Trenching PDF Version
 

OSHA Office of Construction & Engineering

Yes, there really is a worker in the bottom of the 35-foot trench. No, it wasn’t staged. Yes, the company was cited for lack of cave-in protection.

OSHA’ s National Emphasis Program (NEP) for Trenches requires all compliance officers to be on the lookout for trenching and excavation worksites. OSHA will inspect worksites where trenching hazards have been observed and reported – either by the public or an OSHA compliance officer.

So far this year, the Illinois Area Offices have conducted 133 inspections under the Trench Program, or 15% of the 864 construction inspections conducted. As reported in the last edition, more than half of the lack of cave-in protection citations in Region 5’s Federal OSHA offices (Illinois, Ohio, and Wisconsin) were issued here in Illinois. Lack of cave-in protection is #3 on the Most Frequently Violated Standards List.

If trenching hazards are so great (people die in trenches) and the means to correct the problem is so easy (trench boxes, shoring), why do we still find so many trenches with no cave-in protection?

Unfortunately, we find that sometimes people are willing to take chances. Some of the “excuses” we hear include: the worker was only going to be in the trench for a few seconds; we’ve been doing this for years and never had a problem; the trench box is down the street and it was too much trouble to get it for just a few minutes; and so on.

Let’s face it, there really aren’t any excuses for not providing cave-in protection. In this edition you will find information on trenching standards and what OSHA looks for in a competent person. More information is available on the OSHA web site: www.osha.gov. You can also call the OSHA area office and ask for help – (we don't have caller id).


Temporary spoil must be placed no closer than 2 ft. from the surface edge of the excavation, measured from the nearest base of the spoil to the cut. This distance should be measured from the crown of the spoil deposit. This distance requirement ensures that loose rock or soil from the temporary spoil will not fall on employees in the trench.

Spoil should be placed so that it channels rainwater and other run-off water away from the excavation. Spoil should be placed so that it cannot accidentally run, slide, or fall back into the excavation.

Competent Person

1926.651(k)(1) requires a competent person make daily inspections of excavations, the adjacent areas, and protective systems for evidence of a situation that could result in possible cave-ins, indications of failure of protective systems, hazardous atmospheres, or other hazardous conditions.

We are frequently asked what a “competent person” is. The employer has the responsibility to designate the competent person

When OSHA shows up for an inspection, the compliance officer will ask the employer’s competent person a series of questions to find out if the competent person can detect the hazards on-site and if they have the authority to take corrective action. OSHA frequently finds that the competent person is quite knowledgeable about the hazards, and how to correct them. They usually have many years of experience in the industry. However, they may have no authority to correct problems. If they can’t, they are not a “competent person.”

The designated competent person should have and be able to demonstrate the following:

  • Training, experience, and knowledge of:

    • Soil analysis;
    • Use of protective systems; and
    • Requirements of 29CFR Part 1926 Subpart P

  • Ability to detect:

    • Conditions that could result in cave-ins;
    • Failures in protective systems;
    • Hazardous atmospheres; and
    • Other hazards including those associated with confined spaces.

  • Authority to take prompt corrective measures to eliminate existing and predictable hazards and to stop work when required.

Slope and Shield Configurations for Type A, B and C soils

1926.652 Appendix B contains specifications for sloping and benching when used as methods of protecting employees working in excavations from cave-ins.



This paper appears in the eLCOSH website with the permission of the author and/or copyright holder and may not be reproduced without their consent. eLCOSH is an information clearinghouse. eLCOSH and its sponsors are not responsible for the accuracy of information provided on this web site, nor for its use or misuse.


 eLCOSH | CDC | NIOSH | Site Map | Search | Links | Help | Contact Us | Privacy Policy



Other Job Site Trade Hazard Site Map Search Spanish Items Help Links Contact eLCOSH Non-English Materials Training Materials NIOSH Home CDC Home eLCOSH Home