“Over the Counter” or “Prescription” Engineering for Excavation Safety.

Recently when explaining some of the protective system options in Subpart P, it occurred to me that most people understand over the counter and prescription medications. Why not apply that concept to protective systems when looking at the options found in 1926.652 (c)(2) Manufacturer’s Tabulated Data, (c)(3) Other Tabulated Data, and (c)(4) Design by a Registered Professional Engineer.

We can go to a drug store and purchase some medications over the counter. We are instructed to use those medications per the label. However, other medications have more controls and cannot be obtained without a prescription. I’ll try to apply this analogy to some of the protective system options.

Option 1926.652 (c)(2) covers designs using manufacturer’s tabulated data. This would be like over-the-counter medications. As long as we follow the manufacturer’s specifications, recommendations, and limitations with these shoring and shield products we are following OSHA. The manufacturer’s tabulated data is stamped by an engineer.

Option 1926.652 (c)(3) covers designs using other tabulated data. This would also be like over-the-counter medications. It could be any number of protective systems (e.g., sloping or shoring) but this tabulated data is stamped by an engineer, and we are good as long as we work within the parameters of the tabulated data.

Note: The difference between manufacturers’ tabulated data and “Other” tabulated data can be a bit confusing so I’ll over-simplify just to keep this short and sweet. My apologies in advance to you trench safety nerds out there, as I brutally generalize.

Manufacturer’s tabulated data – There are several companies that are manufacturing shoring and shield equipment. They provide “operating instructions and working parameters” that allow the end user to use these systems creatively as long as they remain within the specifications, recommendations, and limitations – which are known as manufacturer’s tabulated data.

Other tabulated data – These instructions and working parameters can, but do not necessarily include equipment. There could be tabulated data for any other protective system such as sloping or benching. For example, a pipeline company may wish to get “customized” sloping and benching methods from an engineer for a project. They might choose this option over Appendix B (Sloping and Benching) in Subpart P which is a “one size fits all” answer, and that may not be ideal for the pipeline company’s needs. Both options would be legal and safe, as long as used per recommendations, specifications, and limitations.

Let’s move on to the “prescription strength option.”

Option 1926.652 (c)(4) is called “Design by a registered professional engineer” and is different from the previous options. This would be like a prescription medication in that the engineer determines every detail of this protective system, including soil classification and layout. This design is not to be duplicated on other jobsites, similar or not, without the stamped approval of the engineer.

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