The cause of the deaths of three children in a single vehicle crash near Sudbury Ontario continues to be kept secret. What is known is that the dead children, aged 11, 10 and 6 were accompanied by a fourth child, aged 10, who sustained “undisclosed, life-threatening injuries”. The children were also accompanied by two adult women, aged 45. One adult, the driver, was uninjured while the other sustained minor injuries. These facts are disturbing.
It has been mentioned in a previous article on this website that the noted fatalities are not consistent with the severity of the visible damage to the collision-involved 2007 Honda Accord. Admittedly, the investigating police only provided a single photo showing the front and right side of the vehicle. Further damage might exist to the other portions of the vehicle than cannot be seen. Yet the existence of additional damage is not likely given the general explanation of the circumstances. The visible crush was of moderate magnitude with no indication of disruption of the occupant compartment. Broad indicators of collision severity such as the displacement of wheels, roof pillars and windshield fracture all confirm the moderate severity of this collision. This is further evidenced by the report that the driver was not injured while the other adult passenger sustained only minor injuries. Why is it that the two adult occupants of the vehicle sustained such mild consequences yet the children did not? That is the question that no one is asking.
Here is a brief review of basic principles.
Collision injuries and deaths are caused primarily by the sudden change in speed of a vehicle. Technically this is more accurately described as the “change-in-velocity” of the vehicle. Velocity is similar to speed except that it also has a directional component assigned to its definition. And knowing this directional component is important in a technical analysis. The change-in-velocity of a vehicle in a serious collision can take place in just over a 10th of a second, or just over 100 milli-seconds. And this timing can be as long as half a second, or 500 milli-seconds, in extremely long collision sequences, like severe sideswipes for example. This timing is important because it has an effect on the acceleration pulse and collision forces. In injury assessment it is really the acceleration pulse that is experienced during the change-in-velocity that is the factor that determines the severity of injury. Acceleration is the rate of change of velocity. Technically, there is no such thing as “deceleration” but this is referred to as a negative acceleration. So we either have positive acceleration (i.e. depressing the gas pedal) or negative acceleration (collision). But let’s continue to use the term deceleration as this is more easily understood.
Given a certain velocity change a vehicle could sustain different rates of deceleration during the time that the vehicle is changing its velocity. Ideally, we would want the vehicle to sustain a constant rate of change in velocity so that the deceleration is relatively stable. But this theoretical ideal does not occur in real collisions. Let us use an example.
We can use the example of a velocity change of 40 km/h that is completed in a 1/10th of a second. 40 km/h is the same as 11.11 metres per second. So we say that the vehicle loses a velocity of 11.11 metres per second. However, because this change occurs in 1/10th of a second this is equivalent to a change of 111.1 metres per second, it’s just that the change does not exist over the entire second.
We also need to know that deceleration is defined with respect to the earth’s gravitational pull, which is at a rate of 9.81 metres per second squared, and this is referred to as one “g”. So now we can divide the 111.1 metres per second by 9.81 and arrive at an average deceleration of 11.3 gs. This is the average rate of deceleration that could be expected if the vehicle was slowed at a constant rate. But that is not what happens in real collisions. There are soft and stiff spots in vehicle structures and other factors are involved such that the average deceleration is not the same as the peak deceleration. It is the peak deceleration that matters in injury causation and this peak deceleration for the vehicle structure will be different than the peak deceleration experienced by the vehicle occupants. And individual occupants will sustain different peak decelerations. And peak acceleration needs to occur over a sufficient time in order to be relevant to injury causation.
The benefit of an airbag, seat-belt or child restraint is that these systems help the occupant’s body to ride down the change-in-velocity in a controlled manner, applying the pressure of contact to structures of the body that can withstand that contact, while also lengthening the timing of that ride-down. In a nutshell, all these devices start the deceleration of the occupant’s body at an earlier stage and not much later than the start of the vehicle’s deceleration. And this additional time of deceleration is what allows for overall lower rates of deceleration.
Other factors can mess-up this relationship between change-in-velocity and injury causation. So undesirable factors such as occupant ejection, structural intrusion, fire or vehicle submersion in water need to be taken into account. And the actual frailty of the individual needs to be taken into account.
While seat-belts, airbags and other technological advances provide superior protection in the vast percentage of collision scenarios, not all persons can be protected in all collision scenarios. This is where we come to the issues of the three fatalities in the Sudbury collision. Restraints do not just magically prevent death and injury. There must be an active involvement of the vehicle occupant to ensure that the systems are able to function properly. So drivers must keep their bodies far enough away from an exploding airbag so that they do not sustain airbag-related injuries. Proper types of restraints must be installed for the protection of children, and generally, the proper restraint for the occupant must also be worn properly and this requires an active participation by the occupant.
One of the true tragedies of life is that we ask persons to wear their seat-belts but then we do not inform them that they must also wear them properly. This does not mean obvious mis-uses such as placing the shoulder (torso) webbing behind the back. But there are critical matters such as placing the lap webbing down low and tight. It also involves examining the type of clothing being worn and whether this will cause undesirable slack in the system. Even with the installation of “pre-tensioners” that pull a webbing tight, those pretensioners can tighten the webbing for only a few inches and if slack is extreme the benefit of the pre-tensioner could be substantially lost.
