Driving around your town, how many times have you seen workers in a trench working totally unprotected?  As an emergency responder, are you aware of the imminent dangers around these trenches and do you know how to protect yourself should you respond to one of these incidents?

Trenches can collapse without warning entrapping and surrounding a victim in seconds – making it impossible to breath. Most trench cave-ins occur in good weather, and it has been  reported that up to 70% of fatalities occur in trenches less than 12 ft deep and less than 6 ft wide. Failed trenches have a 100% chance of secondary collapse…it’s just a matter of time.

Just a few things to think about…

• 1 cubic yard of dirt moving 6 ft will reach an impact force equal to 45mph.
• 2-feet of soil on a person’s chest will create 700-1,000 lbs of pressure.
• 18-inches of soil covering a body exerts up to 1,800 to 3,000 lbs of pressure.

Here’s a recent fatality that occurred when workers were installing storm drains in Alamo, Texas.

OSHA has cited M&G Equipment Group Ltd., doing business as M Construction, with two alleged willful and six alleged serious violations following the death of an employee in March 2010 who was working in a trench installing a storm drainage system. “A company’s failure to protect its workers from cave-ins is simply unacceptable,” said Michael Rivera, OSHA’s area director in Corpus Christi, Texas. “If OSHA’s standards regarding proper trench sloping, shoring and shielding were followed, it is possible this tragedy could have been avoided.”

Serious citations were issued for failure to provide workers with safe egress when working in a trench, keep excavated soil a safe distance from a trench, use a properly designed trench shield, and ensure workers are trained on excavation hazards. A serious citation is issued when there is substantial probability that death or serious physical harm could result from a hazard about which the employer knew or should have known.

Proposed penalties total $53,550. OSHA standards mandate that all excavations 5 feet or deeper be protected against collapse. Detailed information on trenching and excavation hazards is available on OSHA’s Web site.

Whenever I go out into the field for a rescue stand-by job, I always take note of the attendant. I will always talk to them in order to try and gauge this person’s level of knowledge about confined spaces in general as well as the particular entry that is being made. Unfortunately, more often than not, I discover that this worker has very little experience or very little training in confined spaces. Most of these workers tend to be the “low-man” on the work crew and seem to just be “thrown” in to that position. A lot of the facilities and contractors seem to have the attitude that anyone can be the “hole-watch.” This can be the major ingredient in a recipe for disaster.

When OSHA created the Confined Space Regulation (29 CFR 1910.146) they included a list of the “roles and responsibilities” of the Entrant, Attendant and Entry Supervisor. A cursory glance at the responsibilities of the attendant paints a picture of someone who is acutely tied to the overall safety of the operation.

These are some of the highlights of the attendant’s duties:

• Know the hazards that may be faced during the entry, as well as the effects of those hazards
• Monitor conditions inside and outside of the space
• Call for the evacuation of the space in the event of an emergency or the detection of a prohibited condition

When you look closely at these duties, you’ll see that this is a lot more than just some “body” standing outside of the space. For example, in order to monitor the conditions inside a space, most attendants are handed a two- or four-gas air monitor and sent out to the space to “sniff” the air inside. The untrained or inexperienced “hole-watch” will likely not be aware of the numerous things that can affect the atmospheric testing results. Things such as the techniques used to calibrate the monitor, or the oxygen content of the air, or the concentration of certain gases can all skew the readings of a monitor. I have also seen, on at least two occasions, a ventilation fan being placed within a few feet of a bank of gas-powered welding machines. In one case, the carbon monoxide readings inside the space reached a high enough level to actually set off the alarms on the atmospheric monitor. These are things that unqualified workers are simply not going to know about.

Not only do the attendants out in the workforce need to be better trained, they also should be brought into the planning phase of the entry operation. The attendant should attend pre-job meetings as well as assist in the process of making the space safe for entry. In one entry that I witnessed about 10 years ago, a very well qualified attendant was present. The entry was into an underground vault that housed a large water main. The entrants were installing a new valve into the system. Because the attendant had helped shut down and isolate the space, he was familiar with the system in general. Once the repairs to the valve were completed, a call was made to re-pressurize the line in order to make sure there were no leaks present. The attendant ordered the entrants to exit the space while the pipe was brought up to pressure. The entrants argued that they needed to be there to tighten up any leaks that might develop, but the attendant was adamant that they leave the space. As the pressure in the line climbed higher, it ruptured and the entire vault filled with water in about 30 seconds. It happened so fast that no amount of pre-rigging for rescue would have saved the two entrants.

