Page 72 - Occupational Health & Safety, July 2017

CONSTRUCTION SAFETY
Fatality Investigation: 22-Year-Old
Construction Laborer Killed in Trench Collapse
The Kentucky Fatality Assessment and Control Evaluation (FACE) program investigates fatalities and makes recommendations for preventing future similar injuries.
ceived previous safety training with the company. The crew superintendent assigned the victim to assist the excavator operator in taking trench grade measure- ments. No thorough inspection was conducted prior to beginning work, and no soil testing was carried out of the area where the trench work was to take place. Additionally, a trench box and/or shoring supports were not on site.
BY DE ANNA MCINTOSH
A
Area of Collapse
BC
Figure 1. 1) Aerial view of incident scene, B) photo of trench Dcollapse location four months prior to incident, C) section of
trench that collapsed on victim; concrete wall.
Road
13.4’ deep Trench
Concrete all
Trench Collapse
Concrete Wall
13.4’ deep Trench
Trench Collapse
~4-5 ft.
Not drawn to scale
68 Occupational Health & Safety | JULY 2017
www.ohsonline.com
espite the variety of trench safety practices and protective devices available on the market, excavation and trenching remain among the most hazardous operations on
a construction site. As defined by OSHA, a trench is an underground excavation that is deeper than it is wide. Variability in soil types and other environmen- tal factors make working in these crevices a unique safety challenge, and many workers underestimate the sheer weight of only a small amount of collapsed dirt. Shortcuts should never be taken for sake of project expediency.
A recent fatality investigation by Kentucky FACE, a NIOSH-supported occupational fatality research program, details the preventable death of a young fa- ther in a trench collapse.
A local highway construction company (in busi- ness since 1992) had been hired as a subcontractor to install an 18-inch-diameter storm sewer drainage pipe alongside a two-lane road. On the morning of the incident, the superintendent of the crew of 10 held a pre-work meeting to discuss the work to be done that day. The meeting included general safety awareness but did not specifically address proper trench safety and trench collapse hazards. All employees had re-
The excavator operator stated he was benching the street side of the trench, similar to a previous job they had performed in the past. Photos of the scene suggest partial benching of the top of the trench (see figure 1C), but the trench was too close to an adja- cent concrete wall (depicted in figure 1) to be properly benched. The excavator operator also stated that the superintendent witnessed the victim enter and exit the unprotected trench multiple times that morning.
At approximately 9:30 a.m., the construction work- er jumped into the trench to take grade measurements. The excavator operator observed the collapsing of the concrete wall facing side of the trench and yelled to the construction worker to jump out. The construction worker did not have adequate time to escape, and the trench collapsed and buried him under dirt and gravel. Nearby employees jumped into the collapsing trench and tried to rescue the victim by digging. Emergency Medical Services were called and arrived at 9:47 a.m. A trench collapse special response unit from the fire department arrived and recovered the construction worker at 10:52 a.m., unresponsive. Unfortunately, res- cue efforts took too long, and the coroner pronounced the victim dead at the scene at 10:52 a.m.
Lack of Trench Protective System
Performance of a soil test and an adequate trench protective system could have prevented this incident. OSHA requires that all workers in trenches 5 feet or more in depth be protected by sloping, shoring, or the
Figure 2. Diagram of incident scene.
FACE PROGRAM, KENTUCKY INJURY PREVENTION AND RESEARCH CENTER
NEWS CHANNEL WLEX18
OCCUPATIONAL SAFETY & HEALTH PROGRAM, KENTUCKY LABOR CABINET
~45-50 ft.
GOOGLE MAPS