In a grim reminder about the dangers of trench and excavation work, this article from Safety+Health Magazine also serves as a warning to employers. “The court’s decision sends a message to business owners that they can be held criminally accountable and face felony charges if they knowingly fail to protect their workers.”

The owner of Alki Construction LLC has been charged with second-degree manslaughter after an employee was buried while replacing a residential sewer pipe in a trench that had inadequate shoring and was missing a ladder.

Remember to ensure that you have a properly trained Trench Competent Person on site, and check out OSHA's Trenching and Excavation Safety Fact Sheet as a reminder when scheduling trench work.

“We were at a standstill, and if we couldn’t come up with a solution to shore up that part of the structure,” Tim Robson recalls, “we’d be sending our people into a much riskier situation. In fact, some areas were so dangerous, we had to start thinking about things like, “Who’s not married?” and “Who doesn’t have kids?” It was awful, but it was something we had to think about.”     

On September 12, 2001, Tim Robson was sent to the Pentagon with his FEMA Urban Search and Rescue New Mexico Task Force 1 team. Their objectives were to search for survivors, recover victims, structurally stabilize the damaged area of the building, and locate several safes containing classified documents. Because the site was a crime scene, they also had to document and preserve key pieces of information for the FBI.  

Tim’s team began their work in the rubble on the edges of the impact zone, but they quickly reached the area where the building hadn’t completely collapsed. It was inside the building where there was the highest probability of finding survivors, but it was also too dangerous to send rescuers into these overhead environments before stabilizing the structure. The building had already suffered pancake and lean-to collapses in the hours after initial impact. Extreme heat from the explosion and burning jet fuel weakened the building’s support columns. This created an extraordinarily hazardous environment for the search and rescue teams.  

“The left side of the impact zone, on the outermost ring of the Pentagon – part of that wall was actually moving,” Tim recalls. “The loads were so great… any movement was very hazardous. It was definitely stressful. But we were extremely task-oriented and we wanted to get the job done and get out of there.” 

The textbook approach to stabilizing a heavy building with extensive structural damage like this was to stack 6x6 timbers in a box around each damaged column. “It’s just like stacking Lincoln Logs,” explains Tim. This provides a very strong and stable support structure in case the column fails.  

However, it only works if there’s something substantial overhead for the stacked timbers to support, and in the case of several weakened columns on the outer edge of the building, the ceiling didn’t exist all the way around the columns.  

The team put their heads together to come up with alternative solutions and workarounds, but nobody was very comfortable with any of the ideas floated. Tim knew that the stacked timbers approach derived its strength from the joints at the corners where the timbers overlapped. With that principle in mind, Tim came up with the idea to connect two boxes of stacked timbers together by using longer timbers on one edge of each box and overlapping those longer timbers.  

By Skip Williams

Contributors: Deputy Chief Kenneth Jenkins, Captain Tom Horn and Captain Anthony Morley, Charleston Fire Department, Rescue 115, and Russ Fennema, Jay Dee Contractors

Note: The following article recounts a very successful rescue that took advantage of available resources at the scene. Roco Rescue wants to share stories like this one to remind our readers that lessons learned can be gleaned from successful rescues just as they can from rescues that didn’t go so well. The important point is to take the time to perform a debriefing as soon as possible after the rescue effort. This is the time to capture the thoughts and comments from the team members while it is still fresh in their memories. Any important lessons learned need to be captured through documentation and then SHARED. The learnings can become part of your SOP/SOI or they can become integrated into your formal training. 

The other point that this article makes is to know and understand your equipment. We regularly train with our ropes and hardware, and we all tend to learn the operating limits and capabilities of said equipment. However, we need to be just as familiar with our peripheral equipment such as atmospheric monitors, radios, and etcetera. Consider spending some of your team training time learning more about that equipment and how to properly use it and what its idiosyncrasies may be. All the equipment we use should be considered life support equipment, and the word “life” should grab your attention and motivate you to know all you can about it. 

