Speed Can Be Irrelevant In Injury Causation
Was this vehicle travelling “fast” or was it involved in a high-severity impact? Is there a difference? Does the difference matter?
While the title of this article sounds completely wrong it is an important lesson to understand why it is mostly right.
It is never convenient to discuss the results of real-life motor vehicle tragedies because they always involve real people. Yet a failure to educate ourselves from these results often leads to future tragedies that could otherwise be prevented.
The lesson in the present article is an attempt to clarify a common misunderstanding that the travel speed of a vehicle is what causes injury. In other words, if you are travelling faster you will sustain a higher severity of injury. This fallacy has been growing deeper roots in some recent research and has been picked up by news media resulting in unreasonable demands for policy change that hinders true improvements in road safety.
The above photo shows a recent tragic scenario where an SUV carrying 3 occupants crashed into a tree on Webb Road in Durham, Ontario resulting in one fatality. The photo of the vehicle at its final rest position shows that its driver’s door was pressed against the large tree and there was massive crush into the driver’s seating area. Most persons looking at the photo would conclude that the SUV must have been travelling at a tremendous speed in order to cause the resulting damage. In reality these views of the vehicle cannot be used to draw that conclusion.
Let us examine a typical scenario where an SUV is travelling on a typical Ontario highway with a posted maximum speed of 80 km/h. Let us say that we know its speed was 100 km/h. As it passes through a curve the driver loses directional control of the vehicle and it begins to rotate while the driver steers left and right to regain control. This action may take place over a distance of 100 metres. While this “yawing” motion is taking place the vehicle is losing speed, often at a rate between 0.2 and 0.4 g. Taking an average of 0.3 g in that distance of 100 metres the vehicle would lose a speed of about 87 km/h. The vehicle then strikes a tree with its driver’s door and the vehicle comes to rest against the tree. The relatively low speed of impact results in relatively minor damage but because the tree is pressed against the driver’s window, and because the driver’s body moves toward the point of the application of the force, the driver’s head strikes the tree and the driver dies. Looking at the minor damage to the vehicle many would scratch their heads and say “there must be something wrong here. A driver should not die from such a low speed impact”.
We then look at a second example, the same SUV is driving the same road at 100 km/h in wintertime and the same loss-of-control takes place due to an icy road surface. Because of the ice the vehicle might slow down at a rate of only 0.05g over the 100-metre distance. Calculating the speed loss we obtain about 36 km/h and the vehicle is still travelling at about 64 km/h when it strikes the tree. But due to the luck of chance the impact occurs just behind the driver’s door and the massive intrusion to the structure is located behind where the driver is seated. The driver survives and everyone wonders: “Wow, how could this person survive such a high speed impact?”.
What can we learn from these results?
In both instances the SUV was travelling at the same speed. But in the first instance the vehicle lost a substantial amount of that speed due to its sliding on a surface that was able to dissipate (remove) its kinetic energy. Thus the initial speed of the vehicle was not relevant. What was relevant was the speed when it struck the tree. Not only was the impact speed an issue, but also the location of the application of the force: directly at where the driver was seated.
In the second impact the SUV’s speed was not reduced appreciably before the tree impact and the impact speed was much higher. But because the impact was behind the seated position of the driver the crush or structural intrusion was not applied into where the driver was seated. The collision appears to be very severe but the driver survives.
This illustrates the fallacy of using initial speed of a vehicle in discussing the danger of sustaining significant injury. The initial speed in not the important factor, it is the impact speed that is important. Furthermore it is the change-in-speed that is important. As we dig deeper we then begin to add the fact that it is how quickly that change-in-speed occurs that is the critical factor. And we then add that it is also the direction of force, the existence of pre-impact rotation, and so on, that need to be taken into consideration.
Now, before ending this discussion we need to clarify some additional points. When we talk about injury causation we do not discuss change-in-speed. Instead we use the term “change-in-velocity”. Speed is a scalar term that does not give an indication of the direction of that speed. Velocity is a vector and is a more complete term because it has the associated direction applied to its definition. So a speed may be “100 km/h”, while a velocity would be “100 km/h in a north-west direction”. The directional component is an important matter that cannot be ignored.
We then need to add that it is not the change-in-velocity that is relevant but how quickly that change-in-velocity occurs. So this is where we introduce acceleration. Acceleration is the rate-of-change in velocity.
And further still be might add that the change-in-velocity or acceleration experienced by the body of the vehicle is not the same as the change-in-velocity or acceleration experienced by the occupant inside the vehicle.