A well-qualified attendant can have a definite impact on the entire project. It is unfortunate that many times they are looked at as just some person standing outside the space – instead of a key component in the overall safety of the entry operation.

Additional Resources

• Attendant Safety Requirements Poster (pictured here)
• Confined Space Entry Checklist
• Common Causes of Confined Space Fatalities
• Limitations of Atmospheric Monitors

 

 

As with all rescue equipment, it’s extremely important to inspect your equipment before and after each use according to the manufacturer’s recommendations. Here are some tips from Skedco for inspecting your Sked Stretcher.

For the Sked Body: Do a visual inspection of the plastic. If there are cuts that go completely through the plastic (especially at the edges or the grommets), it should be   taken out of service and replaced. This is a very rare occurrence. If the plastic is wearing thin and preventing the Sked from retaining its shape, take it out of service.

Check all brass grommets. If they are badly bent or coming apart, they should be changed. This may also require sewing a new strap into it. Grommets can be replaced inexpensively by parachute riggers or any awning shop. When it is done, be sure the grommeting tools do not cut the inside of the grommet. Grommets that are sharp inside can cut webbing or rope.

Check all straps for broken stitching, discoloring (usually white), and fraying. If straps are badly frayed, discolored or if ten (10) or more stitches are broken, replace the straps.

Horizontal lift slings: Check for excessive wear, broken stitches or severe discoloration. If these conditions are found, replace the slings.

Vertical lift slings (3/8 static kernmantle rope): Check for severe discoloration and soft or thin spots. Thin spots that are soft indicate damaged core. If found, cut the rope at that point and take it out of service.

All other webbing products should be inspected in the same way as the slings and Sked straps.

The carabiner should work smoothly when the gate is opened and closed. Check for alignment. Check the hinge pin for looseness. The lock nut should work smoothly without hanging up at any point. Failure at any of these points requires replacement. A poorly functioning carabiner should be broken or destroyed to prevent others from using it by mistake.

If you have any doubts, call Skedco for assistance.

A recent accident involving a worker who fell from height inside the mono-tube of a water tower under construction, underscores the need to have a thorough understanding of Fall Protection systems and practices required by OSHA while undertaking hazardous work activities. It also emphasizes the importance of preplanning for rescue. Be sure to read additional comments from Roco Chief Instructor Pat Furr at the end of the article. Thanks to Dr. Skip Williams for submitting this story.

EAST WINDSOR, NJ… A worker fell nearly 50 feet to his death inside a new water tower under construction in a rural area of the township, police said. The 56 year-old man, whose name police did not release, was on a scaffold inside a tubular portion of the tower when he fell, landing on a solid floor 30 feet above the bottom of the structure. There was no water inside, and the worker was wearing a full body harness, said East Winsor Volunteer Fire Company No. 1 Chief Kevin Brink, one of the first responders on the scene. Mounting a ladder and coming up through a trap door in the floor where the man fell, Brink saw the man unconcious, unresponsive and bleeding. “I tell you this: I’ve seen worse people living,” he said. “To me, he was considered living until the paramedics pronounced him.”

The tower he was working on rises about 80 feet above the trees and farmland on Millstone Road. The familiar bubble-shaped cap that will hold water is not installed yet, and the structure yesterday looked much like a massive vase, with a dull pyramid for a bottom and a cylindrical tube mounted on top. A large crane had four metal lines grasping the top of the cylinder, and smaller cranes and trucks dotted the mud and gravel lot set back from the roadway. The victim, an employee of New Castle, Del.-based CBI Services, fell around 10:30 a.m., and was working near the top of the cylinder, Brink said. Fellow workers called 911, and police, firefighters and medical personnel rushed to the scene. The man’s colleagues entered a door at ground level and used ladders to get through the door at the bottom of the cylinder, where the man lay.

As firefighters donned equipment and prepared a basket to rush the man to a waiting ambulance, paramedics entered the structure and pronounced the victim dead. “We were just called out there for the actual rescue, unfortunately the person didn’t make it and it turned into a recovery,” Brink said. Police examined the body before firefighters put it inside the basket and lowered it out of the tower using a rope system, Brink said. By noon, the man’s body was out and ready to be turned over to the medical examiner.

