Non-Viable Worker in a Tree: Case Study
A HIV and Hepatitis C positive arborist cut their brachial artery with a chainsaw 50’ up a tree that they had topped.
As the arborist was attached via three lines to the tree (including a cable) the first in crews were unable to recover the body. As such, the Technical Rescue Unit (Tech Rescue) was dispatched. Tech Rescue was conducting recruit rescue training at the time of the incident and responded from the training, with recruits in tow, to the incident.
Upon arrival of the Tech Rescue we saw a worker, who had bled out, suspended in a tree.
The worker was visible from all directions as the worker was above the rooftops of the homes.
The first in crew had used a 40’ tormentor pole ladder to try and reach the worker. They had contact, however could not recover.
The tree was topped about 1.5’ above the worker. The tree was in the backyard of a private residence and ladder apparatus access was not an option.
The tree and surrounding ground was soaked in blood. There was an elementary school within sight of the incident.
On scene was the first in Engine Company and the Ladder Company. The District Chief had arrived as well as Police, Coroner and Ambulance service.
The first in Engine Company was from the Technical Rescue Hall and had trained Tech Rescue staff. There was also a Technical Rescue Instructor as well as 7 or 8 recruits.
Plan of Action
In discussions with the Incident Commander we ruled out cutting down the tree or trying to cut all of the ropes.
While the Rescue Team Leader felt this was the safest course of action, the IC ruled that the perception of such action would be a media disaster.
A plan was then formed to dress one Tech Rescue Firefighter (Rescue 1) in full PPE (tyvex suit, gloves, goggles – full precautions) and have them climb the 40’ ladder. The ladder would be tied to the tree and Rescue 1 would climb to the top rung of the ladder with a lanyard for safety.
At the top, Rescue 1 would attach themselves to the ladder and the tree. The tree attachment was with a choked Omni sling.
Using a combination of lines, slings and the ladder, Rescue 1 would then rig a high point on with another choked Omni sling above the worker. Rescue 1 would then use a B Suit (screamer suit) to package the worker, as the workers’ 3 lines went to different points on their harness.
The ground crew would then raise the worker, allowing Rescue 1 to unhook/cut the lines and the worker to be lowered to the ground.
Rescue 1 harnessed up and with additional carabineers, slings and a B suit, ascended the ladder.
The ascent of a vertical aluminum ladder on a blood soaked scene was trickier then imagined. For safety this climb was completed slowly and with as many attachments as possible.
Once at the top of the ladder, Rescue 1 secured themselves to the tree with slings.
With only 1.5’ of tree left above the worker, and the workers high point also rigged in this space, creating a high point was difficult. With the worker and workers rigging taking up around 8’ of vertical distance, this further complicated rigging of the high point.
Rescue 1 had to try and bypass the worker and then use the Omni strap in a choker configuration to maximize the available lift in the 1.5’ that was available. Rescue 1 then placed the worker into the B suit.
Once the high point was rigged and the patient packaged, the ground team raised the worker in order to provide some slack (max 1’ raise) in the workers lines. Even with this slack it was very difficult to disconnect the three lines. A combination of cutting ropes and carabineer disconnection was used.
Once the worker was clear of the lines, Rescuer 1 climbed down and the ground team lowered the worker. From Rescue 1 starting to climb, to the worker reaching the ground, was just over an hour.
There were many challenges that arose on scene.
Having the worker stuck in an area publically viewed (including a nearby school) was challenging.
Rescuers were put at greater risk (exposure to blood borne pathogens) since the worker could not just be cut out of the tree (ropes or tree), due to public perception.
There was also an unspoken urgency with the recovery due to the sight of the worker in the tree. This was never mitigated and remained a factor through out the recovery.
The lack of anchors above the worker was challenging. As the worker had already topped the tree above, there was only a 1.5’ area where Rescue 1 could rig. The worker’s two-line system was also rigged through a high point in this area further limiting the space.
Rescue 1 used a 5’ Omni sling in a choker configuration, and for the high point utilized the smallest pulley and carabineer we had available.
The vertical space occupied by the worker in a tight environment was challenging. Rescue 1 had to climb on the worker in order to get past.
Once the high point was installed, Rescuer 1 could sit in our rope system in order to bypass the worker (disconnecting after rigging and packaging was complete).
Packaging the patient into the packaging device was challenging. As the worker had three lines coming off of their harness in two separate directions, securing the B suit was challenging. The B suit was packaged as well as possible, however due to the lack of working space and the tightness of one of the lines, the packaging had to be altered by the use of another sling to match the D rings on the B suit. The worker being attached by three ropes was challenging. The worker was on a two-line system and a cable choker. The cable choker proved to be the most challenging part of the rescue. The cable was to loose to cut and with the patient attached to it, difficult to raise. It had to be unhooked, requiring the worker to be raised a foot.
The worker was successfully lowered to the ground (recovered). The worker was non-viable and vital signs absent upon arrival.
There are many lessons that can be taken from this recovery.
First and foremost, no one (or very few teams) practices for a recovery. Recoveries are different then rescues. Urgency is different. Other factors such as perception, cost of equipment, and tying up of numerous resources become an issue. From our experience we were expected to do the same, however with less. The risk vs reward model also becomes skewed.
Another take-away for our team was in regards to training. Not only to add more variety into our rescue training, however, to become very skilled with the equipment we had. At the time we extensively used Omni slings. Everyone knew how to rig them for daily use. When we looked at altering this use on site, questions arose. What is the breaking strength in a choker configuration? While we had been taught to not use the last hole in an Omni – when we have no choice, what does that hole break at? To summarize we needed to become more fluent and proficient in all aspects of our equipment use. Not just the regular uses we were all trained in.
Another take-away was creating more variety in our training. There are many operations that we do not train for and there is no way we can guess what the next call will bring. Adding variety in the training (new scenarios, new locations, new parameters) can provide your team with varying experiences and rigging practice that just may come in useful at the next call.