Direction of Force: Working Safely Now and at TEOTWAWKI, by Arizona Slim

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We all accept basic firearms safety rules and know that if we were able to carry them out flawlessly, there would be no such thing as an unintended injury or what we pitifully refer to as an “accidental” discharge. [JWR Adds: Properly, this is termed a Negligent Discharge.] There is another much more broad concept that, if we can also just hone it to a fine edge, we can employ it across a broad array of activities to greatly reduce the chance of damage, injuries and even death. Activities as diverse as cutting a project out of construction paper, opening that latest package from your favorite prep supplier, chiseling a door for new lockwork, raising a grain silo, stretching a fence or winching a truck out of the mud.

Like the safety rules for firearms, you can stay safe to an amazing degree, if only you can maintain the awareness and follow-through. Avoiding injury is always important of course, but in a TEOTWAWKI situation the need to avoid even minor injury will be of supreme importance, and more serious injuries might be more likely to result directly or indirectly in loss of life for lack of definitive medical care, or the inability to perform in vital roles and activities.

Stated briefly it entails always being aware of the Direction or Line of Force. Anytime work is being done, force is there to make it happen. From the tiny force necessary for something as trivial as cutting the string off a bundle to the amazing strength of a tractor pulling a disc harrow across a field, to a crane lifting a tower for a new windmill. From big to small, anytime any amount of force is applied energy is amassed that can be released unexpectedly, sometimes with catastrophic consequences. And “force” is everywhere around us, doing jobs large and small, making things happen or keeping things in check, all the time. Most times is obvious because work is getting done, something is moving! Other times it’s more passive, such as the stored energy created by  tension of guy wires supporting a radio tower against gravity.

Force in any direction: pulling, pushing, lowering, lifting, bracing, supporting, levering, prying, twisting. Whether you are using your body, a rope, wire, cable or wire rope, chain, a lever or tool of any kind, a brace or prop or other structure. When you are applying force to accomplish some task, applying pressure or attempting to resist or overcome other forces, like gravity or tension, there are points of failure in the “system,” or in the “machine” that you cannot entirely control or predict. What you CAN do, is make sure you are not in the path if the stored energy is suddenly released, or have a plan to accommodate the movement. And you can stay safe.

In the paragraph above I started to write “the unexpected movement” but that’s rule number one for what we’re going to try to accomplish, making sure it’s ALWAYS expected! When it comes to staying safe when force is in the picture, you must try to banish “unexpected” from your vocabulary.

You are lifting an engine with a block and tackle, the direction of force is a vertical lift against gravity. If the hoist fails, if the chain fails, if the attachment point fails, the release of stored energy, the mass of the engine, will be straight down. Make sure no body parts are ever in this path and no failure will harm you.

If you are raising a radio mast, or a windmill or a light pole, you know that failure will cause the object to fall out across the ground, and until it is almost vertical the path is easy to predict. But don’t forget about the other pieces of the system. What about the cable or rope that is applying the force? Which direction will it recoil if the pressure is suddenly released? Are there other pieces? A block and tackle, a winch, a come-along, supports, a tractor or other vehicle? What paths might these pieces describe if suddenly set free?

And in preparing to sidestep – literally – one of the greatest killers, is there anything in the vicinity that might change the path of a falling or suddenly released object? A great many serious injuries occur when a suddenly released moving object encounters an obstacle and deflects in an “unexpected” direction. (There’s that “u” word again.) You may think you are prepared for something to fall down. Provided it does in fact just fall “down.” But have you considered whether anything in the area could re-direct the object sideways? That takes being or getting out of the path from straightforward to perhaps impossible.

You are using a winch to get a truck out of a mud hole. The direction of force is along the winch cable in the direction of the pull. If any part of the system fails, things are going to move along this line. Either vehicle may shift, but the most violent reaction will be in the cable itself, being much lighter than the vehicles. It will recoil along the direction of the pull and can sever limbs as it whips around. If you’ve ever seen a winching and seen a tarp draped over the cable and wondered what the purpose was, it’s to hopefully capture and dampen some of that energy if the cable or an attachment point fails. You’ll also see hoods raised to protect windshields. But the best answer is don’t put yourself along that path of force. That’s one reason the winch controls are typically on a long lead.