In March 2019, Rescue 115 of the Charleston Fire Department was dispatched at 09:02 hours to “man down” at an address on Shepard Street some 5 1/2 blocks NW of station 15 on Coming Street. En route, Captain Tom Horn realized the address was familiar as the entrance to the Coming Street retrieval shaft of the Charleston tunnel project (Figure 1). Now they were 2 blocks from the scene and he immediately called for Ladder 4 also from station 15, and nearby Engine 6 and Battalion 3 from nearby station 6. R115 arrived at 09:06 hours.

The Coming Street retrieval shaft is a vertical shaft 168 feet down and 20 feet in diameter to a 15-foot diameter tunnel being bored for flood control (Figure 2). Just as R115 arrived at the scene, the 12-man cage had been weight tested and prepared for lowering by crane. As R115’s four-man crew was about to be lowered into the shaft, Captain Horn eyed Captain of Ladder 4 and transferred command to him.

Just as R115’s crew got to the bottom, the patient arrived at their location from three quarters of a mile in the tunnel on a horizontal flat car driven by a battery-powered locomotive (Figure 3).

Captain Horn called for the lowering of the backboard and Stokes basket. The topside crew decided to use the crane again rather than lower with ropes. The county EMS was not included as joint training is not done. Back down at the tunnel, the patient was secured, placed in the  12-man cage, along with R115 members and 2 construction workers. The patient at the top of the shaft was treated by county EMS and was off to the hospital at 09:40 just 38 minutes from the initial call.

There are always lessons learned at any rescue. From prior experience, a member was assigned to the crane operator to ensure that the crane was moved under Fire Department control. The Fire Department used the construction company’s gas detectors because they knew that the detectors were calibrated daily. In retrospect, the Fire Department would use its own gas detectors. Also, the backboard and Stokes basket should have gone down on the first lowering to the tunnel.

The usage of gas monitors had been delayed because of differences in calibration between the fire department monitor and a plant monitor. There is no one gas that is best for calibration of fire department gas detectors because many different exposures are encountered. For a particular industrial site, the explosive gases are most likely known. 

Figure 4 shows that the Lower Explosive Limit (LEL) varies according to which hydrocarbon is present. Figure 5 shows correction factors if the monitor is calibrated with one gas and exposed to another. The Fire Department meter was calibrated with methane so that 0.5% by volume of methane reads 10% of LEL. A meter calibrated with pentane has a correction factor of 2 for methane. So, if a meter calibrated with pentane reads 10% LEL in pentane, the meter would read 5% LEL in methane. lf anything, the gas in the tunnel would be methane, but in actuality, the meters read zero no matter what calibration gas was used. 

The reason pentane is sometimes used for calibration is that it overestimates the actual LEL. The caveat is that if the meter is poisoned for methane, a methane bump test is indicated. A sensor can be poisoned by chemicals like silicone.  Note well, silicone is a component of Armor All which should not be exposed to a LEL meter on a fire truck. The lesson learned here is to understand the effect of different gases on a sensor and a Fire Department may encounter many different gases.

Author Bio:

Skip Williams was a volunteer firefighter for 20 years. His last position was captain of the high-angle rescue team and emergency medical technician. He has a Bachelor of Electrical Engineering from Georgia Tech and M.S. and Ph.D. from Rutgers University and has held teaching positions at Rutgers University and the Medical College of Georgia. He designed and patented an artificial heart assist device. He is a Registered Professional Engineer in New Jersey and is a practicing engineer with Condition Analyzing Corporation engaged in condition monitoring of ships. 

Note: Captain Tom Horn is a graduate of two Roco Rescue courses.

By Pat Furr, Safety Officer & VPP Coordinator

The US Coast Guard issued a warning on the dangers of confined spaces after three crew members died of asphyxiation on a drilling rig. Although this tragedy occurred during a maritime operation and does not fall under the OSHA general industry nor the construction industry standards for permit required confined spaces, OSHA’s 1915 Subpart B does have clear guidance regarding confined and enclosed spaces and other dangerous atmospheres in shipyard employment. Additionally, 1915 Subpart B Appendix B provides the US Coast Guard requirements for an authorized person in lieu of a marine chemist. The USCG Safety Alert does not mention any member of the crew being either a marine chemist or a USCG authorized person assigned to evaluate the atmospheric conditions of the space. 

