Report of rider injury

The fatal injury on the Schlitterbahn “Verrückt” waterslide has been reported as a decapitation.

Earlier accounts referred to a “neck injury”. Reporters enthusiastically parsed past Consumer Product Safety Commission reports and noted 28% of injuries in their dataset were head and neck injuries. They did not report that the CPSC data on amusement rides substantially overstates injury occurrence due to the inclusion of swan boats, ball pits, laser tag, corn mazes and other things that are not what you would popularly consider “amusement rides”. A study I published in the journal Safety Science in 2014 found the national estimate of actual amusement ride injuries was less than 2/3 of what CPSC data would suggest.

And let’s be honest: most of those head and neck injuries are concussions and soft tissue injuries like whiplash, perhaps a bump on the nose from impact due to abrupt acceleration or deceleration. Those are not habit forming and should not happen, but decapitation is a completely different situation. We shouldn’t consider this just another dot in the “head and neck injury” pie wedge.

I will note that I have no particular knowledge of what occurred in this case, and can only react to the reported descriptions. Some reports have questioned the condition of the restraint devices in the rafts. Some rides may not require any restraint at all, since the forces on the rider’s body are primarily gravity forcing them toward the seat. Restraints on many kiddie rides are mainly to prevent unsafe behaviour like standing up. If the rider stays in the correct position, the forces would not remove them from the ride. However, this slide has been described as having “air time” or forces up out of the seat.

On roller coasters and other rides that must comply with ASTM F2291 standard, rides must have a restraint device selected in appropriately to the forces on the rider’s body. When there are substantial forces away from the seat, not only will a restraint be required, that restraint may require redundant components, and locking mechanisms that the rider cannot open intentionally or unintentionally.

Riders who separate from a ride vehicle (due to ride acceleration or by climbing out intentionally) can fall or strike against objects in the vicinity of the ride can sustain more serious injuries than impact within the ride vehicle. It is critical on an amusement ride that the ride restraint and containment system (lap bar, seat belt) is appropriate to the ride, works properly, and fits.

The restraint must also fit the rider’s body. It is probably obvious that a rider who is too big to close the restraint or too tall to fit under the shoulder bar will not be able to ride safely. Riders who are too slender may be able to reposition into a dangerous position within the closed restraint, or even slip out from the proper seating position, due to ride forces. Petite riders inside a spacious restraint should ensure that they understand the forces on their body.

Restraints that open while the ride is operating present a grave danger. Even if they are just to deter impulsive behaviour, some riders may need that. If they are there to counteract ride forces, they have to work, every time.

The attractions industry is devoted to safety and I know that every single person in the industry has been thinking about this terrible event since it occurred, dedicated to making sure it cannot happen again.

Author: Kathryn Woodcock

Dr. Kathryn Woodcock is Professor at Toronto's Ryerson University, teaching, researching, and consulting in the area of human factors engineering / ergonomics particularly applied to amusement rides and attractions (https://thrilllab.blog.ryerson.ca), and to broader occupational and public safety issues of performance, error, investigation and inspection, and to disability and accessibility.