A drawback to the ever-handy come-along discussed here recently, is requiring that you be up close to operate it. Another reason to never approach the rated limits of the device or other parts of the system, and to replace any components that show signs of wear or corrosion. You might employ the canvas drape device also if spacing permits.

Expand your awareness of direction of force to also encompass anything that is under tension. It’s easy to overlook things that are not currently being employed to apply force to move something. There are plenty of things that seem “passive” but are constantly under tension, that have the stored energy of a force being applied against a restraint, that can create a severe consequence if a part of the system fails. The guy wire on a tower or pole or antenna mast. A new fence line that hasn’t relaxed. A temporary or permanent prop or brace against an object or structure. These are all resisting tension or applying pressure against the force of gravity. It isn’t usually difficult to understand which direction things are going to move in a failure, but you have to expect the possibility of a failure and have a plan to be out of the way, and you have to account for all of the various pieces of the structure or machine that may be involved.

I first read a paper on this subject around the time I learned to sail. If you’ve ever been on a sailboat you know that it’s a jumbled (incomprehensible to the uninitiated) mass of cables and ropes comprising standing and running rigging. Cables that keep the mast and other things where they belong, and ropes keeping sails in place and moving them about as required. The forces involved are unimaginable. The pieces are carefully engineered, but not overly so on most pleasure craft. You look at the diameter of the cables and ropes, you look at the stainless fittings, you look at the fasteners, you think about the wood and Fiberglas bits they are connected to, and you wonder how on earth any of it stays together against the enormous pressures involved. But what really occupied my time was deciding where I did not want to be if any part of the machine failed. And though it’s not easy to escape the myriad paths of potential failure on a sailboat, I was always aware and tried to minimize the risk by not putting body parts close to and along the axis of lines under strain, or anything they controlled the position of for any longer than necessary.

When you are using a chainsaw, of course you have taken precautions against the dreaded evil kickback, but do you keep in mind the amount of pressure you are applying and where that pressure will direct the saw if the limb you’re cutting suddenly snaps or the cut breaks through? How and where you might fall if it throws you off balance, and more importantly what happens to the running saw?

You are using a digging bar to pry out a buried rock, do you maintain your awareness of what’s going to happen when the tip slips? Of what’s behind you if you fall? Or how you will control the dangerous top end of the bar if you do? I have shifted my position to one that didn’t give me quite as much leverage, but gave me a much better chance to control myself and the bar. That’s the trade-off you have to see as invaluable. The job will get done, eventually and with sufficient effort. But you may only get one chance to avoid a serious injury.

Stretching a fence is always dangerous because being up close and personal is unavoidable. Working deliberately, with another pair of hands, wearing appropriate heavy duty clothing and safety gear, minding the condition of tools, using a back-up tensioner, deploying canvas drapes a la winching, staying as close to the tensioner as possible while starting to attach the wire, working with your back to the tensioner, and working on the opposite side of the posts from the wire all help if something lets loose. Not to mention being aware of the energy stored in a new coil of wire when releasing the strapping.

When you are applying a great deal of force to a drill, do you keep in mind where that force is going to go if the bit breaks, or breaks through the material? Have you ever supported a panel from behind while pushing a drill through from the front and had the bit break through more easily than expected, only then to consider the juxtaposition of your supporting hand and the bit’s path? Your secret’s safe with me, comrade.

When you lift something with a jack, do you consider what will happen if the jack slips or fails? Yes, but what if jack stands won’t work in this instance? What if it’s a hi-lift jack situation? And have you considered a sideways shift of the object lifted as opposed to a simple straight fall? Lifting something, whether by pulling from above or pushing from underneath, always creates potential energy against the pull of gravity. And there is always potential for the support to fail. Don’t let a body part you value be there when it does.

All of this is not just about the “heavy-lifting” labor around the homestead. When you are cutting something with a knife or scissors, do you consider where the force, and the momentum that will suddenly occur, will carry the blade if the material gives way or the blade slips out of the cut? Another of your body parts, someone else’s, or just an object or material you don’t want to damage. How about when using a wood chisel? What about a hammer and cold chisel? A crowbar or pry-bar?

