Enough is Enough, Part 6: Three-Point Seatbelts

As we learned from the Introduction to this series, tire manufacturers, motorcoach manufacturers and more recently a seating manufacturer have been sucked into lawsuits in which they did not belong largely because they refused or failed to effectively challenge the specious and childlike notions used by th4e victims’ (or plaintiffs’) attorneys to argue their liability. Because the driver of the operating company involved (a small, sloppily-managed and illegally-operated charter company, as is often the case in such accidents) fell asleep at the wheel, and his driving was impaired by drug/alcohol usage, the manufacturers and suppliers sued should never have been held responsible for the carnage. But since the operators’ insurance coverage fell far below the amount needed to compensate the victims for the litany of fatalities and serious injuries that occurred (as they similarly fail to in most catastrophic accidents), the plaintiffs’ typical  army of attorneys looked for other parties with “deep pockets,” and drew them into the lawsuit. In this particular catastrophic accident, the plaintiffs’ attorneys chose not only the motorcoach manufacturer, but following an easy, previous victory where that same company foolishly settled for $30,000,000, expanded its unchecked madness by also suing the seating manufacturer. And because the NTSB Report was so flawed, they also filed suit against two major international tire manufacturers. As noted, all of them, once again, caved in – this time, with the motorcoach manufacturer only settling for $18,000,000.

So that the reader may understand the legal dynamics to which this series of installments is targeted, this and the five previous installments provide and provided an extensive background about the accident and its investigation, and more recently, a two-series overview of lapbelts and seat compartmentalization – the latter needed as the introduction so that the reader can understand the pros and cons of three-point seatbelts which have increasingly been installed on motorcoaches since 2009 — largely because of the manufacturers’ fears of becoming codefendants in huge lawsuits where their and their  insurance carriers’ assets are at stake. This installment will examine the issues related to three-point seatbelts themselves. Finally, future installments will present the ridiculous arguments made by the plaintiffs’ attorneys and their experts (which, again, all these defendants apparently accepted in agreeing to settle the case), will address the outrageous impropriety of holding manufacturers and suppliers responsible for these accidents, and will outline a string of inter-related steps that these usually-undeserving victims of such lawsuits can take to defend themselves, reverse the increasing trend whereby they are included as codefendants in such lawsuits, and hopefully put a stop to this practice.

Characteristics of Existing Motorcoach Seats without Three-Point Belts

Part 4 of this series included a subsection titled “Compartmentalization and Containment” which, among other things, summarized the containment features of conventional motorcoach seating systems that help to greatly minimize rebounding and, to some degree, ejections – two phenomena of catastrophic accidents, particularly in those rare instances where the coach rolls over. Among the positive attributes of conventional motorcoach seats noted were:

  • Their armrests, when deployed in the upward position, provide lateral containment from side-impact forces, and significantly limit rebounding – although this comes at the cost of bludgeoning the passengers’ soft-tissue above their hipbones.
  • Their high seatbacks provide protection in rear-impact collisions.

 

  • They contain contoured, bucket seats: When the passengers’ buttocks sink into them, their hips are provided a degree of containment, at least from moderate forces exerted on them.
  • The thick padding of even non-compartmentalized motorcoach seats helps cushion passengers upon impact – significantly superior to the common plastic seats of transit buses – although this cushioning is compromised when, for example, tray tables are deployed.

While not nearly as effectively as genuinely-compartmentalized seats, these features at least constrain the movement of passengers out of their seats to some degree. And when these features are enhanced by the seats being genuinely compartmentalized (see Part 4 of this series for a detailed explanation of this concept), this protection increases significantly, particularly with respect to limiting and softening the impacts of rebounding. However, while this combination of features does more to contain the impacts of lateral impact forces than do, for example, fully-compartmentalized school bus seats, they do not do much to limit ejections, as rare as they are. However, the numerous downsides of three-point seatbelts and their related features (e.g., anchorages) considerably offset the benefits which three-point seatbelts provide. The downsides of these tradeoffs are discussed below. 

