Do It Your Way and Safe at the Same Time

I recently received a question regarding sloping at the open end of a trench shield that was being used on a pipeline project.  The manufacturer’s tabulated data was unclear on the issue and an inspector was requiring that the sloping adhere to the OSHA Appendix B for sloping and benching. This is a prime example … Read more

Engineers Corner: A Closer Look at Site Specific Shoring Plans

Site-specific shoring plans originated in response to OSHA Subpart P-1926.652(c) (4) Option 4, Design by an Engineer. In the standard, OSHA states: 1926.652(c)(4)(i)- Support systems, shield systems, and other protective systems not utilizing Option 1, Option 2, or Option 3, above, shall be approved by a registered professional engineer. 1926.652(c)(4)(ii)-Designs shall be in written form … Read more

Engineer’s Corner: Trench Shield Inspection and Repair

It is well understood that the use of shoring equipment requires regular inspection and maintenance. Understanding how to inspect a shoring device, what needs to be focused on, and how to make practical decisions about what is observed, is not so clear.  Steel shoring shields have very long lifetimes, which depend on how the product … Read more

Engineer’s Corner: Excavation Shoring Equipment Job Hazard Analysis

On June 19th through 24th, the National Utility Contractors Association (NUCA) will be sponsoring a Trench Safety  Stand-Down to raise awareness and prevent accidents in excavation work.  One of the major ideas behind a safety stand-down is to increase awareness and focus on safety by encouraging participants to stop, think about safety, and determine ways … Read more

Engineer’s Corner: National Trench Safety’s Load Measuring Telemetric Pin

National Trench Safety recently previewed its newly developed telemetric pin at the CONEXPO/CON-AGG construction equipment show in Las Vegas, Nevada. The telemetric pin was installed within the leg of a hydraulic excavation brace supporting an in-ground slide rail pit. As part of the demonstration, hydraulic loads were applied to the pin which was wirelessly transmitted … Read more

Engineer’s Corner: History and Reflections on the OSHA 2-Ft “Off the Bottom” Rule

There are many requirements within OSHA Subpart P that may not be entirely clear. One requirement that I continually get questions on is what we call the” 2-ft rule”.   The 2-ft rule provides that a protective system, such as shoring shields and hydraulic shores, cannot be held more than 2-ft off the bottom of an … Read more

Engineer’s Corner: Innovation in the Shoring Industry

It starts with what’s perceived as a great idea to accomplish things better, faster and or safer. It always seems like a no brainer to adopt great ideas and improve how things are done in hindsight. Inventors and entrepreneurs invest huge sums of time and money into developing and refining these ideas.  Once t he … Read more

Engineer’s Corner: Reading Soils Reports and Bore Logs from a Contractor’s Perspective

On practically every construction project involving soil, whether excavating, moving or building atop, there is usually a geotechnical investigation. The report is financed and commissioned by the owner and project design engineer for the purpose of obtaining soil properties relative to structural stability and longevity of the project.  The basic exploratory program most often consists … Read more

Engineer’s Corner: The Shoring System Selection Process

Excavation support and shoring decisions can be complicated. The amount of soil conditions and variables that go into defining the problem and the shoring system alternatives to choose from can be overwhelming.  The results of getting it wrong can be very expensive, while being overly cautious can result in not getting awarded the job or … Read more

Engineer’s Corner: Temporary Bridges Used for Worker Access in Excavation Work

Excavation work presents several situations where temporary access bridges can be necessary. One common example is a pipeline excavation utilizing shoring shields combined with sloping, which will require a bridge to provide worker access from the un-sloped surface to the shoring shield.  OSHA Subpart P, 1926.651(l) provides some guidance in this respect:  “Walkways shall be provided where employees or equipment … Read more

Engineer’s Corner: Fundamentals of Construction Cost Estimating

At National Trench Safety we are in the process of developing useful shoring cost estimating information for construction managers and estimators. In the process, I am developing a series of articles about the estimating process. Construction cost estimating can easily be broken down in a systematic way. Everything that goes into building anything can be … Read more

