I've been very interested in the physics of rescue and extrication for a long time. Early in my career, the tools for rescue were very limited. There were Hurst spreaders with the add-on cutters, natural fiber ropes with a limited supply of those newfangled dynamic kernmantle nylon climbing ropes, and non-locking carabiners. Virtually every other rescue tool we had was adapted from the construction, wrecker, or auto-body-repair industry.
The limitations on tools and techniques made for some long and frustrating rescue attempts. Some of them were successful, some not-so-successful.
The tool limitations forced us to create techniques - sometimes on the fly.
That led to some very dangerous and ineffective things being tried because we couldn't think of anything else under the pressure of trying to save a life.
After a few of these frustrating episodes, I sat down with a very brainy guy from my rescue company and said "Steve, we've got to figure out a basic set of rules to make our techniques faster, safer, and more effective." He just looked at me with glazed eyes and said "We all know that you dream about Hurst tools and rope when you sleep at night, you're on your own." I mulled it over and eventually had a "Eureka" moment. I call the concept the Rule of Opposites.
The Rule of Opposites is simple; "If what you're doing isn't working, do the opposite."
The Rule of Opposites has some corollaries;
1) If you can't pull, push. We used to pull a lot of steering columns with chains and either spreaders and come-alongs. Then crumple zones came along, and we figured out that was often a better technique to push the dashboard with rams.
2) If you can't lift, dig. Heavy lifting is not always possible, especially when the object is very unstable. You may be able to dig the victim out without risking the unstable object toppling, especially if heavy lift capability is not quickly available.
3) If you can't lower, raise. If you are working a vertical rescue on a 500-foot elevation and you only have 300 feet of rope, you won't be able to lower the patient to the ground. It takes more work, but you can simply complete the pickoff and raise the patient to the top, then use the trail, road, elevator, or helicopter to complete the patient evacution.
4) If you can't cut, dissasemble. I realize that this is not, strictly speaking, an opposite, but it's the rule of thumb for heavy machinery extrication. Industrial and farm machinery is made to last, and it is often tougher than our hydraulic cutters, saws, and even cutting torches. A simple ratchet set and a can of WD-40 can make an otherwise difficult extrication into a literal "nuts and bolts" exercise.
5) If one simple machine won't work, try another simple machine.
If an lever isn't working, try an inclined plane. If you are trying to lift a heavy object and can't get enough leverage, try driving cribbing wedges under the edges of the objects. It's amazing what a few wedges can lift.
6) When terminating, reverse the rescue. Stabilizing rescue and extrication scenes can be very complicated. If you're going to remove shoring from a trench or cribbing from a wrecked vehicle, it's usually a good idea to take the shoring/cribbing down in the reverse order that you built it. If you shore trench panels in the "middle-top-bottom" sequence, then the shores should be removed in the reverse order; "bottom, top, middle". We need to be just as careful about using the Rule of Opposites for rescue termination as we do when extricating the patient. Corollary #6 is also used when bedding aerial ladders. We unbed the ladder after stabilizing the truck in order to rescue or flow the ladder pipe, so we should bed the ladder prior to retracting the stabilizers. Ditto for lateral stabilization. The IFSTA aerial operations manual calls for stabilizing the uphill side first, then jacking the downhill side so that the truck is within 5 degrees or so of level. This keeps the uphill side from forcing the low side down and risking tipping the truck or overextending a stabilizer. When retracting the stabilizers, we should store the downhill side first in order to follow the Rule of Opposites.
The most important corollary is 7) If something isn't safe, make it safe. We deal with inherently dangerous situations every day. We can't control how unsafe the original incident is, but we can make it as safe as possible by wearing appropriate PPE, completing good size-up, developing and following a sensible Incident Action Plan, using Safety Officers, establishing collapse zones, demanding 100% personnel accountability, stamping out freelancing, wearing our seat belts, and staying out of Born Losers.
I'm sure that there are more of these out there. I'd be interested in hearing your ideas. Oh, and now I'll follow Corollary 8) When you want to learn, don't talk.
I updated this to include one point that I forgot in the initial post:
Corollary 9) Reverse the entrapment mechanism.
An example is the dash roll technique in frontal vehicle collisions. In most cases, the entrapment mechanism for the driver and front-seat passengers is that the dashboard and steering wheel/column get forced down and in on the patients. In this case, the Rule of Opposites calls for using our tools to move the dashboard up and out - the opposite of the entrapment mechanism. The same goes for structural components collapsed onto a patient - we use air bags, cribbing and pry bars, or bolting and a crane to reverse the mechanism.
Thanks everyone,
Ben