Comparative Mass

No type of seatbelt is without its downsides. This is particularly true with lapbelts, which can subject a passenger’s internal organs to serious trauma when engaged, and particularly in high g-force collisions, turn the passenger’s waist into a fulcrum and accelerate its movement into the seatback in front – often with lethal force.  Despite these significant problems, this technology is considered justified for smaller vehicles because the fellow-vehicles they strike are often of similar mass, and as a result, ejections are far more common than with full-size buses or motorcoaches, and rebounding is significantly more severe as well. In contrast, with vehicles typically 10 times the mass of those vehicles with which they most frequently collide, the crash forces are exponentially less: While not inversely proportional to the relative masses of the two vehicles, the somewhat esoteric mathematical relationship is similar. Thus, a vehicle weighing one-tenth the mass of the one striking it does not receive 10 times to impact forces, but closer to 100 times these forces. Inversely, a vehicle of 10 times the mass striking the smaller one receives impact forces close to one-hundredth the forces exerted on the smaller of the two vehicles. In simple terms, a large bus, truck or motorcoach striking an automobile or similarly small vehicle practically swats it out of the way, and in the larger of the two, rebounding is limited, and ejection almost unheard of. Other factors, such as bumper misalignment, or in some cases the lack of structure below the floor level (e.g., on many school buses and some bus conversions without luggage compartments), help the larger vehicles absorb these impact forces even more. As a result, the justification for three-point seatbelts on vehicles of larger mass are exponentially less-convincing than their justification for such installations on smaller vehicles. This is why, for example, seatbelts have only been mandated for full-size  school buses (whose body-on-chassis construction does not survive collisions nearly as well as an integrally-constructed transit bus or motorcoach) in six of the 50 States – and in three of those States, only extraordinarily-dangerous lapbelts are required. 

 

 

Active Versus Passive Benefits

As noted in the installments about three-point seatbelts (Parts 4 and 5 of this series), it is critical to recognize that the passenger must proactively apply a seatbelt of any kind to receive its benefits. If he or she does not – as many passengers do not (see section on “Usage” below), no benefits occur whatsoever. This is why the concept of “compartmentalization” has been endorsed in school buses: For compartmentalization to “work,” the passenger must do nothing but remain in his or her seat. The technology operates without the passengers having to do anything else.

Usage

Also as noted in Parts 4 and 5, studies of seatbelt usage by passengers of all ages have documented enormous variation, while to my knowledge, studies of adult seatbelt usage on buses and motorcoaches (at least in the United States) have revealed little of value. Frankly, I do not even know of any conducted in the United States. In contrast, a number of studies have been made of the use of lap belts by school bus passengers. Apart from these studies, usage is relatively high in the one State (New Jersey) that requires their usage – not merely their installation – as a regulatory matter, and where to some degree, this usage is highly-enforced. In contrast, one early study of lapbelt usage among school bus riders in Houston found that only seven percent of them used their lap belts.

Some interesting pro-installation arguments have cited the fact that individuals of every age have increasingly become used to wearing their seatbelts because of the decades of practice in personal occupancy vehicles (e.g., automobiles.). And studies of their usage in these modes have demonstrated that usage has increased regularly, albeit incrementally. In other words, because motorcoach passengers are becoming more accustomed to using three-point seatbelts in their personal vehicles, they are more likely to use them in motorcoaches. There is likely some truth to this argument. At the same time, reasons for not using this same equipment in motorcoaches exist. For example many motorcoach passengers sleep or nap during the ride, and many release their belts during this time to improve their comfort as they reposition their bodies. (I, for example, can sleep only on my side.) Another factor is likely to be the recognition that motorcoach accidents are rare compared to those involving automobiles, even though much of this knowledge simply reflects the far fewer number of motorcoaches on the road compared to automobiles and other significantly smaller vehicles – even though major motorcoach accidents receive exponentially more publicity than do automobile accidents.

While I have not examined usage studies in Europe and Australia, on whose motorcoaches the installation of three-point seatbelts have been required (since 1999 in Europe, and since the mid-90s in Australia), the cultural differences between these individuals and that of Americans is so radically different as so make such comparisons of marginal value. For example, residents of developed countries where phenomena like Climate Change and evolution are almost universally-accepted and rarely if ever challenged by genuine scientists are far more likely to use safety equipment than are U.S. citizens, many of whom have significantly less respect for science than do their counterparts in these other nations. For such reasons, it would be unrealistic to expect seatbelt usage studies of European or Australian motorcoach passengers  to provide much insight into their likely usage on motorcoaches in this country. 

