THE USE OF CRANES AND HEAVY EQUIPMENT IN RESCUE AND HAZ MAT

THE USE OF CRANES AND HEAVY EQUIPMENT IN RESCUE AND HAZ MAT

BY MIKE SHANNON

Cranes and other heavy equipment such as loaders, trackhoes, and backhoes have a have a significant place in today`s fire service technical rescue, US&R, and heavy rescue operations. In the hands of proficient operators, cranes and other heavy equipment can shorten rescue/recovery times while exposing fewer rescuers to site dangers. They can increase the effectiveness of a rescue or recovery operation and can perform tasks that we once looked to wreckers to provide, such as moving and lifting heavy objects, large vehicles, and sections of collapsed structures, that could never be safely performed by a wrecker. Although wreckers can pull and bind a vehicle or container, a properly rigged crane can cradle the same object and carefully move it.

We use wreckers to upright objects, and they do in many cases. Many wrecker companies have acquired lifting bags to lift. Many of us who have worked accidents involving large vehicles or incidents involving large objects have witnessed strap, cable, or chain failures. In some cases, the object did something that wasn`t anticipated. Many times, the wrecker was pulling on the object, fighting gravity and friction, thus overloading the connecting devices, creating hazards and causing failures.

I gained respect for and appreciation of the capabilities of cranes and other heavy equipment while serving as the forward rescue operations chief at the Alfred P. Murrah Building in the Oklahoma City Bombing in April 1995. When the equipment operators were allowed to work at their own pace with as little interference as possible, they cut our operational time and accelerated recovery.

HEAVY RESCUE AND HEAVY CONSTRUCTION SKILLS ARE SIMILAR

In many cases, when rescue workers train in heavy rescue skills, they mimic what heavy construction workers do daily. Large construction companies lift/haul, breach/break, and shore regularly. We could never provide the skill or experience that riggers and heavy equipment operators possess–even though we go to great lengths to develop, train in, and practice construction skills directed at rescue and recovery–because we have limited time to devote to such training.

A 90-pound jackhammer in the hands of the best-trained rescue worker is no match for that same tool in the hands of an experienced construction worker who uses it daily or weekly. Better yet, instead of a 90-pound jackhammer and an experienced construction worker, place the jackhammer on the front of a tractor with an experienced operator. Things will happen fast, to be sure.

During the Murrah Building operations, we became very well acquainted with Midwest Wrecking and Allied Steel equipment and personnel. Watching what they could do and seeing their resources and equipment, which no fire service can buy, maintain, or become proficient in operating, was enlightening. Tasks they do without thinking are tasks we struggle with and don`t get right all the time. In a rescue or haz-mat incident, we seldom have the flexibility to make mistakes or to experiment.

CRANE USES AND TYPES

The most common use for cranes today is in a collapse situation, but cranes and heavy equipment can have much larger roles if we take the time to learn about them. The cranes that have practical applications for rescue work are the truck and the RT (rough terrain) cranes.

Truck Cranes

There are two basic groups of truck cranes: hydraulic and conventional or lattice. Truck cranes have good mobility. The hydraulic crane, using its main boom, can literally work miracles if it is able to get close to the item to be picked up (the pick), such as on a highway. At a collapse site, however, where the incident is of long duration and long reaches and heavy picks are needed, the lattice truck crane is more efficient. It can get to the site in a relatively short time and can pick more and reach farther because the boom weighs less than a massive hydraulic boom.

Rough Terrain (RT) Cranes

RT cranes, which are usually hydraulic, have several characteristics that make them suited for rescue operations. They have the engineered ability to travel with the object they pick. They can leave a paved surface and get to locations other cranes could never work. A small (18-ton) RT crane can pick up a full-size automobile with ease and safely carry it to an area that is better suited for work. Or it could pick up the automobile, carry it, and then raise it to an elevated position for better occupant extrication. RT cranes also have a low profile and can access off-the-road locations such as dirt roads with overhanging trees, creeks, and the like.

Cranes can also be very helpful in incidents involving tractor-trailers. A crane was of enormous help here in Oklahoma City when a truck rolled over on top of a car on an interstate bridge. The occupants were seriously trapped. Wreckers were called and worked for 112 hours before heavy rescue members requested a crane. The crane`s response time, including raising the trailer off the car (done by a 50-ton lifting capacity machine) and holding it until a 70-ton machine arrived to set the truck-trailer on the ground, took 30 minutes. It took an additional 15 minutes for the larger machine to arrive and set the truck-trailer down softly on its tires. Total operation time was 45 minutes, including response, setup, and rigging. Of course, several teeth-gritting conversations with the wrecker operators were necessary; they said the lift could not be done the way the crane people said it could.

Our challenge is to become informed enough to recognize when and how to use cranes: How can we prepare the site for them, and how can our personnel assist them? Many of our people have worked with the operators to learn the answers to these questions. If rescuers learn how to flag (use hand signals to direct operators) a crane or piece of heavy equipment, the companies will have to mobilize fewer workers, thus speeding up their response time. The quicker we recognize the need for a crane at an incident site, the better the crane`s response time will be and the better prepared the site will be for it when it arrives.

SOME CRANE FACTS

The following are some facts that commonly apply to working with cranes.

For all cranes except the overhead crane, the heavier an object is, the closer to the center pin (the center pivot on which the crane revolves) it should be. When a crane is unstable because of weight, get the weight closer to the center pin.