These are just some of the basic and simple issues that need to be understood when discussing injury potential and the travel speed of a vehicle. We need to understand that we cannot equate travel speed with injury causation. There is no direct relationship between these terms. The title of this article is somewhat misleading because, indeed, if you are travelling 100 km/h you possess the potential ingredient for causing serious injury and death. But it is not true that you will sustain serious injury or fatal injuries just because of that travel speed. The issue is more complicated than that.
Another issue that has been prominent in recent fatal collisions is the issue of initial speed, structural separation and injury causation. This point is highlighted by two attention-grabbing collisions that occurred, one Edmonton Alberta, and one in Toronto Ontario the past couple of months.
In an article that was posted to this website on July 5, 2020 we attempted to explain that three occupants of an Audi were killed after impacting a Starbucks retail outlet, not because of the vehicle’s speed, but because of the disintegration of the vehicle’s structure. Again, this was meant to highlight the important issue that we need to look at the severity of the impact in terms of the change-in-velocity experienced by the vehicle. When there is a lack of evidence showing that a large amount of kinetic energy was dissipated we need to ask more questions about why a fatality occurs.
This concern was repeated once again in another Audi impact that occurred in Toronto, Ontario. The driver of an Audi lost directional control of the vehicle and it rotated into the path of a Jeep SUV. It appeared to all involved that the speed of the Audi, as its driver lost directional control of the vehicle, was all that mattered. The fact that the Audi separated into two pieces seemed acceptable because the Audi was travelling at a high speed.
While the last views of the Audi appear to show an unsurvivable amount of destruction, the driver reportedly survived as well as one of the three occupants. So how severe was this impact? Vehicle occupants die because they are involved in collisions where a vehicle sustains a high change-in-velocity. Did this Audi sustain a high change-in-velocity. If so, why did two of the three occupants survive?
Many vehicles contain weak points in their structure. When a vehicle is struck in the side, in the manner suggested in these photos, structural separations occur. Not just today, or yesterday, or last year, or 10 years ago. Vehicles have been separating like this since they began to be manufactured as unibodies.
We do not have the privilege of examining the details of this crash. Only the investigating police have that opportunity. This leaves us at a disadvantage as we can only use the photos of the damage and the vehicle rest positions to support our comments. However collisions of this type often happen in a recurring manner. When a vehicle rotates out-of-control, it travels into the opposing lane while continuing that rotation. The manner of contact to the vehicle’s side is not the same as the scenario encountered in an intersection collision. Nor is it in the manner in which vehicle crashworthiness is tested in government crash tests. It is likely that the pre-impact rotation of the loss-of-control vehicle is part of that difference. It has also been observed that the direction of the impact force contains a component that involves “sliding” or sideswiping across the struck surface. The combination of these factors leads to a loading of the side structure in a manner that causes the separations observed in the Edmonton and Toronto collisions. This weakness in the vehicle structures causes massive destruction that, to the average onlooker, appears to be consistent with a high speed of a vehicle and the crashworthiness of the structure is never questioned.
To summarize, it is an attention-grabbing comment to suggest that speed is not relevant to injury causation. In one way the comment is in error because it is the speed which provides the potential for injury causation. But we must be careful to understand that speed alone is not the critical factor. It is what happens to a vehicle’s motion during an impact that matters in injury causation. And it is what happens to the body of the vehicle occupant which makes contact with the vehicle interior that matters in injury causation. These issues may be completely irrelevant to the ground speed of the vehicle.
Tanker Truck Through Guardrail Shows Inadequacy of Roadside Barriers
This OPP photo of a tanker truck collision fails to highlight the important status of the guardrail. The guardrail is still attached to the concrete bridge abutment and its anchorage posts are generally in line. This suggests that the truck rode over top of the guardrail.
On Friday, August 14, 2020 the OPP Twitter account informed the public of the closure of Hwy 401 west of Kingston, Ontario due to a collision involving a tanker truck which had spilt liquid tar into a creek. Photos were attached with the notification, the one shown above, and two others shown below.
Regardless of the original circumstances which led to the tanker truck’s travel toward the roadside, there is evidence in the above photos to demonstrate that the manner of interaction between the tanker truck and roadside guardrail was inadequate.
Depending on varying circumstances the super-highway which is Highway 401 carries large volumes of heavy trucks. Often truck volume may exceed the volume of all other traffic. At the same time Highway 401 is at the peak of the level of service of all highways in Ontario. It is given the highest level of maintenance and design. When more than half of the vehicles on this highway are heavy trucks then there should be a focus on creating a highway environment that protects the safety of truckers and their trucks. It is not a sudden revelation that various roadside barriers are installed to reduce the severity of collisions and therefore they should reduce the severity of heavy truck collisions. Heavy trucks have driven on Highway 401 for decades and roadside barriers have existed for decades. What is missing is the acknowledgment that a large number of barriers along Highway 401 are inadequate in their ability to reduce the severity of heavy truck collisions.
