Hydraulic rescue tools are used by
emergency rescueEmergency services are organizations which ensure public safety and health by addressing different emergencies. Some agencies exist solely for addressing certain types of emergencies whilst others deal with ad hoc emergencies as part of their normal responsibilities...
personnel to assist
vehicle extricationVehicle extrication is the process of removing the vehicle from around a person that has been involved in a motor vehicle accident, when conventional means of exit are impossible or unadvisable. A delicate approach is needed to minimize injury to the victim during the extrication...
of crash victims, as well as other rescues from small spaces. These tools include
cutters,
spreaders, door busters and
rams. They are popularly referred to in the English speaking Commonwealth nations, as well as the USA and Canada as
Jaws of Life, a trademark of
Hurst PerformanceHurst Performance, Inc. of Warminster Township, Pennsylvania, manufactured and marketed products for enhancing the performance of automobiles, most notably for muscle cars.-Products:...
, Inc. The Jaws of Life was first used in 1963 as a tool to free race car drivers from their vehicles after accidents.
Hydraulic rescue tools are powered by an hydraulic
pumpA pump is a device used to move fluids, such as liquids, gases or slurries.A pump displaces a volume by physical or mechanical action. Pumps fall into three major groups: direct lift, displacement, and gravity pumps...
, which can be hand-, foot-, or engine-powered, or even built into the tool. These tools may be either single-acting, where hydraulic pressure will only move the cylinder in one direction, and the return to starting position is accomplished using a pressure-relief valve and spring setup, or dual-acting, in which hydraulic pressure is used to both open and close the hydraulic cylinder.
History
Previously rescuers often used
circular sawThe circular saw is a machine using a toothed metal cutting disc or blade. The term is also loosely used for the blade itself. The blade is a tool for cutting wood or other materials and may be hand-held or table-mounted. It can also be used to make narrow slots...
s for
vehicle extricationVehicle extrication is the process of removing the vehicle from around a person that has been involved in a motor vehicle accident, when conventional means of exit are impossible or unadvisable. A delicate approach is needed to minimize injury to the victim during the extrication...
, but these suffered from several drawbacks. Saws can generate
sparksEmbers are the glowing, hot coals made of greatly heated wood, coal, or other carbon-based material that remain after, or sometimes precede a fire. Embers can glow very hot, sometimes as hot as the fire which created them...
, which could start a fire, create loud
noiseIn common use, the word noise means any unwanted sound. In both analog and digital electronics, noise is random unwanted perturbation to a wanted signal; it is called noise as a generalisation of the acoustic noise heard when listening to a weak radio transmission with significant electrical noise...
, which could
stressStress is a term in psychology and biology, borrowed from physics and engineering and first used in the biological context in the 1930s, which has in more recent decades become commonly used in popular parlance...
the victim, and are often slow. Alternatively, rescuers could try to pry open the vehicle doors with a
crowbarA crowbar, a wrecking bar, pry bar, or prybar, or sometimes a prise bar or prisebar, and more informally a jimmy, jimmy bar, jemmy or gooseneck is a tool consisting of a metal bar with a single curved end and flattened points, often with a small fissure on one or both ends for removing nails...
or
Halligan barA Halligan bar is a special forcible entry tool commonly used by firefighters and law enforcement. It was designed by and named after Hugh Halligan, a First Deputy Fire Chief in the New York City Fire Department, in 1948...
, but this could compromise the stability of the vehicle, injure the victims further, or inadvertently trigger the airbags of the vehicle.
In comparison, hydraulic spreader-cutters are quieter, faster, and more versatile: they can cut, open, and even lift a vehicle.
Jaws of Life is a now trademarked line of tools originally developed by
Hurst PerformanceHurst Performance, Inc. of Warminster Township, Pennsylvania, manufactured and marketed products for enhancing the performance of automobiles, most notably for muscle cars.-Products:...
, located on Jackson Road in Warminster, Pennsylvania. Hurst Performance began to export parts to a European company to avoid import duty. In partnership with Zumro resQtec for use in
auto racingAuto racing is a motorsport involving the racing of cars for competition. It is one of the world's most watched televised sports.-The beginning of racing:...
, with Hurst targeting the American market and resQtec targeting the European market. The hydraulic spreader was originally developed in 1972 by Tim Smith and Mike Brick, who later developed a cutter and a hydraulic ram. When an occupant is trapped the tool is used to pry or cut the car to remove the occupant. It takes about two minutes to take the roof off a car. Mike Brick coined the phrase "Jaws of Life" after he observed people saying that their new device "snatched people from the jaws of death." Later Brick went on to develop a single rescue tool that could perform all the functions of rescue — push, pull, cut and spread. His patent for this unique design eventually led to the Phoenix Rescue tool, which incorporates his design to this day.