A crane is rated by the maximum weight it can pick (max pick). Thus, a 50-ton crane can lift a maximum of 50 tons. This max pick is usually over the rear of the crane diagonally on the outrigger (see diagram on page 150). In many cases, the maximum weight is rated by lifting it off the deck of the crane itself.

The weight of the boom`s components, such as the pill (weighted hook), cable, jib (boom extentions), and main hook (block), is subtracted from the maximum lifting weight.

When making the maximum pick, the object may be rotated only a few degrees. In other words, the crane may be able to get close, sling the load, and lift it but won`t be able to swing it to the side. Always consult the load chart to determine which type of crane should be used in a specific rescue operation.

Operating from any point other than over the crane`s rear is likely to reduce the maximum weight the crane can pick, especially if the crane can spot only with the pick over the side.

The farther away the pick is from the center pin, the less weight can be lifted. A foundation is necessary. A Link-Belt HC 258 200-ton truck crane when rigged with maximum boom (stick) and all the counterweights to lift capacity, weighs 390,000 pounds before it picks up anything. In that configuration with its max pick, it has a total weight of 426,400 pounds (213 tons), all sitting on five fully extended outriggers. A crane like this was used in Oklahoma City and was respectfully referred to as “Mother.”

Equipment footing, the surface or terrain on which the crane sits, is important for stability and safety. The crane is supported solely on the outriggers. Usually, all the wheels are off the ground. Although a crane can lift a 250-ton locomotive or a fully loaded semi, the foundation (the footing of the crane) may become overloaded, and the machine will tip. The weight that was spread over a large area is now concentrated in a comparatively small area. When a crane, other type of heavy equipment, or wrecker is working on a bridge, which is designed to handle a distributed load, overloading or side loading can be catastrophic.

For the big jobs–tractor-trailer accidents, collapses, and other incidents that involve objects larger than our equipment can handle–we should consider heavy equipment. As firefighters we believe, “Big fire, big pressure.” Why not employ the same principle in heavy rescue–“extra heavy object, extra heavy equipment”? The time spent waiting for the crane to arrive will be made up once it arrives. Spend the waiting time looking for the best location for setting up the crane and determining information such as the weight of, distance to, and destination of the pick(s). This information will also determine the most appropriate type of crane for the job.

TRAINING INDICATED

The fire service should work with the riggers and operators to make the incident go faster. The better both groups can work together, the faster the incident will be concluded. Of course, that means training together, getting to know each other, and learning how to help each other realize the desired objectives of the operation.

Flagging, for example, helps you to understand what`s going on and places you in the middle of the operation. If you know flagging, you`ll understand what is needed to get an object where you want it. Flagging is the closest thing to operating the crane. Understanding the operations and the limitations of a crane–understanding a crane`s load chart–takes a bit more time. But the benefits can be enormous. It may sound troublesome, but it isn`t more so than looking at a manual on fire streams or hydraulics for the first time. As far as technical rescue, US&R, and heavy rescue are concerned, heavy equipment is a must, and team members should be aware of what they can contribute to the efficiency and safety of these operations.

Local construction, steel, and crane rental companies can help you understand a crane`s load chart, assist in setting up the crane, learn which types of cranes are available in your area, become acquainted with basic rigging tools and principles, learn basic flagging signals, and–most importantly–gain hands-on experience working with a crane and other heavy equipment. Knock on the doors of the crane and equipment companies, and persuade them to join your efforts. Then make these resources part of your preplan. n



(Left) This Grove 70-ton hydraulic truck crane can travel up to 65 miles per hour, reducing waiting time for rescuers at the incident site. Computer enabling and new sensitive, smooth hydraulics (right) make it efficient and safe. As an example, if the crane attempts to pick up a load (pick) that exceeds its safe operational envelope, the computer will not permit the pick. (Photos courtesy of Allied Steel.)



(Left) A lattice truck crane lifting an Air Force plane that weighs some 180 tons. (Right) This 70-ton hydraulic truck crane is lifting a beam off a delivery truck. The driver was killed in the accident.


An 18-ton Allied Steel rough terrain (RT) crane. The RT crane, usually hydraulic, can travel with the object it picks. It can leave the paved surface and get to locations many other cranes cannot. Its low profile enables it to enter off-the-road locations such as dirt roads with overhanging trees, creeks, and the like.



All cranes have on the back a sign indicating the distance to the center line of rotation (CL). Note the line above the sign. By measuring the distance from the object to be picked to this sign and adding the distance on the sign (9 ft.-11.06 in. here), the operator can determine how far the object is from the center pin (the pivot on which the crane rotates). The closer to the center pin the object is, the more stable the operation.



Knowing the basic hand signals for crane operations is vital to safety and efficiency. Interchanging the signal for “hoist” (left) with the signal for “boom up” (right), for example, can present hazards for all on-scene.

n MIKE SHANNON, a retired 21-year veteran of the Oklahoma City (OK) Fire Department, has served on the OCFD Haz Mat Unit and special operations chief for the past 15 years. He is a haz-mat technician, specialist, and on-scene incident commander. He served as rescue operations chief at the Oklahoma City Bombing, in charge of operations within the Alfred P. Murrah Federal Building for 280-plus hours. He is a lead instructor at the National Fire Academy and the Federal Emergency Management Agency, an associate staff member and course developer for the U.S. Department of Transportation–Transportation Safety Institute, and a course developer for the NFA course “Hazardous Materials On-Site Practices.” The four years he served with nuclear/biological/chemical warfare in the U.S. Navy led him to the hazardous-materials area.

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