Introduction: Yesterday, I got embroiled in a discussion of workshop safety. Unfortunately my comments appeared to be directed at an individual, which was not my intent at all, but which got in the way. For some reason, I care passionately about this subject and I wanted to get my thoughts out in public without incidentally insulting anybody. So, I decided to write the following. It is a shortened version of Chapter 13 in my book, Notes and Reflections on Shaving Wood
Epigraph: “There are a lot of lucky people in the world but it sure is hard to predict who they will be.” B. Benjamin
This quotation puts great wisdom in a simple sentence. All custom woodworkers are playing roulette with their fingers and other body parts, and many have lost at least one spin of the wheel. Fortunately, the odds are more in your favor than in a casino. The risk of injury, even from unsafe behavior, is low. This is a good thing and a bad thing. The good part is obvious: most people have long periods where nothing bad happens. The bad part is that runs of good luck can reinforce unsafe behavior. Some people decide that certain safety practices are unnecessary, because they get away with unsafe practices (or see others get away with them).
A common attitude is: “I’m always in control so I don’t need safety practices.” They may decide that certain safety equipment is not really necessary, that they are too lucky, too careful or too smart to be injured. An example is someone who says that he is always in control, “always knows where his hands are,” so to speak. For short, call this a cowboy attitude. That used to be me, until I injured myself because of my ignorance and cowboy attitude.
Worse, they may preach those unsafe practices to others who, unfortunately, may believe them. (They may be very quiet after their number comes up and they see the error of their previous cowboy attitude.) Novices should not be mislead by people who espouse this “cowboy” workshop philosophy. They are whistling past the graveyard. It is not their technique that is exceptional – it is their experience that is exceptional.
In the last decade of my academic career I studied patient injuries. I learned something about errors and accidents. Accidents are predictable, although unexpected. Accidents happen when rare, uncontrolled, events coincide, when people, equipment and procedures fail at the same time.
A woodworker is seldom, if ever, completely in control. There is always a residual amount of variation that we can’t or don’t understand. Wood is not a homogeneous material. Neither is steel There are knots, grain variations, surface imperfections, foreign body inclusions. . A saw blade is a steel alloy, usually with carbide sintered on the teeth. Variation in manufacturing is always a possibility. A tooth can come loose without warning. A bit of oil or rust on a shaft can let a router bit come loose from the collet. A tool, saw, router, etc. may slip out of adjustment. We, the operators, have lapses of attention, etc. So there is always some unexpected moment when the workpiece rocks on a speck of debris, the cut closes on the blade, the cat runs between your legs, the lights flicker, whatever, and your attention is diverted.
Safe practices are effective when (if) they increase control. The paradox of a cowboy attitude is that by claiming to always be in control the cowboy woodworker is actually opting for less control than he/she could have had.
Workshop safety requires specific procedures for specific operations, carried out within a general framework or strategy. A strategy of safety reduces the risk of accident by (1) excluding unsafe conditions and (2) adding layers of protection, so if one layer fails there is another to save you. You won't be injured except in the very unlikely event that all of them fail at the same time. That’s why I use the “roulette” metaphor. Injury remains possible, but the odds against it can be greatly improved. The operator can decide how safe he wants to be.
The tactics of safety involve methods of operation. These are often misunderstood because of the way that manufacturers usually present them – as “don’ts”. Furthermore, many of these “don’ts” are so obvious as to be insulting. "Don’t touch the spinning saw blade." Most people stop reading about then. Nobody goes into his or her shop not to do something. We go into the shop to accomplish a series of operations that lead to a goal.
We should not separate safety from effectiveness. When we try to separate them, they can become antagonistic opposites, and we think that we have to balance safety against productivity. Most people who are injured chose to carry out an unsafe operation. The reason? They wanted to accomplish something and did not know how to do it safely. But they did it anyway, unsafely. The tactics that I am talking about are how to accomplish a task as safely as possible: choosing the right tool and using it correctly.