 

Reclining Seatbacks

Reclining seatbacks pose yet another challenge to the effectiveness of seatbelts in motorcoaches, as they dramatically alter the “envelope of restraint” between the reclined seatback and those passengers seated in un-reclined seats directly behind them. Admittedly, this constraint is not as serious as it would be for lap-belts, which operate as fulcrums that accelerate the passenger’s heat into the seatback in front at highly-increased, and often lethal, speeds. Yet even while shoulder harnesses largely eliminate this feature of lap-belts, the tight seat-spacing in motorcoaches is such that a 95th-percentile male, for example, seat-belted into in an upright seat behind a reclined seatback in front of him, would still have his head smashed into the upper edge of the seat cushion in front, and at a much higher rate than had that seat (a) been compartmentalized, and (b) its seatback not reclined. Regardless, the need to eliminate this problem would require an increase in seat spacing by another seven or so inches – which would reduce the seating capacity in every motorcoach by roughly 30 to 40 percent.

Were this radical change not made, the impacts of the “envelope of restraint” on the tallest extremes of passengers, as noted in Part 5 of this series, cannot be ignored:

  • Even in a low g-force “stop short/slam-on-the-brakes” scenario, the passenger to the rear will not only fly into the top of the reclined seatback in front, but will likely do so head- or teeth-first – experiencing considerable injury, particularly if the seat and seatback in front have not been fully compartmentalized.

 

  • In a high-speed/high impact frontal collision with a large object (a fellow bus/coach, truck or bridge abutment, e.g.), this passenger will usually not suffer simply because his or her head will be smashed to smithereens.

 

 This reality – unevenness of usage — is among the reasons both I and NHTSA consider compartmentalized seating more important than seatbelts, particularly in vehicles with reclining seats.

Seat Loading

The installation of three-point seatbelts on motorcoaches would possess far fewer problems if (a) every single passenger used them, and (b) if every row of seats were fully-occupied. But it is certain that these conditions would rarely occur. Instead, when un-belted passengers fly forward from the inertial and/or centrifugal forces exerted upon their bodies, they would crash into the backs of conventional seats typically weighing about 80 or 90 lbs. (a pair of deluxe motorcoach seats possibly a bit heavier). But if the seat in front is occupied by two seat-belted passengers, the load on that seat would be quadrupled or quintupled, and the unbelted passengers flying into its seatback from behind would verily fly into a wall – even if a cushioned wall, or better yet, a compartmentalized wall. But this “wall” would be even more formidable if its seatback were reclined. Particularly because of both usage irregularity and seat-reclining irregularity, it would seem impossible to mitigate this risk.

 

 

Attachment Point Variables

 

As also noted in Part 5 of this series, the aisle-side legs of many motorcoach seats are mounted to the floor, while legs on the wall side, are mounted to the vehicle’s sidewall. These differences can affect both the deformation of the seat and its ability to remain in place following a collision, depending both on the collision orientation (i.e., frontal impact, side impact, oblique impact, rear impact or rollover) and the impact force. The loads placed on these attachment points from seats without seatbelts installed on them would remain far more consistent within every type of crash scenario simply because the passengers would fly off them, and thus, not affect the seat loadings. In contrast, once variables like the mixed usage versus non-usage of seatbelts, and the mixture of relined versus non-reclined are factored in, they would translate into differences in seat loading of hundreds of percents. As a consequence, the attachment points will need to be “overbuilt” to accommodate for the loads exerted on them in worst-case scenarios (e.g. fully-loaded, reclined seats struck from behind by un-seatbelted passengers). If they are not overbuilt to accommodate these extremes, the seats themselves could detach from the coach’s structure in certain scenarios, compromising the benefits of the seatbelts (when used) in the process. Further compounding this problem is the already-common practice by which seats are poorly attached to coach flooring in many models: Instead of attaching them to the vehicle’s tubular frame members, many seat anchorages are attached either through the floor via the use of long screws onto which the seat legs are tightened by wing nuts and large (often not large-enough) washers, or to sidewall panels via a similar approach. This problem reflects a common theme that flows through the many downsides of seatbelt installation and usage stemming from the irregularities in both seatbelt usage, seatback reclining variables, and obviously the countless problems presented by the almost endless variation in crash scenarios – including similar variation in the mass and structure of those objects with which a motorcoach might collide (including simply the ground in certain rollover scenarios).

