Preplanning for Machinery Entrapments

BY STEVE SHUPERT

A machinery entrapment is among the most challenging of rescues. It tests the skills and creativity of even the most competent rescuers. This type of incident necessitates coordination among fire/rescue; the hazardous materials staff; EMS personnel; and civilians who have special knowledge about the machinery, tools, and equipment. This type of incident often happens in locations with limited access, poor lighting/ventilation, and excessive dust and debris. Some skills needed are based on vehicle rescue and rigging. Some incidents occur in confined spaces, trenches, agricultural areas, sewage plants, and industrial environments.

Types of machines that trap victims vary. They include conveyor belts; escalators/elevators; drills/augers; blenders; presses; robots; power takeoff shafts (PTO); and pneumatic, electric, and hydraulic equipment. Scene hazards may include extreme heat and cold, slippery surfaces, chemicals, stored energy, sharp edges, and biological hazards from the victim or the environment. Since there are an unlimited number of machines, some with very complex mechanisms, it’s all the more important to prepare and preplan for this type of incident. By training and applying some of the basic principles presented here, you can respond with confidence and competence.

PREPLANNING

During building inspections, note the types of machines in your district, their power sources, and their associated hazards. Plan the best place to position fire/rescue and EMS equipment. Find the location of shop manuals, drawings, and hazardous chemicals. If there are special environmental hazards, consider how you will mitigate them (i.e., use of a hazmat response). Determine if there are any equipment/tools on-site that can be used during the rescue. Study and document the cycles of the machines, size-up potential anchor points for rigging. Identify the source of power for the machine and then follow how it is applied. Some fixed facilities have an in-house fire/rescue brigade; if this is the case, participate in its training. Meet with the repair technicians. Their experience coupled with our rescue sensibilities and risk-benefit detachment will add to the efficiency of the rescue response. In-house staff often will make emotional choices; we need to bring a professional, detached attitude that will foster logical choices. You can determine the amount of risk for an occupancy by reviewing the site’s call history. Evaluate new businesses and agricultural/industrial processes in your area, and develop a resource list.


Sometimes, machinery entrapments occur outdoors and far from accessible roads. If faced with this scenario, determine how to transport staff and equipment to remote locations. Add a four-wheel-drive vehicle to agricultural or other off-road responses. Meet with local equipment dealers, and schedule time in their maintenance shops to gain familiarity with machines in the area.


Once some of these basic observations have been made, develop a tools/equipment/resource list for your machine rescue response. Some of these tools may not be typical for fire departments. They may include oxygen/acetylene or exothermic torches, high-pressure air bags, pneumatic ratchet/impact wrenches, small metal-cutting cutoff saws (also known as whizzer saws), lifting jacks, and rigging equipment such as chains/slings and come-alongs. You will also need a well appointed mechanics tool kit that includes standard and metric sockets, a variety of wrenches/pliers, and a “lock out/tag out kit.”


(1) A basic lock out/tag out kit. (Photos by author.)

In many states, the Division of Workers’ Compensation, the Occupational Safety and Health Administration (OSHA), or Labor Department will provide training materials. Salvage yards and other types of recycling and reclamation centers may offer access to surplus machines for training purposes.

RESPONSE

As previously noted, you need various skills when responding to a machinery entrapment. Entanglement within a machine is not routine and may be beyond your training and capability. In some regions, rescue companies, truck companies, urban search and rescue units, and other fire departments have become rescue specialists in machinery entrapment rescue. Add them to your response, and consider including them in your preplans. Consider also other assets such as technical rescue units, EMS, hazardous materials, police (crowd/access control), fire suppression companies, civilian experts, and command staff. After the incident is completed, you may need to participate in reconstructing the accident and the investigation. A well-planned response will not only aid the victim but will also contribute to the area’s economic production and worker safety in general.

