Tab Data: What It Is and Why You Need It

Tab Data or certification…some just call it engineering. Call it what you want, it creates value in a trench box. Without it, that asset you have sitting in your yard to protect your workers can be worth little better than scrap prices at the salvage yard.

One may ask, “So what IS it about this sheet of paper that makes it so valuable?” Well, let me attempt to answer that. At first glance one of the things that jumps out on a sheet of Tab Data is the circular stamp that says, Professional Engineer, the engineer’s name, and the state where he is registered. This circular stamp is required on all Tabulated Data for 49 of the 50 states, excluding the lovely state of Michigan, which states: “A support system shall be designed by a qualified employee.”

As for what a “qualified employee” is, here is Michigan’s answer: “Qualified Person” means a person who, by possession of a recognized degree or certificate of professional standing, or who, by extensive knowledge, training, and experience, has successfully demonstrated the ability to solve or resolve problems relating to the subject matter and work.” (
Interesting, I know. I can hear you now, “What do they mean by extensive knowledge, training, and experience?” To that, I am sad to say, there really is no answer offered.

So, back to the Tab Data needed for those living in America’s non-mitten states. Aside from the circular stamp you will also see a set of tables and charts that will tell you how deep the equipment can go and still be safely operated in various soil types. These soil types usually consist of the classifications A, B, C-60, and C-80 taken from the federal OSHA Sub Part P.

Some trench boxes are serialized in which case the corresponding serial number will also be located on the Tabulated Data.

Last, but not certainly not least, you’ll find the easy to glance over but still very important, LIMITATIONS OF USE, heading and a corresponding number of bullet points which explain how the trench box should or should not be used.

IF reading this post leaves you wondering, “Do I have the Tab Data needed for my trench box?” Shoot me an email or give me a call at 877-854-3552.

At Allen Trench Safety we will always do our best to get you what you need to keep your fleet running smooth.

From the Trenches,
Chris Allen