 

Evacuation and Strangulation

 

These scenarios were also noted in Part 5 of this series. However, it must be noted that the risks involving evacuation and strangulation from three-point seatbelts would be far greater than with merely lap-belts. These risks would naturally be compounded in incidents “still unfolding” –such as where the vehicle has caught fire or has been completely or partially submerged. And the degree to which one could be increasingly entangled, as well as bruised, strangled or have limbs broken and organs crushed by the belts would increase, in a rollover accident, with every successive 90-degree roll. The problem of releasing oneself would be further compounded by the type of belts used on buses and automobiles – compared to the two-point lap-belt-and-buckle variations installed on commercial aircraft. Further, even at the end of the crash scenario, the vehicle is not always in an upright position, and particularly with three-point belts in rollover scenarios, the passengers could be suspended by the belts, making it exponentially more difficult to locate the release buttons, after which they would either be caught differently by the belts as they slid through them in an almost endless variation of positions, and if lucky – or not – then fall to the side of the bus that currently comprised its “floor.”

 

Further, many release buttons become “sticky” after continuous use. Not only would mitigating this translate into several minutes of additional time to detect during every pre-trip inspection, but possibly removing the bus from service, or limiting the use of a seat or more – assuming that the driver was diligent enough to detect the problem, and his or her supervisor honest enough to responsibly address it. Clearly, the majority of charter operators and drivers most commonly involved in catastrophic motorcoach accidents hardly fit this description. Further, given the fact that roughly 60 percent of motorcoach passengers are elderly, while another 30 percent are schoolchildren traveling on field trips, these difficulties would be compounded by the exaggerated shortcomings of the majority of the vehicles’ passengers: Not only would their internal organs and other parts of their bodies be more traumatized by the multiple impacts with these belts as they twisted and turned within their net, but they possess far less intellectual capacity to escape from them than would a normal, able-bodied young or middle-aged adult. So while these concerns would likely be far less for passengers like acrobats or Navy Seals, such individuals clearly represent only a tiny fraction of regular motorcoach passengers.

 

Belt Thickness and Weight

 

In order to mitigate many of the problems inherent in seatbelts, their width would have to be increased so that the impact forces would be distributed to much larger areas of each belted occupant’s body – particularly the waist-belt section of the belt, which tends to crush internal organs upon their deployment, especially when the passengers are small children. This increase in belt width (and possibly strength) would clearly translate into more cost and weight, although not significantly enough to argue against the installation of three-point belts by themselves. But they would also impede evacuation via the use of “belt cutters,” which otherwise can slice through a conventional lap-belt in a nanosecond. In contrast, accomplishing this feat for a three-point seatbelt system — much less following a catastrophic accident where either or both the driver and the vehicle are disoriented — would become exponentially more difficult, and in some cases, impossible.

 

Wear and Tear

 

As noted also in Part 5 of this series, the flexing and stretching characteristics of belt materials differ greatly, affecting the degree to which they inhibit their occupants’ movement. However, these belts are stretched, to some degree, every time the vehicle brakes or even decelerates significantly. As a consequence, their strength and composition is marginalized tens of thousands of times, or more, depending on the replacement intervals — over the course of a belt’s existence. So after tens or hundreds of thousands of braking or deceleration events, the materials tend to stretch. Even with the best intentions of replacing them when they are compromised to a certain point, there are no criteria or devices available for determining at what intervals this replacement should occur. This determination is further camouflaged by dirt, inconsequential fraying, and other aspects of a seatbelt’s normal wear-and-tear which tend to disguise the belt’s containment capabilities just as they would compromise them.

