Excavation Competent Person: Duties, Inspections, and Penalties

An excavation competent person is the individual an employer designates to identify existing and foreseeable hazards at a trenching or excavation site and who has been given the authority to take immediate corrective action, including stopping work and removing exposed workers. OSHA’s construction standard builds the role around two things at once: technical knowledge of soil, protective systems, and site conditions, and real authority granted by the employer to act on that knowledge without waiting for approval.¹

Knowledge Plus Authority

The second half of the definition is what makes the role real. In practice, authority means the competent person can order workers out of a trench, halt excavation, or require changes to the protective system without calling a supervisor first. The employer must grant this power explicitly. A foreman who understands soil mechanics but has to phone the office before pulling a crew out of a failing trench does not meet the definition.²

The scope can vary by task. Someone qualified to conduct daily inspections may not be qualified to design a structural ramp. OSHA has clarified that one person can fill multiple competent-person roles under Subpart P, but only if they genuinely possess the knowledge and authority for each specific activity.²

Classifying the Soil

Almost every decision on site flows from soil classification. Soil type determines how steeply the walls can be cut, what shoring or shielding is required, and whether entry is safe at all. Get this wrong and everything after it is wrong.

OSHA recognizes four categories, ranked from most to least stable:

Stable rock: natural solid mineral matter that can be excavated with vertical sides and remain intact.
Type A: cohesive soils with unconfined compressive strength of 1.5 tons per square foot or greater, such as clay and sandy clay. Soil loses Type A classification if it is cracked, subject to vibration, previously disturbed, or has water seeping through it.
Type B: cohesive soils between 0.5 and 1.5 tons per square foot, including silt, angular gravel, and any soil that would otherwise qualify as Type A but is cracked or vibration-affected.
Type C: 0.5 tons per square foot or less. Gravel, sand, loamy sand, submerged soil, and any soil with freely seeping water all fall here.³

Classification requires both visual and manual analysis. Visual indicators include cracks or fissures in the exposed face, water seepage, layered systems dipping toward the trench, and previously disturbed ground. Standing water running out of a trench wall almost always signals Type C regardless of how the soil looked when dry.

Manual tests give objective data. A pocket penetrometer pressed into a freshly cut face reads unconfined compressive strength directly. The plasticity test (rolling soil into a thin thread and seeing whether it holds when dangled) confirms whether the soil is cohesive. Finger pressure on a sample reveals fissures by showing whether it breaks along distinct planes. Each test must use soil from the excavation itself, not surface material.

Choosing the Protective System

Once the soil is classified, the competent person selects a protective system. The regulation sets a clear threshold: any excavation five feet or deeper requires cave-in protection unless it is cut entirely into stable rock. Below five feet, protection is still required if the competent person sees any sign of possible cave-in.⁴ That judgment call on a marginal four-foot trench is exactly the kind of decision the role exists to make.

The three main options are sloping (cutting walls back at a safe angle), shoring (support structures like hydraulic jacks against the walls), and shielding (a trench box inside the excavation). The simplest approach, which needs no engineering, is to slope every wall at the maximum angle for Type C: 1½ horizontal to 1 vertical, roughly 34 degrees from horizontal. That is conservative for any soil, but it means moving a lot more dirt.⁵

When soil is properly classified and Appendix B applied, steeper slopes open up:

Stable rock: vertical (90 degrees).
Type A: 3/4 horizontal to 1 vertical (53 degrees). For short-term work in trenches 12 feet or shallower, 1/2 to 1 (63 degrees) is allowed.
Type B: 1 to 1 (45 degrees).
Type C: 1½ to 1 (34 degrees).⁵

Any excavation deeper than 20 feet requires a protective system designed by a registered professional engineer, regardless of soil type. The competent person still runs the daily inspections and can override the engineered design if site conditions change, but the initial design sits outside the role.

Daily Inspections

Inspections are the most visible duty. The regulation requires inspection of the excavation, adjacent areas, and protective systems before work begins each day and as needed throughout the shift, with additional inspections after every rainstorm or any other event that increases cave-in risk.⁶ “As needed throughout the shift” deliberately puts the burden on judgment rather than a fixed schedule. A stable trench in dry weather might need one midday check. A deep cut in Type C soil next to a busy road might need near-continuous monitoring.

When an inspection reveals evidence of a potential cave-in, protective system failure, or hazardous atmosphere, the competent person must remove all exposed workers immediately, and work cannot resume until the hazard is corrected.⁶ This is where authority matters most. Hesitating because a general contractor is pressing the schedule is exactly the failure mode the standard is trying to prevent.

What Gets Checked

Each inspection covers a consistent set of items. Excavated material, equipment, and other loose objects must sit at least two feet from the trench edge, or retaining devices must prevent anything from rolling in.⁶ Spoil piles creep toward the edge over the course of a shift as new material lands on them, and it is one of the most common violations on trenching sites.

Access and egress are checked every time. Any trench four feet or deeper needs a ladder, stairway, ramp, or other safe exit positioned so no worker travels more than 25 feet horizontally to reach it.⁶ As the trench lengthens during the day, new exit points have to be added. A ladder compliant at 8 a.m. may leave workers 40 feet from an exit by noon.

