Trenches and Excavations
Trench fatalities are a serious problem in construction. Bureau of Labor Statistics data show that about 25 workers are killed each year in trench-related mishaps. Cave-ins cause about three out of every four fatalities; the remainder are commonly due to struck-bys or electrocutions.
In 2003, the nation experienced a spike in trench fatalities (53, according to preliminary data, later reduced to 48), inviting a detailed OSHA investigation which highlighted important facts about trench dangers. Following its investigation, OSHA undertook a national emphasis campaign, distributing more information about trench hazards and stepping up enforcement. As a result, annual trench fatalities declined.
The results of OSHA’s 2003 investigation are still useful in understanding why trench fatalities occur and how they can be avoided. The main reason trenches collapse is that they are not properly protected. Protective systems were properly employed in only 24 percent of the trenches. In the remainder, a protective system was either improperly used (24%), available but not in use (12%) or simply unavailable (64%).
Further, despite the fact that environmental conditions were a contributing factor in 68 percent of the fatalities, the competent person was not onsite when the fatality occurred 86 percent of the time. Most of the time (65%) the employer had not identified the soil type even though soil type is a factor in trench cave-ins.
Also, a disproportionate number of fatalities (36%) occurred on Mondays, probably because rain or other factors changed conditions over the weekend. Under OSHA regulations, the competent person must inspect trench work in progress before each shift and after any changes in conditions.
The OSHA investigations showed that schedule time was more important than safety in 88 percent of the incidents. Seventy-two percent of the fatalities occurred in trenches less than nine feet deep. Only nine percent occurred deeper than 15 feet.
The most commonly killed employees were construction laborers (53%), with plumbers and pipe fitters following next at nine percent. Most (58%) were killed while installing pipe.
Fifty-six percent of these fatalities were Hispanics, and 52 percent were foreign-born. For 44 percent, Spanish was their primary language. At least 30 percent had been working for their employer for less than a year, and most (59%) worked for a subcontractor.
Only six percent were union members. Since, nationwide, about 20 percent of construction work is union, the expected rate of union fatalities would be near 20 percent. The lower rate suggests that union jobs are safer, that supervisors and workers on union sites are better trained and that the union offers the kind of protection that workers need to speak up about safety issues on the worksite.
Just over half the employers had a written safety and health program, but, of these, only 40 percent covered trenching. Sixty-five percent provided no trench safety training. Most employers (71%) had never been inspected by OSHA, but 21 percent had been previously cited by OSHA for trench safety violations.
About three in every four fatalities occurred at residential worksites. Most companies were small; 42 percent had fewer than ten employees. Though, typically, five or less workers were present on the site when the incident occurred, most of the projects (52%) involved contracts worth $100,000 or more.
Although trench and excavation work can be very dangerous, injuries and fatalities are completely preventable. For LIUNA signatory contractors that participate in the LHSFNA, the OSH Division can provide assistance in the development and implementation of trench safety programs. For help, call the OSH Division.
TrenchesIs That a Permit-Required or Non-Permit Required Confined Space?
Fatality Data Sheds Light on Occupational Safety and Health Trends
Not All Excavation and Trench Deaths Are from Cave-ins
OSHA Steps Up Oversight of Trenches and Excavations
Health & Safety Headlines
New Video Shows 5 Trench Safety Tips You Need to Know
LHSFNA Toolbox Talks Promote Safety, Health on the Job
Emergency Action Plans Help Keep Workers Safe
Watch How Quick a Trench Can Collapse
A Pipeline Primer for Construction Laborers
What to Watch for as Pipeline Work Grows
- Preventing Worker Deaths from Trench Cave-Ins (also in Spanish)
- Trench Safety Awareness- Interactive NIOSH eTool
- NIOSH Publication
- OSHA Standard
- OSHA Topic Page
- OSHA Publication (2226)
- OSHA Construction eTool
- OSHA Fact Sheet
- Excavations in Construction (OSHA video in English and Spanish)
- Oregon OSHA
- Trenching in a Dangerous and Dirty Business
- Excavation and Trenching Safety Program - Project Manager's Manual
- CPWR- Strategies to Prevent Trenching-Related Injuries and Deaths
- Trenches and Excavations Checklist
- Auburn University Tutorial
- Ohio State University Fact Sheet
- Virginia Tech University
- Excavation Assessment Form
- Oklahoma State University Trenching and Shoring Procedures
- WorkSafeBC — A Guide to Safe Work Practices (6-Part Series 20:47):
- NAHBTV-Trenching and Excavation Safety (4:12)
- I Safety Solutions (3:45)
- Installation and Removal of a Vertical Shore (3:19)
- Trench Shield Inspection (4:04)
- Trench Rescue (1:02)
- OSHA Standard-OTI (22:58)
TrenchesIs That a Permit-Required or Non-Permit Required Confined Space? (June, 2019)
Fatality Data Sheds Light on Occupational Safety and Health Trends (March, 2019)
Not All Excavation and Trench Deaths Are from Cave-ins (March, 2019)
OSHA Steps Up Oversight of Trenches and Excavations (January, 2019)
Health & Safety Headlines (December, 2018)
New Video Shows 5 Trench Safety Tips You Need to Know (October, 2018)
LHSFNA Toolbox Talks Promote Safety, Health on the Job (July, 2018)
Watch How Quick a Trench Can Collapse (December, 2016)
A Pipeline Primer for Construction Laborers (August, 2015)
What to Watch for as Pipeline Work Grows (November, 2014)
Emergency Action Plans Help Keep Workers Safe (April, 2014)
Torch Toxic Hazards (December, 2008)
Data Suggest Progress in Trench Safety (April, 2008)
PEST Program Supports OSHA Enforcement (Summer, 2007)
811 Number to Limit Underground Utility Strikes (March, 2007)
New Trench Safety Training Videos Available (November, 2006)
PEST Program Boosts OSHA Construction Enforcement (Winter, 2006)
Use a Box or Slope that Trench? (September, 2005)
Spike in Trench Fatalities Spurs Action (Fall, 2004)
Union Trenches Safer than Non-Union (Winter, 2003)