield systems, and other protective systems in accordance with one of the following four options:

Option 1: Designs Using Appendices A, C, and D

• Designs for timber shoring in trenches must be determined in accordance with the conditions and requirements set forth in Appendices A and C to subpart P.
• Designs for aluminum hydraulic shoring must be in accordance with option 2 of this section, but if the manufacturer's tabulated data cannot be used, designs must be in accordance with Appendix D.

Option 2: Designs Using the Manufacturer's Tabulated Data

Designs of support systems, shield systems, or other protective systems that are drawn from a manufacturer's tabulated data must be in accordance with all specifications, recommendations, and limitations issued or made by the manufacturer.

• Deviation from the specifications, recommendations, and limitations issued or made by the manufacturer must only be allowed after the manufacturer issues specific written approval.
• The manufacturer's specifications, recommendations, and limitations, and the manufacturer's approval to deviate from the specifications, recommendations, and limitations must be in written form at the jobsite during construction of the protective system. After that time, this data may be stored off the jobsite, but a copy must be made available to OSHA on request.

Option 3: Designs Using Other Tabulated Data

Designs of support systems, shield systems, or other protective systems must be selected from and be in accordance with tabulated data, such as tables and charts.

The tabulated data must be in written form and include all of the following:

• Identification of the parameters that affect the selection of a protective system drawn from such data
• Identification of the limits of use of the data
• Explanatory information as may be necessary to aid the user in making a correct selection of a protective system from the data

At least one copy of the tabulated data, which identifies the registered professional engineer who approved the data, must be maintained at the jobsite during construction of the protective system. After that time, the data may be stored off the jobsite, but a copy of the data must be made available to OSHA on request.

Option 4: Design by a Registered Professional Engineer

A registered professional engineer must approve support systems, shield systems, and other protective systems that do not use option 1, 2, or 3. Designs must be in written form and must include the following:

• A plan indicating the sizes, types, and configurations of the materials to be used in the protective system
• The identity of the registered professional engineer approving the design

At least one copy of the design must be maintained at the jobsite during construction of the protective system. After that time, the design may be stored off the jobsite, but a copy of the design must be made available to OSHA on request.

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