With respect to the collision shown in the photos above, it is clear that the tanker truck passed through or over a guardrail before it entered the creek spilling its cargo. Although police reported that the truck driver did not sustain any injury this was likely more due to luck rather than the result of designed safety systems. The collision resulted in a costly cleanup but it could have been worse if the cargo was of a more noxious or explosive base.
When we look at the photos we note that the guardrail impact was close to a bridge abutment. A guardrail is generally strengthened at its junction with a bridge abutment primarily so that a striking vehicle can be deflected from impacting the very stiff and immovable concrete abutment. When looking at the first photo it shows that the end of the guardrail is still attached to the concrete abutment and that is a desirable outcome. Yet we still see evidence of contact to the concrete. We also see that the wooden anchorage posts of the guardrail are at various angles but they are generally in line and do not appear to be broken away. This indicates that, at this location, the tanker truck did not drive through the guardrail but rode over top of it. The first photo is shown again below.
If we look in the background of the photo above we can see that the rear wheels on the tanker trailer are mutilated. These are the left (driver’s) side wheels. A close-up of that area is shown in the view below.
The severity and location of such damage is not consistent with the impact of the rail but is more consistent with the impact of the concrete bridge abutment shown in the foreground. Thus we gain insight into how the truck and trailer passed over top of rail and made a glancing contact with the bridge abutment. This interaction is not by design, it is by chaos.
We would like to see the condition of the portion of the guardrail on approach to the bridge abutment but police did not a provide a good view of that area. A close-up from of the first photo is shown below but it provides little assistance. It is possible that a length of rail can be seen lying on the grass slope but it is difficult to say.
Additional information can be obtained from examining the site with Google Maps. The photo below shows a general view of Highway 401 from Odessa to Kingston. The town of Odessa is located just to the left of the centre of the photo and it shows that Highway 401 is straight for a substantial distance until the collision site where the Highway contains a significant curve.
A closer view of the substantial curve is shown below. The orange circle indicates the location of the collision site.
And a further close-up view of the site is shown below, again with the orange circle indicating the location of the collision site.
The Google Maps view below is looking east on Highway 401 and approaching the collision site. The extent of the sharp curve can be appreciated.
And again, the view below shows the collision site looking eastward, upon approach to the bridge over the small creek. Here we can see the portion of the guardrail that was struck by the tanker truck. The crucial information needed to confirm the adequacy of the rail is its height. But that is unknown.
In many instances the anchorage posts of a railing are wooden and they become rotted through age. Although it is difficult to see, the anchorage posts of the rail shown in the above photo appear to be of a metallic/aluminum material and not wooden. Thus an explanation for the truck’s passage through or over the rail cannot be provided without actually being at the site and being able to examine the damaged system.
The pre-crash status of the guardrail and its connection with the concrete bridge abutment is shown in the photo below. In some instances there is an improper joining of the rail to the abutment.
A closer view of that junction is shown below. At face value there does not appear to be an improper connection of the systems. Yet there appears to be piece of the concrete abutment missing at its upper corner. This would suggest that there was a previous impact to the abutment. That outcome should be of concern. But again, without the ability to conduct a further investigation nothing further can be accomplished in this review.
It should be part of the police reconstruction activities to assess such roadside structures especially when it is clear that a structure has allowed a vehicle to pass through, or over top of it. Such results are life-threatening. No less life-threatening than if those police had detected an impaired driver or a defective vehicle. Regrettably that documentation of roadside systems is not happening.
The drivers of heavy trucks and buses are at increased danger because roadside structures are not designed to interact with these taller and heavier vehicles. More importantly, intercity coaches may carry dozens of passengers and the threat of multiple fatalities should make it even more important to protect their safety. At present there is no official acknowledgment of the special dangers that exist to the occupants of any heavy vehicle on a high speed expressway. Collisions like the present one are simply ignored without appreciation that, sooner or later, those lucky outcomes will end.
After Questioning of Bomb Report Police Admit it Was a Fire
There may be legitimate reasons why police are not forthcoming with further information on the fatal “explosion” that killed a man in a car in front of the Kitchener-Waterloo courthouse on Friday, August 14th, 2020. In an article posted to the Gorski Consulting website on August 15th we questioned the reports that the resulting damage to the vehicle was as a result of a bombing, as per an IED. We noted that the physical evidence did not match what was being reported.
Now various official news agencies are reporting that police have changed their reports and are now indicating that the damage was caused by a fire but that it was deliberately set by the deceased.