For example, suppose you want to cut a molding strip with a power router and a table saw. You have a choice: cut the profile with the router on the stock piece and then cut off the narrow strip, or cut the narrow strip and then cut the profile with the router. Same result. The first method is obviously a safer procedure. (You probably already knew this – its just an example.) If the narrow strip has already been cut off the stock piece, don’t use a power router at all. Use a hand plane.
Hazardous conditions include obstructions on the floor like lumber, extension cords, sawdust on a glazed concrete garage floor; dim or glaring lighting; measuring tools left on the saw table; and animals, kids or gabby adults in or near the shop. Most of these can be excluded easily from the shop, except maybe the last one. Your general mental state can also be a hazard, e.g., working while angry, tired, rushed, or distracted; and working in too tight a space for you and the task at hand.
Avoiding unsafe conditions is a form of hygiene. Like eating well, quitting smoking, etc., it can feel like a real pain, at first, and may feel strange. You may ask why you are bothering, when you don’t have the problem that your good hygiene is preventing. (Another paradox.)
Individual hazards can interact. Suppose that you have a 1% chance of injury from tripping or stumbling while operating a power tool; a 1% chance of being injured because of poor lighting, and a 1% chance of injury while being distracted. If they didn’t interact, these risks could add up to something like a 3% chance of injury. This is bad enough. But if they do interact, the risks may be higher – in fact they may go instantly to almost 100% , where only luck can save you.
The second part of a strategy of safety is to add layers of protection. This basic idea is the complement of hygiene – it is about safety equipment and appliances you add to the workplace to make it safer, such as guards, push sticks, jigs, protective eye wear, dust collectors, and such.
This involves proper technique, but you need to have the right equipment in place in order to practice proper technique. So, this is about more than keeping guards in place. For a simple example, some rip cuts on a table saw should be made with fingerboards to hold the work against the rip fence, and a long push shoe that holds the work down as it guides it through the cut. If you don’t have or don’t bother to find a fingerboard and push shoe, you can’t practice proper technique.
Most people will just go ahead and make the cut with a push stick or their fingers, which is why this aspect of strategy deserves attention in itself. It is not hard to keep the proper instruments within reach of each tool, but you have to decide to do that.
Safe and effective woodworking technique within a strategy is very powerful, as the following example will show. Suppose you always try to rip on a table saw using correct technique. Suppose you manage actually to do this 99.9% of the time. (That would actually be more consistency than most of us could actually achieve.) So you would have a 0.1% chance of a serious kickback, assuming everything else stays the same. That’s 1 kickback in 1000 cuts over the long run. You are likely to have a serious kickback eventually if you use your saw a lot, you just don't know when – it could be your next cut.
Now suppose just having a a riving knife installed, or a splitter and anti-kickback pawls, also prevent 99.9% of serious kickbacks. If you use both good technique and have a splitter installed, your chance of kickback drops to 1 in a million. Maybe you will never have a kickback. If you add a well-designed push shoe to hold the work down, then maybe the chance of a kickback would be 1 in a hundred million, and so forth. These odds improve geometrically because each layer of protection has to fail simultaneously or in sequence before the kickback can occur. The laws of probability give us the leverage we need to be safe. This advantage is literally too good to pass up.
Finally, the foundation of safe practice is to decide that competence and safety are two sides of the same coin. Both require knowledge, skill and the right attitude. One side of competence, what we usually mean by the term, leads to quality. The other side leads to safety. They are inseparable aspects of the same issue. Cowboys adopt a tough “git ‘er done” facade, but the fact is when you are out of commission because of an injury you will not be getting much done (or making much pay, either).
We can develop safe habits, get used to them and not want to go back to the old ways. We can quiet the voice that says, “Hurry up.” and amplify the voice that says, “That’s not how you do that.” “Don’t ever put your hands there.” “Put the guard back on.”
So, safety hygiene, layers of protection, choice of tool, and proper technique. It is not that hard. Perhaps many accidents would be prevented if more woodworkers took as much pride in safe practices as they do in cool tools.
Be safe
Doug Hepler
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Originally Posted by Simon MacGowen