This tragedy follows an all-too-common pattern of multi-fatality incidents where subsequent workers died in an attempt to rescue the original victim. While it is clear that there were considerations and provisions to ventilate the toxic gases that were either present in the space or were introduced into the space, it is obvious that the passive ventilation attempts fell well short of what was required. OSHA, ANSI, and the USCG all provide easily accessible and clear guidance regarding working in confined spaces.

Please take it upon yourself to ask anyone and everyone that you encounter that may be entering confined spaces: "Does your employer have a permit required confined space program that is at least compliant with OSHA?" It just may save their life. 

For a deeper understanding of OSHA’s requirements for permit required confined space rescue, including the factors that should be considered for determining whether non-entry is feasible, check out our article, “Confined Space Rescue: Non-Entry or Entry Rescue?” To learn how teams can share responsibility for risk-assessment and mitigation, check out "Safe Confined Space Entry - A Team Approach."

Click here to read the news article about this incident and the USCG Safety Alert.

Pat Furr is a chief instructor, technical consultant, VPP Coordinator and Corporate Safety Officer for Roco Rescue, Inc. As a chief instructor, he teaches a wide variety of technical rescue classes including Fall Protection, Rope Access, Tower Work/Rescue and Suspended Worker Rescue. In his role as technical consultant, he is involved in research and development, writing articles, and presenting at national conferences. He is also a member of the NFPA 1006 Technical Rescue Personnel Professional Qualifications Standard. Prior to joining Roco in 2000, he served 20 years in the US Air Force as a Pararescueman (PJ).

A rash of trench incidents has left behind multiple fatalities and untold devastation to families. The following incidents occurred in only a matter of weeks. We log these incidents as a reminder of how deadly trenches can be. Proper training and the right equipment are needed before attempting a rescue; or, as in most cases, a recovery.

These events came to our attention over recent weeks including one incident in which the victim was not even in the trench until the ground collapsed beneath him. Another incident happened adjacent to the department where one of our Roco Chief Instructors (Brad Warr) works in Idaho. His department also responded.

As you read these accounts, pay careful attention to how tragic and deadly these incidents can be.

We’ve also included two successful trench rescues at the end of these stories.

REMEMBER: OSHA advises to “Protect Yourself…” Do not enter an unprotected trench! Trenches 5-feet deep or greater require a protective system unless the excavation is made entirely in stable rock. Trenches 20-foot deep or greater require protective systems designed by a registered professional engineer. OSHA also requires safe access and egress to all excavations, including ladders, steps, ramps or other safe means in trenches 4-feet or deeper. The devices must be located within 25-feet of all workers.

Worker Killed After Being Trapped in 16-Foot-Deep Trench

(4/26/19) DEKALB COUNTY, GEORGIA 

Fire-Rescue crews were called out to a subdivision construction site Friday afternoon in DeKalb County after crews reported that a 16-foot trench had collapsed on top of a worker.

Firefighters said that the man was helping to guide a backhoe as it dug the trench and the ground gave way, trapping the construction worker inside.

"The ground below him caved in and he fell into the hole. The hole was about 16 feet deep and about two feet of dirt on each side of the hole fell on top of the victim and covered him up," said Capt. Dion Bentley with DeKalb Fire Rescue.

Firefighters reported that two other construction workers at the site tried to rescue the victim when it first happened.

Investigators said there was no trench box inside the hole when the collapse happened. Crews said that was because no one was working inside the trench when the collapse happened. It is unclear if that violates OSHA rules. OSHA officials will now be responsible for investigating the incident.

Man Dies Before Being Rescued from Trench

(4/25/19) ALPINE, UTAH

A man working to install a pool in the backyard of a home died in a trench collapse Wednesday afternoon, authorities said.

The victim, a 53-year-old man, was pronounced dead at the scene from injuries suffered in the collapse, Lone Peak Fire Chief Reed Thompson said.

Lone Peak Fire Department crews responded to the collapse shortly after 1 p.m. When crews arrived, they found a man with dirt up to his waist.

"We were told by others on scene that prior to our arrival, he had been encapsulated up to his neck," Thompson said.