SCENE ACTIONS

Command Officer

  • Establish command, gather information, assign assets, set up zones, and restrict access. Hot, warm, cold (staging). The Hot Zone is the area immediately around the machine. Keep unneeded personnel and equipment out of the area. Warm Zone refers to the area where tools and rescuers are staged and that will serve as a decontamination corridor if one is needed. Set up an identifiable command post in the Cold Zone. Establish a staging area where outside resources can check in and be updated on the progress of the rescue.
  • Identify hazards, develop a control plan, and designate a safety officer.
  • Determine the victim’s medical status; compare the victim’s survival time vs. the time needed to extricate. Our goal is to extricate, treat, and package the patient for transport to a trauma center within one hour. Meeting this goal is often the difference between life and death. We call this hour the “Golden Hour.”
  • Track progress and constantly reevaluate the progress of the rescue. Is the victim’s condition deteriorating? Do the crews have the proper tools? Is there a more experienced person or even a machine owner’s manual on-site that would help?
  • Determine the degree of entrapment; will on-scene surgical intervention be needed?
  • Compare the number of rescuers on-scene vs. the number needed.
  • Determine the need for any special tools/techniques/resources.
  • Determine the need for civilian expert help.
  • Determine the degree of difficulty and the amount of time/equipment needed to deenergize/stabilize the machine.
  • Make sure the plan is flexible and adaptable.
  • Determine how the patient will be transported after disentanglement.

Find a machine operator or maintenance person; assess his ability/willingness to help. He may not be suited to work close to an injured coworker for a number of reasons, but he still may be able to give guidance on how the machine works.


(2) A pneumatic-powered tool kit.

In many cases, the trapped worker was attempting to clear a blockage, clean the machine, or conduct maintenance when the accident occurred. Obtaining some history of the events leading up to the entrapment may aid in planning the victim’s rescue and care and treatment.

The goals of rescue planning, which should be flexible, should be the following:

  • Limit the effects of the hazards identified.
  • Know that it will take time to form a solution.
  • Cause no further harm to the victim or subject him to needless risks.
  • Have alternate plans ready (Plans B, C, etc.).

First-Due Company

  • Protect the company, the primary priority.
  • Establish scene safety/control.
  • Control access, find operator/maintenance person.
  • Establish access to the victim/machine; determine the power source and if it can be shut down without causing further harm.
  • Consult with EMS.
  • Begin stabilization, cribbing, rigging, and lock out/tag out (see “Lock Out/Tag Out: OSHA Rule #1910.147”).

Some large facilities equip their personnel with wireless “panic” alarms because of limited or reduced staffing. Check the facility and find out if a system like this is in place and, if so, how to access it to reduce search time.


(3) A portable oxygen-acetylene torch.

These powerful machines often cause severe and gruesome injuries. When managing the patient’s injuries, consider that the compression of the tissues may be preventing the victim from bleeding out; ensure that EMS is ready and in place to manage these issues when the victim is freed. The toxins that can build up in compression injuries (crush syndrome) may also need to be pretreated before the victim’s final extrication. Balance applying advanced life support techniques against the time it will take to extricate the victim, and consider how it will complicate the rescue process. Continuously reassure the victim that help has arrived and the rescue is in progress. The victim may provide valuable information about the nature of the entrapment.

MACHINE RESCUE CONSIDERATIONS

  • Wear appropriate personal protective equipment as determined by the hazard survey.
  • Brief the crews on the rescue plan.
  • Monitor the atmosphere and control ignition sources.
  • Keep in mind that moving one part of the machine may cause another part to move.
  • Do not randomly turn push/pull controls on or off.
  • Reversing the machine could cause additional injury; use caution.
  • Use people as an energy source, if needed. Check the gearing to ensure the direction of rotation. Use a well-placed pipe wrench instead of running the machine. You may not be able to tell which way the gears rotate by looking at the machinery. If you try to slightly “jog” the machine by momentarily turning it on, using its normal power source, you are taking a large gamble with the victim. The machine may not stop, or it could rotate the wrong way, increasing the level of entrapment and injury to the victim. By isolating the power source and using the leverage of a wrench, you can, in some circumstances, test the rotation to help with the extrication and limit further harm to the victim in a more controlled and predictable manner.
  • Size up automatic safety systems. Many machines and industrial processes have auxiliary systems such as auto lubrication, cooling, and limit or position switches. These auxiliary systems often have a separate power source and are triggered into operating by detecting movement, temperature, position, or other conditions specific to the machine’s cycle of operation. Our efforts to rescue a trapped victim may inadvertently trigger one of these auxiliary systems, complicating the rescue process.

