EXTRICATIONS FROM POWER TAKE-OFF SHAFTS
RESCUE COMPANY
Power take-off shafts (PTOs) are common on a variety of agricultural and industrial implements. The most familiar location for a PTO is the area where the implement is attached to the farm tractor. The PTO tansfers the power of the tractor into the implement being driven. A very high degree of torque is needed to power most equipment, and therefore the speed of the shaft is generally great (540 to 1,000 rpm).
When an implement leaves the factory, shields that protect the user from contact with the revolving shaft are in place. The shields are designed to fit over the shaft so that when someone brushes against it, steps on it, or reaches over it, no body parts or clothing will become caught in the revolving shaft.
Like a shield on any piece of equipment, this one is not easy to work around. An owner/operator often will remove it in order to perform maintenance or repairs on the shaft itself. In addition, since it may be expensive to repair a damaged shield, an owner/ operator may believe it is more costeffective to simply remove it and operate the equipment without the shield.
liven though the Occupational Safety and Health Administration (OSHA) does not regulate small family farms, this doesn’t mean safety may be compromised. Operating the PTO shaft without its shield so increases the risk involved that manufacturers often make sure they place prominent warnings on these pieces of machinery. Some even require that buyers sign a statement absolving the manufacturer/seller of liability in the case of an accident. Despite these stark w arnings, operators still remove the shields.
(Photos by author.)
PTOs generally are constructed of a very heavy gauge steel because of the degree of strength needed for the force exerted during operation. They may be solid square, octagonal, or round shafts surrounded by tubular construction of the same design. The shaft is attached to the tractor with a sleeve-like device that fits over the solid round shaft, referred to as a spline. On older models, the pin that locks the two together is another location where modifications may have been made. If the pin was damaged, it may have been removed and replaced with nails, screws, or bolts that fit into the opening. All of these modifiers will do the job of the factory-installed pin. However, they also will create potential hazards, as they often provide more of an exposure to the operator. (On the more modern implements, the hazard of the exposed pin has been eliminated; the newer collars are smooth, and no pin is exposed.) Another potentially problematic area is a knuckle-type coupling where a union, which may resemble a universal joint, joins another shaft that goes into the machinery being driven. The configuration of this joint is such that fingers and clothing can become caught in the large openings during operation.
PTO injuries are not restricted to any one part of the anatomy. However, as is the case with the majority of farm-related accidents, hands and arms most often become involved. Clothing that becomes caught will involve whatever body area it is covering. A person’s ability to escape often depends on the strength of the clothing. Multiple layers make escape most difficult. The majority of these incidents occur during harvest, in the latter portion of the year and during the later hours of the day —as you might guess, when dress is in layers because of the cold.
EXTRICATION CHALLENGES
Rescue personnel often find the equipment running when they arrive. Among the reasons for this is that, once entrapped, operators often are not able to reach the clutch mechanism that disengages the PTO or any switch that disengages power. Those who respond to help may be unfamiliar with the power equipment and unable to shut off the pow’er. If it hasn’t been done already, rescue personnel will be required to turn off the power, which in itself can be a problem, as each type of implement has a different method for disengagement. If the victim is conscious, he/she may be able to instruct you on the procedure for shutdown. Do not depend on this. One solution is to train personnel in the safe methods of turning off equipment. This needs to be doneprior to an incident, perhaps with the aid of implement-repair personnel during a monthly training session.
Disentanglement may be as simple as cutting through the clothing holding the operator in place. Utility knives, paramedic scissors, and scalpels all may be used. Often cloth becomes wrapped so tightly that scissors alone are not able to free the victim. Extrication of a limb or other body part often will require cutting or separating the shaft from the patient. Once again, remember the strength of the material with which you are dealing. Many hydraulic shears are not designed to handle steel of this strength; even if they are, the motion resulting from your activities may be more than you want the victim to experience. Many of these shears won’t even fit into the space involved. Your resource list of equipment should include portable band saws and/or reciprocating saws (along with extra blades). A good hacksaw is useful if you can keep movement to a minimum. Use lubricants with the saws to reduce heat and aid the saw through the metal. You can use cutting torches if heat transfer can be kept to an absolute minimum. Remember, agricultural accidents require multisystem responses; onscene fire protection is a must. Disassembly of implements (nuts and bolts) is another option that may be available to you. A good set of mechanics’ tools is required for this.
PREVENTION
Treat farm machinery incidents as you would fire: Prevention is as important as response. In my region, the Wisconsin Farm Bureau sponsors a first-aid training program for farmers. But even without state support, your department might consider working with farmers for mutual lessons learned. Some things to consider are the following:
- Emergency personnel should be
- familiar with the agricultural settings in which they work and with the specific machines common to their regions.
- Farmers can provide information about specific machines, particularly old equipment In some cases, though, implement dealers are the best source of information.
- Hands-on experience is a must. You may be surprised at what you learn. These machines are tough, and your tools may not be tough enough to do the job. Also realize that the majority of equipment will be in bad repair due to age, making forcible means of extrication your only option.
- All parties involved need to understand how fast a PTO shaft incident can happen. Most accidents happen at the end of the day, when people are tired and may be rushing to get a job done. A PTO shaft can entangle a third of your arm in less than one-third of a second.
EMERGENCY MEDICAL TREATMENT
Emergency medical care will be dictated by the nature of the patient’s involvement. Extremities most often are injured. Angulated fractures, whether open or closed, present rescuers with splinting challenges once extrication is completed. Patients who have attempted to escape and consequently have entrapped the remainder of their torsos in the process will have multisystem trauma. Head and neck trauma occur when the upper body is wrapped onto the shaft and the head strikes the ground, hitch, or implement fenders. There also may be strangulation-type injuries when scarves or other articles of clothing near the head anti neck become caught in the spinning PTC). Individuals who decide to step over the operating PIC) also may incur genitalia injuries (these may not be immediately life-threatening; however, the degree of pain and emotional injury is great). Management of shock should be an early consideration. Supplemental oxygen, a pneumatic antishock garment, IV administration, and control of external bleeding are all areas that will require your attention. Give early notification to your area hospital emergency room so the appropriate staff can be available and prepare for your arrival. On-scene record keeping is very difficult due to the volume of activity; therefore, a useful means of immediate documentation is an instant camera. Photos of the entrapment and extrication can provide a wealth of information to the receiving emergency room.
All agricultural accidents, especially those involving PTC) shafts, can be very demanding on emergency responders. In any emergency situation, be sure to follow local protocol and guidelines. Preplanning and training will help your department successfully manage this type of incident.