For children we seem to refuse to recognize that “one size does not fit all”. Government vehicle compliance testing primarily involves front seat “dummies” with little or no testing of restraint systems in the rear seat. Yet we tell parents that it is dangerous for children to ride in the right front seat because of the potential of airbag injury. So why is it safer to put a child in a non-fitting seat-belt? It took us an unacceptably long time to recognize that we needed the addition of booster cushions to transition a child from a child seat to an adult seat-belt. Yet we still do not understand that vulnerability exists for those children that are exiting the booster seat phase of their growth and are now going to wear adult seat-belts. We fail to recognize the extreme danger in Canadian winters when we take our 10-year-old child, wearing a slippery, nylon over-coat and tell them to put on their seat-belt in the back seat. What do we expect will happen? Will a magical “restraint fairy” come along and ensure that the restraint will fit the child, that the lap belt will not slip on the nylon coat, that there is no excess slack, that the child has placed the restraint system properly? While this commentary is approaching inappropriateness it cannot be helped in this environment when discussion and education is so crucial to the safety of innocent children. While we must feel empathy for the families who have lost such innocent children we fail in our obligation to protect future children, and to prevent the misery of future families, when we keep the causes of child deaths from public awareness.
Even from the basic facts, the four children in the Sudbury collision could not have been transported in safety. As neither of the four children could safely be seated in the right front seat this means that they all had to be seated in the rear seat. A 2007 Honda Accord does not have four seat-belt systems in the rear seat. No passenger car has four seat-belt restraints in the back seat. So, at a minimum, at least one child had to be unrestrained.
A 2007 Honda Accord is not equipped with seat-belt pre-tensioners so even if three of the children wore seat-belts they were in jeopardy. These dangerous conditions need to be identified so that future children are properly protected. In recent years there has been considerable discussion about the need for seat-belts on buses, including school buses. The need for seat-belt usage on inter-city coaches may be desirable as they will keep occupants within the safety cage of a bus but the structural integrity of such buses needs to be improved. With respect to school buses however there is an additional danger of children not being properly restrained and/or not being restrained by a properly fitting restraint. The potential of increased injury and death to children from such occurrences is not exaggerated. This is why it is important to get to the bottom of how and why the children in the Sudbury crash died. If these deaths are related to restraint system problems then they are an important warning of what could occur if all children are forced to wear seat-belts on school buses, regardless of whether they will protect the children.
The site of the collision on Hwy 17 was not properly identified in the news media. While reports indicated it was near to and east of Hwy 144 an examination Googlemaps does not provide the type of geometry shown in the police photo that exists anywhere near Hwy 144. After further examination, the most likely location of the site is likely about 780 metres west of Hwy 24 or about 2.5 kilometres east of Hwy 144. The two figures below show views of this location taken from Googlemaps.
If this is the actual collision site then one can see that there is no rock cut on the right side of the highway but there is one on left, or median side. Yet the single photo of the Honda Accord appears to show an area of maximum crush at the right front and then a secondary area of damage at the right rear corner. The most logical explanation for the combination of these facts is if the Honda rotated counter-clockwise as it exited the road surface. This Honda would have travelled toward the rock cut in the median. Due to the substantial rotation the right front of the Honda Accord would have struck the rock cut and then, during further counter-clockwise rotation, the vehicle would strike the rock cut with its right rear corner.
It is not known whether the vehicle came to rest where it is shown in the OPP photo. However this could be a reasonable possibility if the vehicle continued its rotation and bounced off the rock cut returning to the road surface.
If this is a correct interpretation of the sequence of the collision event then there should be no other direct damage located on any of the vehicle’s surfaces that are not shown in the OPP photo. This should cause further concern as it would solidify our previous comments that the damage to the vehicle is not consistent with the resultant deaths of the three children.
A witness who came across the collision was quoted as saying “It was snowing a little bit, the roads weren’t ideal, but they weren’t bad”.
And similarly a police spokeswoman stated that the weather conditions at the time of the crash were reasonable with only a light dusting of snow on local roads. But it can be noted that the officer said nothing about the surface condition of the Hwy 17 at the accident site. As a standard procedure OPP will conduct a series of skid tests in the vicinity of where a vehicle approaches impact. Such skid tests would reveal the slipperiness of the road surface. But there was nothing mentioned about the skid tests nor whether any testing revealed the quality of the road surface. This is important because, if the Honda Accord rotated to the degree that its right front struck the rock cut in the median then something had to occur to cause this substantial rotation. Vehicles travelling on a straight highway, on a new asphalt pavement do not suddenly rotate in the manner that the Honda Accord would seem to have done. However a slippery road surface could explain why the rotation occurred. A road surface need not be covered in many inches of snow before losing a substantial amount of its friction force.
There are many questions that need to be answered with respect to this tragic collision, yet no such answers have yet been provided.