The man died before crews could rescue him from the fallen trench, Thompson added. The Lone Peak Fire Department was helped in the recovery effort by the Utah County Technical Rescue Team, which includes crews from American Fork, Lehi, Pleasant Grove and Orem.

"In this particular incident, the victim was in a trench that did not have any security measure in place — such as shoring — and was deeper than what OSHA requires at 4 feet," Thompson said. "As a result of that, you've got heavy dirt and other materials that can potentially fall or collapse into the open hole, which is what occurred."

Man Dies When Trench Collapses

(4/21/19) LYCOMING COUNTY, PENNSYLVANIA

One man was killed in a rural area when a trench dug to fix a water line problem collapsed around him. The man was pronounced dead in the trench but it took nearly three hours to remove the body. Rescuers first had to shore the sides of the eight-foot deep ditch. The coroner listed asphyxiation as the cause of death.

While there were no witnesses to the collapse, family members believe he was buried about 15 minutes in the 15-foot long x 6-foot wide trench. Family members had cleared the clay-based soil from around the victim’s head before emergency responders arrived at the scene.

Although no pulse was detected, rescuers continued to remove dirt down to his waist in a rescue effort. Those efforts were discontinued once a paramedic with a heart monitor determined he was dead.

Two Workers Die in Colorado Trench Collapse

(4/17/19) WELD COUNTY, COLORADO

Two construction workers died after having been trapped in a 15-foot-deep trench that collapsed on top of them at a Colorado residential property.

The Fire Chief of Windsor Severance Fire Rescue said that the two men were working in the trench when it collapsed, completely burying them in dirt and compact soil.

Despite an hours-long rescue operation, both men died from injuries sustained in the incident. It was early the next morning when the fire department announced that the operation had switched from a rescue to a recovery effort, which was expected to take several more hours.

When Windsor Fire Rescue arrived on the scene, workers had been able to insert a PVC pipe to one of the trapped men, allowing him to communicate with the rescue crews above ground. No contact with the second worker was made, the release said.

The soil condition of where the workers were trapped made the excavation process more difficult as only small hand shovels and buckets could be used since the ground was both unstable and compacted.

Extreme caution was used to prevent further injury to the two men, the release said.

When rescue workers reached the trapped men, they had already succumbed to their injuries.

(Photo used above is courtesy of Windsor Severance Fire Rescue.)

Two Dead After Trench Collapse

(4/10/2019) NEW PLYMOUTH, IDAHO

Two men, working for a private company installing irrigation pipes in a rural area, were killed when the trench they were working in collapsed. Emergency responders were able to extricate the two men from the trench, but were unable to resuscitate them.

Payette County dispatchers sent three different fire departments, paramedics, law enforcement, two separate highway departments and a private construction company to the scene to extricate the men.

TRENCH RESCUES:

Man Rescued after being Buried Up to His Waist

(April 2019) FREMONT, CALIFORNIA

A man was rescued when he was trapped up to the waist in a trench incident. The Fremont Fire Department was able to remove the individual from the trench. The victim was hospitalized with moderate injuries.

Construction Worker Rescued from Trench

(April 2019) CALDWELL, IDAHO

A construction worker was taken by air ambulance to a local hospital after getting hit by a bucket that fell off a tractor into a trench, according to the Caldwell Fire Department.

Either water or sewer lines were being installed when a bucket detached from a tractor and injured a construction worker in the approximately 20-foot-deep trench, said Caldwell Fire Chief Mark Wendelsdorf.

The bucket had to be removed from the trench before the man was rescued, though Wendelsdorf did not know if that meant the man was pinned by the bucket, or if it was only preventing him from getting out.

The Nampa Fire Department’s ladder truck was used and acted as a rigging system to get the injured man out.

The trench did have a trench box and shoring in place. OSHA is investigating the incident, according to a Department of Labor spokesperson.

The rescue took about an hour, as crews made sure that the trench would not collapse while the technical rescue took place.

NOTICE:
At some time, every emergency responder may be called to a trench incident – whether a rural area or industrial construction site. Know, at minimum, how to protect yourself. Roco Trench Rescue courses offer safe, practical techniques for dealing with trench rescue incidents. Sign up now or call to observe one of our hands-on trench classes.