Water conditions get close attention. Standing water, seepage from the walls, and rain runoff all degrade soil strength, sometimes fast enough to reclassify a Type B soil as Type C within hours. The competent person monitors any water removal equipment and confirms surface water is diverted away from the excavation.⁷

Underground Utilities and Atmospheric Testing

Before the first bucket of dirt moves, the competent person confirms that underground utilities have been located. The regulation requires the employer to determine the estimated location of sewer, telephone, fuel, electric, and water lines, and any other buried installations, before opening an excavation. Utility companies must be contacted and asked to mark their lines. If a utility company cannot respond within 24 hours, work may proceed only with detection equipment and extreme caution.⁶ As digging approaches an estimated location, the exact position must be pinpointed by safe methods, typically hand digging or vacuum excavation rather than a backhoe.

Excavations near landfills, fuel storage, or chemical facilities can develop oxygen-deficient or toxic atmospheres. OSHA requires atmospheric testing before anyone enters an excavation deeper than four feet wherever oxygen deficiency or hazardous gas could reasonably be expected. The oxygen threshold is 19.5 percent, and flammable gas concentrations above 20 percent of the lower explosive limit require ventilation or evacuation.⁶

When a hazardous atmosphere exists or could develop, emergency rescue equipment (breathing apparatus, safety harnesses and lifelines, and basket stretchers) must be readily available at the excavation. Workers entering deep, confined excavations such as bell-bottom pier holes must wear a harness with a lifeline that is individually attended at all times.⁸

Does the Competent Person Have to Stay on Site All Day?

OSHA has stated there is no blanket requirement for the competent person to be physically present at the site at all times. The person can leave periodically, so long as the inspections needed to identify hazardous conditions actually get done.⁹

Whether the person needs to stay depends on site conditions. A shallow trench in stable soil with no water issues and no nearby traffic might be fine with periodic visits. A 15-foot cut in Type C soil next to a busy highway with a water table two feet below grade is not. The regulation puts that call on the competent person’s judgment, and OSHA will evaluate it after the fact if something goes wrong.

Documentation

Subpart P does not include a specific recordkeeping mandate. No regulation requires a particular form. OSHA’s own inspection checklist, however, lays out what a defensible daily log should capture: project identification, weather, soil type, protective system in use, trench dimensions (depth, width, length), and confirmation that each safety requirement was verified. The competent person signs and dates the log.⁷

The checklist also documents whether utility companies were contacted, whether atmospheric testing was performed and its results, and whether emergency rescue equipment is available. In an enforcement action, this documentation is often the difference between a defensible position and a willful violation charge. Proving to an OSHA compliance officer that a proper inspection happened is very hard when nothing was written down.

How Someone Becomes a Competent Person

There is no government-issued competent person license or certificate. OSHA has been explicit: completing a training course does not automatically make someone a competent person. The definition is built around capability, not credentials. A course might not cover everything a particular site needs, and even a thorough course cannot verify that someone applies the material correctly under pressure.¹⁰

No training program can grant authority either. Only the employer can do that. The employer bears responsibility for selecting someone with genuine knowledge of soil mechanics, protective systems, and the excavation standards, and then formally authorizing that person to stop work and remove employees without needing management approval.¹¹ Training in the $50 to $300 range provides a useful foundation, but the employer’s designation, backed by real authority and verified through demonstrated ability on site, is what creates a competent person under the law.

Because conditions differ dramatically between sites, the designation is effectively site-specific. Someone competent to inspect a six-foot utility trench in clay may not be competent to oversee a 19-foot sewer excavation in saturated sand. The employer needs to evaluate whether the person’s knowledge matches the actual hazards present, not just whether they hold a completion certificate.

Penalties When the Role Is Missing

OSHA does not treat the absence of a competent person as a paperwork issue. When a trench lacks a designated competent person, or the designated person lacks real knowledge or authority, OSHA typically issues a serious violation, which carries a maximum penalty of $16,550 per violation as of 2025.¹²

If the employer knew about the requirement and ignored it, or showed plain indifference to worker safety, the citation escalates to willful, with a maximum penalty of $165,514 per violation. Repeat violations within five years draw the same maximum.¹² On a site with multiple trenches and multiple unprotected workers, violations stack quickly across a single inspection.

1
Occupational Safety and Health Administration. 29 CFR 1926.650 – Scope, Application, and Definitions Applicable to This Subpart
2
Occupational Safety and Health Administration. Standard Interpretations: Excavation Competent Person Authority
3
Occupational Safety and Health Administration. Soil Classification Training Outline
4
eCFR. 29 CFR 1926.652 – Requirements for Protective Systems
5
Occupational Safety and Health Administration. 1926 Subpart P Appendix B – Sloping and Benching
6
eCFR. 29 CFR 1926.651 – Specific Excavation Requirements
7
Occupational Safety and Health Administration. Guide for Daily Inspection of Trenches and Excavations
8
Occupational Safety and Health Administration. 29 CFR 1926.651 – Specific Excavation Requirements
9
Occupational Safety and Health Administration. Competent Person Responsibilities at Excavations
10
Occupational Safety and Health Administration. Requirements for Being Designated a Competent Person Under Part 1926 Subpart L (Scaffolds)
11
Occupational Safety and Health Administration. 29 CFR 1926.32 – Definitions
12
Occupational Safety and Health Administration. OSHA Penalties