Friday, September 26, 2014
Is It Really "For Your Own Good"?
Just last week, someone asked me why I wanted to get rid of the mandatory helmet law in Washington State. Here's why; I feel that every motorcyclist has the right to choose the level of risk they wish to accept, based on their own experience and knowledge. As the ones actually using the helmets, we should have the choice whether we consider the risks of wearing a helmet acceptable or not. Don't be quick to say there aren't risks to wearing a helmet, there are. Let me explain what I mean.
In an impact, let's say your bike comes to a sudden and abrupt stop. Newtons First Law states: " An object in motion tends to stay in motion, unless an external force is applied." The bike stops, you're going to keep moving. If the head and helmet don't strike anything, the G forces being exerted will force your head to continue in the direction you were traveling. This continued motion creates great stress on the neck. That additional three pounds of weight on your head, when the G forces are added, can easily become thirty pounds or more. The musculature and ligaments can be torn, and vertebrae can be broken by the sudden and intense forces being exerted. Helmet manufacturers are aware of this, and some even admit it, such as Racers Market. One of their executives made this statement in an email; "The speed of impact if the helmet actually hits something is important. Likewise, the speed of impact with a heavy helmet when you don't hit something with your head is important; as the heavier helmet stretches your neck more, with a risk of neck injuries."
We have all experienced this effect. Ever stepped on the brake and felt yourself move forward? That is the inertia of your body continuing to move forward even thought the vehicle you're in has slowed. The harder you hit the brakes, the more severe the effect it. The same thing is happening inside you as well. When your head suddenly stops moving because it has impacted an object, your brain, and all the tissue inside continue to move. Those moving organs and tissue move until they are forced to stop moving by an external force (like your skull) slamming into it and rebounding back as the organs and tissue decompress. All this moving and rebounding can cause damage. In a wide range from minor to severe. Even without fracturing your skull. Wearing a helmet, does not stop this internal movement. It may diminish the movement caused by a glancing blow, but a direct impact will still have the same results. Since Newton's First Law is inviolate to the best of our knowledge at this time.
All this comes down to impact speed. The higher the speed of impact, the more damage can be done due to inertia and internal motion. Even without fracturing the skull, the brain and connective tissues can be severely damaged due to this process. Some helmets have been shown to have a direct correlation to higher rate of fatal brain damage and skull fractures. A study by Drs. Cooter and David from the Australian Craniofacial Unit at the Royal Adelaide Hospital shows that full face helmets with rigid face guards; while protecting from facial fractures, tend to have a higher rate of basal skull fracturing, and fatal brainstem damage than other helmets. Even open face helmets had a significantly lower rate of brain damage, although facial fracturing was quite a bit more severe and traumatic. It is beleived that the fracturing of the face actually helps to disperse the forces impacting the head, allowing for much lower levels of inertial motion and corresponding damage to the brain and other soft tissues. Follow the link to see the study results for yourself. Cooter Study
As you can see, wearing a helmet carries with it no real assurance of surviving an impact to the head. The inertial effects of the head and helmet not impacting anything during a crash, can be quite catastrophic as well. Visualize if you will, your body impacting the side of a car at 25 mph. Your shoulders are at the roof line of the car, and nothing is there for your head to strike. Since the car is solid, your body comes to a sudden and jarring stop. The orgasns and tissues inside continue to move until restricted by other orgasns and tissues inside. But with nothing to stop its inertial motion, your head continues its sideways motion. The G Forces adding weight to your head and helmet, making them feel several times heavier. The force of that weight stretching and straining muscles and tissue, and the extra weight of the helmet only exascerbates the issue. Neck injuries, sometimes quite traumatic ones can result from just this sort of impact. This can result in a 'hyperflexion' of the neck, and even cervical fractures.
NHTSA proudly proclaims that helmets are only "estimated to be 37% effective". So basically, helmets are effective in just over 1 out of every 3 crashes. Does that mean that NHTSA knows that nearly the inverse ratio of fatal accidents are attributal alcohol and excess speed? With the higher impact speeds involved there is little a motorcycle helmet can do to prevent trauma. The sheer magnitude of the G Forces involved creating such intense inertial pressures within the skull. Even if the helmet does work sufficiently enough to prevent a skull fracture, the physics of motion show that the brain and its corresponding tissues will receive excessive damage.
At low speeds, and with glancing blows, helmets seem to be quite effective. But as impact speeds rise above about 13 mph, there is "a statistically significant effect which increases the severity of neck injuries". As shown in the Goldstein Study.
Those are just a few things to think about when considering whether you support a riders right to choose whether to wear a helmet themselves or not. It should be up to the individual to decide. Either way, they'll have made the choice that is right for them. That is what the whole fight is about. The right to choose for yourself, or be told to wear a helmet "for your own good".
Catch you on the road sometime...