This is the unfortunate circumstance that there is no independent investigative agency that can inform the public on this matter outside of what police say. Changes have occurred in the news media such that news organizations are centralized and a vast number of small independent agencies no longer exist. At the same time those few news agencies that exist have limited field personnel whose historical job has been to investigate and report, via news articles, to the public. In many instances news media simply report, word-for-word, from police press releases without conducting further inquiries as to the accuracy of those releases. Thus with respect to the present case, there is no information on the identity of the deceased, why his/her actions led to his/her death, or if indeed the person died via other means than what has been reported. The democratic checks and balances that allow information to come from various sources and prevent the manipulation of reported information is being challenged. Social media cannot replace proper, professional, investigative journalism.
Was it a Death of a Bomber or a Simple Car Fire?
We can swallow what we are told fully and completely or we can critically evaluate what we are told. Such is our intent is commenting on the reported explosion of a car in front of the Kitchener courthouse on Duke Street yesterday.
The site photos show the exploded vehicle with a tarp over it and we can also see the surrounding area. Comparing the results to what is typical in a simple car fire those results do not appear to be much different. There is no massive debris field. There are no pieces of metal strewn about a large perimeter. Even though the tarp covers the vehicle its structure can still be detected underneath and there does not appear to be a large extent of structural deformation. A closer view of the vehicle is shown below and confirms the relatively minor results of the “explosion”.
Unfortunately there are many incidents of vehicle fires that remain unexplained, some involving fatalities. The results of such incidents are thrown of out the public’s view with yesterday’s trash as new developments quickly grasp the public’s attention. Rarely is meaningful information provided so that such incidents can be prevented before a tragedy occurs. The repeated scenarios are like the surroundings of a ten-pin bowling alley where pins are destroyed and the responsibility of police and news media is simply to re-stack the pins for the strike of the next bowling ball. The fact that real-life deaths occur seem to be of minimal importance except that they make great news.
An incident such as the one discussed here needs better explanation. What evidence is there that this was an intended (or unintended) explosion of a bomb by a bomber? Could it be something that exploded carried by an ordinary member of the public? The incompetence (or corruption) of official entities in Beirut Lebanon earlier this month led to a massive explosion that killed hundreds or innocent citizens while injuring thousands more. While Lebanon may be another country the results of mistakes, negligence or downright corruption need to be kept in mind. Seemingly simple explosions or fires of a single vehicle need to be probed, not with paranoia that leads to uninformed conspiracy theories, but with logic and careful consideration.
Nothing Learned or Changed At Anniversary of Massive Explosion in London Ontario
Scene on the night of the massive explosion on Woodman Ave in London, Ontario on August 15, 2019. Miraculously no one was killed but several homes were leveled.
Yes there was a great deal of excitement when a good portion of the Woodman Ave block exploded in London, Ontario on August 15, 2019. The story made national headlines for several days. But what changes did it bring?
We know the incident started when an impaired driver rode the wrong way on a one-way road (Queens Ave) and struck the side of a residence at the location of a gas metre next to the driveway. It should have been a simple lesson to learn that locating gas metres next to a driveway is not a good idea for obvious reasons. And if that driveway is at the dead end of a street it is more liable to be struck simply because some driver could mistakenly miss the fact that the street was coming to an end – it has happened numerous times before in every city or rural location.
And if a driveway is narrow and it also contains a gas metre then surely this should be an even greater warning sign. It would seem that a reasonable approach would be to check various residences in a city like London Ontario to assess how many might have gas metres that are vulnerable to such repeated disasters. But were changes ever contemplated? Did anyone ever question whether it would be a good idea to conduct such a survey? Apparently not. Because another incident, almost on the anniversary of the massive explosion, occurred again, almost in the same circumstances, except luckily there was no explosion.
News media in London have reported that, on August 14, 2020, a pick-up truck struck a residence resulting in the impact of a gas metre on Grey Street in south central London.
One of the interesting observations from the news media information is that there was little damage visible to the home although the striking pick-up truck was at a somewhat unusual angle. This does not appear to be a massive impact to the house. Rather it looks something like a mistake that a driver made by bringing the truck too close to the house in the narrow driveway. We know the driveway is very narrow because we can look at it from views shown in Google Maps, an example shown below.
So, as a City representative, why would you allow the location of a gas metre within the very narrow confines of this driveway? Did anyone learn anything from the massive explosion that occurred in the City just a year earlier? Evidently not.
It is matters like these that show how we do not make corrections to dangerous conditions even though they have resulted in disastrous incidents and even though those incidents have been greatly publicized.
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