  • Treat hydraulic fluid as if it were flammable.
  • Automatic startups can be part of the process, so turn off machines if they are running or not.
  • Consider whether the center of gravity can shift.
  • Widen the base of the machine by using cribbing or shoring techniques to prevent any unwanted movement. In most circumstances, you will want to stabilize the machine as a whole in the position found with the exception of the components you may need to remove or displace to free the victim.
  • Consider partial extrication and transporting the patient with part of the machine.
  • Consider the effects of the extrication on the victim.
  • Consider the effects of the rescue on the rescuers.
  • Since mechanical energy is usually transmitted in a rotary motion, stabilize gears, pulleys, shafts, etc. in both directions.
  • Control pneumatic/hydraulic cylinders, which may move in both directions under power. Hydraulic cylinders may extend and retract under power, just like some of our vehicle rescue rams.
  • Periodically reevaluate the progress.

MODES OF OPERATIONS AND TACTICAL CHOICES FOR REMOVING VICTIMS

An offensive operation would involve entering the hot zone and actively extricating the patient. In a defensive approach, you would wait until the scene is safer or until specialized resources arrive.

The following techniques may be used to extricate the victim from the machine, listed in the order of least risk to increased risk for victim and rescuers. As you plan the rescue, avoid trial-and-error problem solving. Approach the incident logically, and keep your plan simple and practical.

This is usually the simplest method; consider it first. Move the victim or move the machine around. Get the victim to relax. Consider using a lubricant on the limb.

  • Disassemble the machine. This method necessitates a more extensive size-up and maybe also special tools and control measures.
    Check to see if there is a duplicate machine on-site to evaluate.
    You may need special hand or power tools to work on the machine.
    Have on-scene someone familiar with the machine.
    Size up potential reactions of the machine and how they will affect the rescuers and victim during the disassembly process.
  • Force the machine. This is usually the action of last resort when other options have failed.

You need a calculated plan and careful implementation. Keep the plan flexible. This method is the least preferred. It is difficult to control the machine’s reaction, and it may create additional hazards. Also, your tools may not be strong enough for some construction/industrial machines; they may be damaged, and precious time may be lost. (Area businesses may help with the purchase of special tools.) Shield the victim from sparks and debris.

DEMOBILIZATION CONSIDERATIONS

  • Consider any decontamination issues concerning personnel and gear.
  • Do not become complacent when getting your tools and equipment out from the machine; hazards are still present.
  • You may need to leave and allow the property owner to complete the disassembly and retrieve equipment.
  • You may need to leave tools/equipment in place for an OSHA investigation.
  • Inspect the tools and equipment as you retrieve them, and place them back into service.
  • Critique the incident, and make corrections as needed.

Many states, counties, and cities require that the state OSHA unit be notified immediately. Sometimes, the local district attorney’s office must be notified when a serious workplace injury occurs. Follow the local or state protocol pertaining to timely notification, and be prepared to preserve evidence after the rescue has been completed.

•••

Begin training for this type of rescue now. Many industrial machines have heavier-gauge metal and more structure supports than an automobile. By preplanning and providing some basic training, your next machine rescue incident will go more smoothly and have a more positive outcome.

Reference

Zickler, Robert [Indianapolis (IN) Fire Department]. Basic Emergency Rescue Technician, 1997.

LOCK OUT/TAG OUT: OSHA RULE #1910.147

Stabilizing Machine Movement, Neutralizing Power Sources

Establish a safe work area by blocking moving parts and turning off energy, usually at a main disconnect, which is identified by a padlock and “Danger Tag.” This may not always work; there may be two or more energy sources.

The primary source of power for most machines usually is an electric motor powering something else, such as an air compressor or a hydraulic pump, or that transfers power through chains, belts, shafts, etc. When operating an electrical switch, turn your face away, stand arm’s-length distance, and wear personal protective equipment (PPE). Have an electrician verify that the switch is off. Sometimes the switch does not power everything down—i.e., elevators have a separate power feed for lighting and ventilation—or the power feed may turn off other systems you may not want off. Read the labels on the machines and switches, and then confirm with employees.