Other manufacturers (including
HolmatroHolmatro, an Hydraulic equipment manufacturer with its roots in the Netherlands. Formed in 1967, it was set up to supply hydraulic lifting and rescue tools to the industrial and fire and Rescue market. The Holmatro line of products includes high pressure hydraulic lifting, cutting, and spreading...
and Lukas, amongst others) make equivalent tools.
Cutter
The cutter is a hydraulic tool which is designed to cut through metal — a hydraulically powered shears. It is often called a crab-cutter, owing to the shape and configuration of its blades. Sometimes specified as to its capacity to cut a solid circular steel bar, these are most commonly used to cut through a vehicle's structure in an extrication operation. Cutter blades are replaceable, and blade development progresses as vehicle technology progresses in order to be able to cope with the new car protection technology.
Spreader
A spreader is a hydraulic tool designed with two arms which come together in a narrow tip, and which uses hydraulic pressure to separate or spread the arms. The tip of the tool can be inserted into a narrow gap between two vehicle panels (such as between two doors, or between a door and a fender) — when the tool is operated, the arms are opened, pushing apart the metal in the panels. Spreaders may also be used to "pop" vehicle doors from their hinges.
Spreader-cutters
Whilst a cutter or spreader tool is designed for a particular application, a combination tool, or combi-tool as popularly referred to by the fire department, is also available which combines the cutting and spreading functions of separate tools into a single tool. In operation, the tips of the spreader-cutter's blades are wedged into a seam or gap — for example, around a vehicle door — and the device engaged. The hydraulic pump, attached to the tool or as a separate unit, powers a
pistonA piston is a component of reciprocating engines, reciprocating pumps, gas compressors and pneumatic cylinders, among other similar mechanisms. It is the moving component that is contained by a cylinder and is made gas-tight by piston rings. In an engine, its purpose is to transfer force from...
that pushes the blades apart with great force and spreads the seam. Once the seam has been spread, the now-open blades can be repositioned around the metal. The device is engaged in reverse and the blades close, cutting through metal. Repeating this process allows a rescuer to quickly open a gap wide enough to pull free a trapped victim. The blades can spread or cut with a force of several
tonThe ton is a unit of measure. It has a long history and has acquired a number of meanings and uses over the years. It is used principally as a unit of weight, and as a unit of volume. It can also be used as a measure of energy, for truck classification, or as a colloquial term.It is derived from...
s or kilonewtons with the tips of the blades spreading up to a meter.
This operation can also be performed by dedicated spreading and cutting tools, which are designed especially for their own operations and may be required for some rescues. These tools sometimes have lower capabilities when compared to the dedicated tool (e.g. a smaller spreading range) but may be useful where space is at a premium on fire and rescue vehicles, or when the budget does not allow for a separate cutter and spreader tool.
Many manufacturers utilize the body of their dedicated cutting tool for the combination tool. Specially engineered combination blades that are designed to spread and cut are used on the cutter body. If the end user decides later to add a separate cutter and spreader, the blades of the combination tool can be changed to make it a cutter only.
Rams
Rams are used far less than spreader-cutters in auto rescues; nonetheless, they serve an important purpose. There are many types and sizes, including single-piston, dual-piston and telescopic rams. Sizes commonly vary from 50.80 cm (20") to 178 cm (70") (extended). Rams use more hydraulic fluid during operation than spreader-cutters, so it is essential that the pump being used have enough capacity to allow the ram to reach full extension.
Power
The tools operate on the basis of hydraulic fluid pressure of up to 720 bar (10,000 psi), which must be provided from a power source. At present, there are three different means of generating the pressure. The most commonly used source is a separate power unit, a small petrol (gasoline)
engineAn engine or motor is a machine designed to convert energy into useful mechanical motion. Heat engines, including internal combustion engines and external combustion engines burn a fuel to create heat which is then used to create motion...
connected to an hydraulic pump. The hydraulic fluid is pressurised in the pump, and conveyed in a hose under pressure to the tool.
Alternative power sources are a small electrical pump in the tool powered by a heavy duty rechargeable battery, and a hand- or foot-operated pump also connected to the tool directly. These are useful for lighter-duty use and do not require the storage space taken up by the separate power unit and associated lengths of hose.
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