A spokesperson for CBI Services would only say that an investigation is under way. Along with police and the medical examiner, both the Mercer County Prosecutor’s Office and OSHA responded to the scene, police said. “We’ve never really had any type of industrial accident out there,” Brink said. Unfamiliar with the layout of the tower, Brink said he initially was not sure if he would have to bring the company’s 100-foot ladder truck to reach the heights of the structure. “If he was stuck at the top, we were already starting to think about that,” he said.  Alex Zdan, Staff Writer/ New Jersey Times

NOTE:  While we were not present at the scene and don’t know all the details, here are some general comments from Chief Instructor Pat Furr concerning fall protection safety.

This incident took place while work was being done from a scaffold erected inside the tower. The worker fell from his work position and came to rest on a solid platform between the scaffold level and the ground. He was wearing a full body harness for body support as part of his personal fall protection system. However, this begs the question, “Why bother wearing a harness if the complete fall protection system is not employed?”

A complete personal fall protection system, which would be considered an active system, requires all of the components required by OSHA in order to be considered an effective/compliant means of personal fall protection. The harness is just the start. In addition to the harness for body support, there needs to be a connector attached to the appropriate point of the harness.

For fall restraint, a static lanyard can be used and connected to the rear or front waist belt attachment points of the harness (not the side attachment points); or, if desired, a body belt, or the dorsal attachment point of the full body harness. The lanyard must be adjusted to a length that does not allow the worker to fall from any exposed edges. This restraint lanyard does not need an energy absorber. If there is any potential that the worker may fall, then the lanyard must have an energy absorber that limits the impact forces at the harness to no more than 1,800 pounds. It must also limit the workers freefall to 6 feet or less.

An alternative is to use a Self-Retracting Lifeline (SRL). The third component of a personal fall protection system is a suitable anchor. The anchor point must be able to withstand a 1,000 pound force without failure for fall restraint, and a 5,000 pound force if used for fall arrest. These anchors can be as light as two times the anticipated forces if designated by a qualified person. Only one worker can be attached to the anchor point unless the minimum breaking strengths are multiplied by the number of workers using the same anchor point.

To review, the three physical components of a personal fall protection system are: (1) body support, (2) connector, and (3) anchor. For a fall arrest system, a fourth component is required, and that is prompt rescue.

This worker was on a scaffold. If the scaffold was completed with a green tag affixed, then it would have had standard guard rails to provide a passive fall restraint system and a harness would not have been necessary. If the scaffold was not completed and green tagged, then a personal fall protection system would be required.

Too often we encounter workers who are either unaware of the requirements to ensure safety at height – or choose to ignore the safety requirements that would most likely save their life or prevent serious injury. Bottom line…the use of a harness without completing the entire system only comprises 33% of the system which equates to 0% fall protection.

Recently, we had a client ask about these specific uses of the Sked-EVAC tripod. Here’s what the manufacturer (Skedco) had to say…

“Is it safe to attach a ‘change of direction’ onto the lower end of one of the tripod legs?”

“No!” According to Bud Calkin, the manufacturer of the tripod. He continues in saying that it is unsafe to pull horizonally on one leg of any tripod because it may cause the tripod to shift and destabilize the system. Skedco recommends the use of a separate anchor in this case.

“Is it acceptable to use the tripod as an ‘A’ frame and lean it over the edge?”

Yes, if you rotate the tripod feet so that the pointed ends of the feet are down and supporting the tripod. According to Skedco, if you are working on a surface that would allow the feet to slip, you must tie or secure the feet in such a manner that they cannot slip and allow the system to collapse.

By using any tripod that has swiveling feet in that configuration (bipod) with the feet flat on a hard surface, you will experience uneven pressure on the edges of the feet as it is leaned over the edge. This could possibly damage the feet because of the angle at which they are turned (i.e., the feet are pointed toward the center of the triangle formed by the tripod). This angle places the weight of the tripod onto the edges of the feet and that is not what they are designed for.

Skedco also says that when using the Sked-Evac tripod as an “A” frame, it is necessary to attach ropes to the two unused anchors that are attached to the head. You can do this by using carabiners. Tie the tripod back in the opposite direction from the load that is being hoisted. This will prevent the tripod from leaning too far over the edge and causing the system to collapse. Check all rigging and attachments for safety prior to lifting any load, especially a human load.

The improper use of any tripod is very dangerous and could be fatal. It is the responsibility of the user to get proper training prior to using a tripod or any other rescue equipment.