Innovative rescue
Published: 01 April, 2007
At least 65% of all fatalities during trench rescue operations are would-be rescuers. Secondary collapses cause many rescuers to be severely injured; though casualties are rescued alive from trenches, many die afterwards of hypothermia and crush syndrome.
At least 65% of all fatalities during trench rescue operations are would-be rescuers. Secondary collapses cause many rescuers to be severely injured; though casualties are rescued alive from trenches, many die afterwards of hypothermia and crush syndrome. The average time of a rescue is prolonged by hours, because of the time it takes to the dig the victim out with buckets and shovels
Dave Adler, a firefighter from Illinois, invented the Rescue Vac about five years ago for the construction industry, but decided that this could prove an excellent tool for the fire and rescue sector.
This system consists of a series of extension hoses and nozzles which can be connected to a vacuum truck in order to suck debris, sludge or even contaminated atmospheres out of trenches, silos, structural collapse situations and many other rescue scenarios.
“The typical rescue time for trench rescues is six to nine hours,” says Dave. “Rescue Vac technology will reduce the rescue time from nine hours to just 45 minutes.”
Reducing the time taken over rescues means the chances of crush syndrome and hypothermia are diminished. The vacuum nozzle enables the rescuers to rapidly open up the area in front of the victims’ chest to facilitate respiratory effort.
Rescue Vac comprises two parts. The first consists of specially-designed hoses, safety devices and nozzles which attach to a vacuum truck. The second part is an air knife.
“The vacuum truck on its own, just sucks debris and soil from the surface. This is what makes Rescue Vac so attractive for the firefighters. They do not have to own a $25,000 dollar vacuum truck, they just need the Rescue Vac kit.”
The kit contains a lightweight 10-foot suction hose, a 20-foot suction hose, plus specially-designed vacuum holes and several vacuum relief devices.
During operations, a member of the rescue team guards a tethered line connected to the safety relief valve. If anything happens he can close the vacuum off immediately or can reposition the nozzle, so no vacuum is created.
“There are certain procedures that you need to follow. We have several kinds of nozzles for the system. It uses a short nozzle, about 18” long, and a medium-sized nozzle, what we call the four-footer, which can be used in a standing position.
“Let’s say you have a very deep trench, the hose comes down and you have a man standing down the bottom of the trench. On this nozzle there are special eyehooks; these enables the user to suspend the hose from a frame ladder system. It also features a mechanical advantage system.”
LACFD and FDNY were the first Departments to experiment with Rescue Vac. The most popular use is currently for the 10.5 nozzle. It features special skid plates and eyehooks. It allows the rescuer to work from the edge of the trench and slide it down. The unit means there is no need to commit rescue personnel in the trench.
Dave has also used this technique in trenches of over 15-feet deep, where he suspended 10-foot hose, which also has eyehooks about two feet up from the end.
The air knife is fed by an air compressor. The kit contains two different kinds. The larger airknife has strength of a 100psi and the smaller air knife has a pressure of 185cfm. The speed of the air coming out is around Mach 2, which is around 1,400 miles an hour. When you are going back and forth it only exerts a pressure of 11 to 14 pounds, says Dave. That airflow fractures the soil and the smaller airknife allows the rescuer to remove rubble and soil away from the victim.
The larger one – 330 cfm – is used for hard, compacted soil. Dave comments: “We have to stay three or four feet away from the victim with that one. In a case involving a bad cave-in or when we have to ‘cut corners’, instead of taking hours, this allows us to do it in two minutes.
“The air knife aerates the soil underneath the vacuum nozzle. We are not only using this for soil, but also for sand, landslide debris, granular products in silos and hoppers and some rescuers are even using it to extract contaminated air from confined spaces. This product can be used in trench rescue, confined space rescue, structural collapse,” he concludes.
It is clear this new product development has important ramifications for professionals working in the confined space and buried rescue sector, and FIRE & RESCUE hopes to bring you more details on this in due course.
NT bags for USAR work
What do you do when ordinary 8-bar pneumatic lifting bags just won’t do the job?
Jan Pieter Maarschalk of RESQTEC Zumro B.V., outlines new strategies involving the RESQTEC NT Bag Series.
Jan Pieter tells F&R:
“The NT bags are quickly becoming the new standard in lifting. Imagine you’re faced with a collapsed building you need to create an access tunnel into - or perhaps a bus accident, wrecked train or even a medium pickup truck crash. When time is critical, how do you lift a mass without bringing in a heavy crane?
“Thanks to unique design and technology, NT bags combine height with capacity - in fact they offer over 600% more capacity than you currently find in 8-bar bags.”
NT bags are currently used in both RTA and USAR operations by teams such as THW in Germany, New Dimensions in UK and by Dutch USAR teams. NT bags can be connected to each other with a torque-resistant quick connector, enabling rescuers to lift heavy loads up to 1.5 metres high. They operate at a pressure of 10 bars, and have a safety factor of more than 4, making them the safest bags available, says the manufacturer.
“Almost all international rescue teams already use the NT bags, and most countries they are already the standard. Users tell us their biggest advantage is ease-of-use and so they get deployed whenever circumstances arise.”
An added advantage, he says, is that NT bags work together with RESQTEC’s ProFix stabilisation system. Capable of being operated mechanically as well pneumatically, ProFix can cope with loads of up to 10 tons. The ProFix range has many accessories and modules, enabling rescuers to use it for shoring, stabilising and trench rescue. More information? Visit: www.resqtec.com