Engineers’ Corner: Water, Dewatering, Considerations and the Impact Upon Shoring System Selection and Design

Water has an undeniable impact on the selection of shoring systems. The presence of water can have a significant impact on soils, which is why water is commonly mentioned in most manufacturers ‘ tabulated data.  The water table tells the contractor where to expect water, it’s based upon soil sampling on a specific job site, … Read more

Engineer’s Corner: Providing Clarity for OSHA Requirements for Protective Systems 20 Feet or Deeper

One of the more interesting questions I receive from contractors well versed in both the excavation standard and manufacturer’s tabulated data, regards the application of OSHA’s 20-ft depth requirement for site-specific engineering. Quite often I hear the statement “anything over 20-ft deep must be designed by a registered engineer.”  There is a lot of confusion … Read more

Engineer’s Corner: Contractor, Project Manager Convicted in Wrongful Death: What It Means for the Underground Industry

I recently served as an expert witness in a wrongful death (involuntary manslaughter) case in California related to a trench collapse.  In this particular case, the court had held the prime contractor and project manager personally responsible for not following state laws regarding worker protection in excavations and sentenced each to two years in prison.  … Read more

Do It Your Way and Safe at the Same Time

I recently received a question regarding sloping at the open end of a trench shield that was being used on a pipeline project.  The manufacturer’s tabulated data was unclear on the issue and an inspector was requiring that the sloping adhere to the OSHA Appendix B for sloping and benching. This is a prime example … Read more

Manufacturer’s Tabulated Data: Understanding the User’s Responsibility

This article is the second of a three part series regarding manufacturer’s tabulated data. When reviewing the obligations of tabulated data there are certain requirements of the user of the tabulated data. Those requirements include the following: Employer’s Competent Person must determine the load that will be placed upon the shoring system, which include the … Read more

Manufacturer’s Tabulated Data: What to Look for and Expect

This article will be the first of a three part series regarding manufacturer’s tabulated data. According to the OSHA Subpart P Excavations standard, “tabulated data” means tables and charts approved by a registered professional engineer and used to design and construct a protective system. The purpose of this tabulated data for shoring equipment is then … Read more

Induced Hazards

It is not known who coined the term “induced hazards”, but OSHA uses the term and defines it as hazards that “arise and are induced from a multitude of incorrect decisions and actions that occur during the construction process.”  Part of the reason for the development of these hazards, is the production mentality of many … Read more

Registered Professional Engineer, Tabulated Data, and Interstate Commerce

Federal and State interstate commerce regulations along with the Federal OSHA regulations state that for manufactured shoring and shielding equipment, the structural certification stamp from the state where the shoring is manufactured is to be accepted in all states. The following definition applies to this: 1926.650(b)-Definitions applicable to this subpart. “Registered Professional Engineer” means a … Read more

Surcharge Load Decisions for the Competent Person

One of the most complicated and least understood requirements of the OSHA Subpart P-Excavations Standard is surcharge loading. There is very little information provided about how to determine and deal with surcharge loads, while there is a lot about requiring the competent person to consider surcharge loads in shoring selection decisions.  Here is the requirement … Read more

Exceptions to the OSHA Requirements for Protective Systems

The following articles are a series focusing on Federal OSHA Subpart P Excavations 1926.652 Requirements for protective systems.     Exceptions to the Rule Although   OSHA allows trenches under 5’ deep to be left unsloped or unshored  it is not a get out of jail free card, there are still requirements that impact the  employer and its … Read more


The Occupational Safety and Health Administration (OSHA) establishes basic standards for employee protection when working in and around excavations.  These standards are very important for keeping employees safe, as well as establishing employer responsibilities.  The OSHA standard addresses excavations in 1926.652(a)(1) specifically stating that employees must be protected from cave-ins while working in excavations.  A … Read more