My son is eleven and can open any box or package or other wise wield a utility or pocket knife or scissors or shears more safely than many adults I know. Why? Because every single time he’s ever made such an effort I have been right there with the same question: If the blade slips out of the cut, or the material gives way, where is the blade going to go? Where is it going to end up? Where is it going to stop? And those things have occurred often enough – as they always will – to nicely demonstrate the concept and drive the point home.

When you have a stubborn fastener and you are applying ever-increasing amounts of force to a wrench, do you keep in mind the direction and force of movement if the wrench slips off or the tool or the fastener breaks?

Some of these scenarios we’re all familiar with and know the outcome is likely to be nothing more than some painfully skinned knuckles. But if you train yourself to always recognize and be aware of force applied, you can stay safe when the machine and the project and the forces ramp up to levels where a failure can cause serious injury or death. Or even just serious damage to the object in question and other things around it. Every single time you apply pressure – force – to anything large or small, realize that force is necessary because something is resisting movement. Take a moment to consider what will happen and how things will move if that resistance is suddenly lessened or removed, for any reason.

If you are making a cut with a circular saw you must be aware of the direction of force in the event of a kickback. But you must also be aware of the direction of force you are applying to move the saw through the material. Where the saw is going to go if the blade rides forward, up and out of the cut. What is beyond the material you intend to cut? And the big common target in these instances – where is your other hand? And if that happens, is it going to throw you off balance with a running saw in your hand? What happens when you can’t release the trigger because of your grip and because you’re trying to manage a fall? Where is your other hand going to end up as you try to break the fall? Under a running saw perhaps? Always consider the direction force is being applied and what the consequences will be in a failure of the system. I have stopped mid-cut and adjusted my stance and my grip to improve my balance and position, and to increase my control of the saw – including being better able to consciously release the trigger – in the event of a sudden change. All because this awareness is something I’ve cultivated and nurtured until it is ever-present.

You’ve heard that a sharp knife is safer than a dull one. This may seem counterintuitive, but managing force is exactly what this axiom is talking about. Sharp knives, sharp chisels, sharp saw blades all require much less pressure, much less force to cut through the material at hand. Much less pressure being applied means much less potential movement to avoid or control when material gives way or a blade slips out.

Stored, potential or “passive” energy can be difficult to see sometimes. A friend put up a ladder against a thick limb that needed to come down. (The standard rule is don’t use chainsaws on ladders, but we know that only works in the mystical world where the manufacturer writes the safety manual.) He had experience with a chainsaw and took all of the standard safety precautions. The cut was just outboard of the ladder, he wouldn’t have to reach, and the limb would fall cleanly in an open area away from the ladder on a slight away slope so it wouldn’t roll back. Even though he was actually not far off the ground, he even tied a short hank of rope over the top rung and the limb, just so he could concentrate on the cut. Sounds pretty thorough, so what was he missing?  The force buried in the tree. The effect of gravity on the tree from the large limb he was about to remove. It was as though an invisible rope was bending that tree toward the ground, and that rope was about to be cut. Disconnected from all of that extra weight the entire tree stood up straight in relief and flung him and the ladder backwards. He was very lucky. He did not suffer any injury from the fall, and was able to consciously toss the saw away. Great lesson. If only there was video.

Any time you lift something, beware of the direction of force of gravity. Anytime you push or pull on something beware of the direction force is being applied and what is going to happen to you or the objects involved if something fails. Anytime you see anything under tension or pressure, keep in mind the direction of force involved and avoid being in the path, or have a plan to remove yourself from the path. In many cases the movement will lie in two directions, the direction of the force and the “rebound” direction opposite, but always along the same straight line. That’s the axis you need be keep in mind.

At the very least perhaps you can avoid being the latest viral internet video with “fail” in the title. But you might also save a body part or life itself.

A simply mantra can reduce your chances of injury by many orders of magnitude:

  1. Always consider the direction of any force(s) being applied or potential energy existing in everything you come in contact with.
  1. Always expect some part of the system or machine to fail.
  1. Don’t be in the path of the direction of force, or any objects that may move in the event of a failure.
  1. If you are physically a part of the “machine” be prepared to protect yourself by maintaining our balance and position. Or in the case of some large complex operation, have a plan to immediately distance yourself in the event of a failure.

Stay safe!

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