Following the electrical conduit and cables may also help identify the correct switches. Modern electrical code will often require a “STOP” switch near the machine. Typically, this switch stops the control voltage (lower voltage than the power feed used to operate machine accessories) and may not shut off the main power to the machine, but it will prevent the machine from cycling. Parts of the machine may have stored energy because of their weight and position. A flywheel by design may rotate unless secured.

As you find the sources of power for the machine, determine the machine’s “full” cycle, or stroke. Securing components in place may require blocking/wedging or tying back with rigging/come-alongs in two or more directions. Find out the capacity of the machine; the forces it produces may exceed your rigging and blocking. Look around the machine. The equipment to secure the machine for routine cleaning/maintenance may be nearby. Some machines may need to complete a full cycle before they can reach a “zero mechanical state.” Assess any tension on chains, belts, cables, or other flexible means of energy transfer. Never cut any of these items unless you are absolutely sure you can control the reaction and it will not harm rescuers or the victim. Flexible power transfer parts like chains and belts may have what is known as an idler pulley or a gear that keeps tension on them. The idler, when adjusted, may help with slowly releasing the stored energy in the chain or belt. Sometimes you will find a mechanical coupler device between the electric motor and the pump/compressor. Disassembling this connection is another option for isolating energy. Keep in mind that hydraulic and pneumatic lines likely are under pressure. Cutting or loosening them may result in a high-pressure spray and cause an unpredicted movement of the machine.

Some very sophisticated machines have “safe” positions programmed into their operations. Cutting a belt, cable, or power transmission device may trigger a chain of events you do not want. Apply the old hazmat adage “What happens if I do nothing?” Consider that if you turn off the pressure of a hydraulic or pneumatic system, the lines may bleed down, and the machine will move, block, or rig these components in place. These systems will often have pressure accumulators. Look for these tanks and, if possible, bleed off their residual energy, or valve it off. Remember, you are there because something has already gone terribly wrong. Chances are that the person stuck in the machine will have forgotten more about it than you will ever know. It is not uncommon for workers to bypass safety devices. Proceed with caution.

When developing a plan to control energy sources, consider the presence of compressed or extended springs, steam lines, and backup battery/generator power. If possible, verify a “zero mechanical state.”

To “lock out/tag out” means to prevent accidental startup and reenergizing of the machine. Verification is a vital part of any workplace lock out/tag out program, but it may not be possible during a rescue. Consider the risk to the trapped victim in attempting to reenergize the machine, which is the easiest and most common method of verification of lock out/ tag out, and verifying a zero energy state for fear that the proper switches/valves are not in the off position. Size up all possibilities: potential energy by virtue of position and weight; compression of air/fluids; tension of belts, cables, and chains; kinetic energy; chemical reactions; and any observed motion. Consider the possibility of a “timed” cycle for the machine. Timers may reach their action point after you start working and engage in something you are not counting on. If the proper locks and guards are not available, post a police officer to prevent accidental tampering during your operation.

“Blocking and bleeding” is another lock out/tag out technique. It is complicated and could potentially make the overall problem worse if done improperly. Blocking involves blocking a carrier of product, usually a pipe, upstream of the incident. Bleeding involves removing the product from the isolated section of pipe. The “blanks” (plug inserted in a flange to seal off the pipe) may leak or a spill/release may occur when draining the pipe of the product. Qualified technicians, under the supervision of the fire department, should perform these actions if they are needed to ensure that they help the rescue effort. Indiscriminately operating valves and switches is dangerous. Review drawings, and consult with someone who knows the system. Turning the machine off may cause it to relax or cycle into a neutral position, causing more trauma to the victim.

When stabilizing the machine. Consider the following:

  • Estimate the center of gravity; can it shift if the machine cycles?
  • Determine the base of support. Is it muddy, sloped ground, or an oily floor?
  • Estimate the weight/force of the machine, and compare it with the capacity of your cribbing and rigging.

STEVE SHUPERT is a 17-year veteran of and a lieutenant in the Miami Township Fire Department in Montgomery County, Ohio. He is assigned to the second platoon, Engine/Rescue Company #48. He is a rescue squad officer with OH-TF1 and serves on the DHS/USAR Rescue Working Group.

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