 

 

To a similar extent, this phenomenon would affect belt buckles — not only from the constant tugs on them, but also from the myriad of latching and unlatching episodes every time a passenger buckles or unbuckles his or her seatbelt. As a critical part of the seatbelt system, these buckles would, as a safety matter, have to be examined during the coach’s pre-trip inspection and post-trip inspection check-out – adding considerable time to this exercise, at least on those occasions where a driver would actually perform it. As noted, the operators involved in most catastrophic accidents, and whose vehicles and operations are often found to involve dozens of regulatory violations that have been ignored, are the least likely to perform such procedures. In contrast, their performance would add additional costs to those safe and responsible operators who comply with it. It is one thing to examine the handful of seatbelts and buckles on a paratransit vehicle used to transport a few extremely vulnerable individuals whose retention in their seats or wheelchairs is critical. But it is another thing to examine 47 to 55 such belt systems and buckles on a motorcoach carrying only a small fraction of passengers at such risk.

 

Passenger Variation

 

Despite their dangerous downsides on large vehicles, properly-fastened lapbelts are at least applicable to most passengers (at least on light-weight vehicles) given the fact that, even without shoulderbelts, they would likely prevent ejection. But the same is not true of shoulderbelts. While they indeed represent an important improvement over lapbelts to the degree they greatly reduce the “fulcrum effect” in all but the tallest passengers (given the reclining feature of motorcoach seats), there are a number of passengers whose health and disabilities would be significantly compromised by the addition of a shoulderbelt, and were they independent, it would be wise to omit them when attaching the lapbelt. Among these passengers are those with neck and upper vertebrae problems, broken arms, upper arm and shoulder injuries, and pregnant women, to name only the most obvious. Yet as currently configured, most three-point motorcoach seatbelts I have seen consist of a single piece integrating and joining three straps (two laps belts and a shoulder belt). In contrast, the vast majority of seatbelts for wheelchair occupants employ a separate shoulder belt. The point is, there are many passengers for whom lapbelts are appropriate (notwithstanding the plethora of reasons against their installation and usage noted in this installment) yet for whom shoulder belts are not. In order to accommodate these individuals’ specific needs and problems – which may be apparent to neither the passenger nor the driver – the shoulderbelt section must be attachable separately from the lapbelt section. This reality would require a significant change in the configuration of most of the three-point belt systems currently employed. It would also complicate many of the other factors noted in this installment, including either the addition of yet another, separatesecurement point for the shoulder harness, or another even more complex modification of the three-point belt system.

 

Finally, the one-size-fits-all nature of lapbelts is easily modified by their adjustable nature, and even the existence of a “lapbelt extension.” The same would not be true of a three-point belt, particularly when a morbidly obese passenger is involved, or a considerably deformed yet ambulatory or semi-ambulatory passenger not using a wheelchair is involved. Because 60 percent of motorcoach passengers are elderly, the “discomfort factor” of many members of this class will contribute to their non-use of the belt system, thereby providing even less justification for its costs and the many other tradeoffs its installation would involve, as noted.

 

Points of Intrusion and Intra-vehicle Movement Constraints

 

In rare accident scenarios, bus and motorcoach passengers are able to avoid being killed or seriously injured by quickly moving away from the most-dangerous “zone of intrusion” created by a colliding vehicle, particularly where that vehicle is approaching the motorcoach-in-question from the side. One example of this scenario was the famous Fox River Grove school bus accident in 1995, where unbelted students seated in the section of the school bus sitting on the railroad tracks were able to jump out of their seats and dash to other parts of the bus before the oncoming freight train barreled into the “zone of intrusion” at the bus’ midpoint. Young students observing this phenomenon likely would have been far less successful performing this maneuver had they needed to first unfasten their seatbelts, much less three-point seatbelts. So too would be elderly and/or disabled passengers who, as noted, comprise roughly 60 percent of all motorcoach passengers, although in fairness, these passengers would likely have a hard time quickly changing seats even if unbelted. But the 30 percent of motorcoach passengers comprised of schoolchildren certainly would not.

 

Carryover Effects

 

Also as noted in Part 5 of this series, the tendency to not use a seatbelt on a motorcoach may “carry over” to that same passenger not using one in an automobile or lightweight van or minibus, where the use of seatbelts is of critical importance because of the similar mass of vehicles and other objects with which it would most likely collide. This would be particularly true if the motorcoach seat were compartmentalized and, if the passengers knew it, would be even less likely to employ their seatbelts.

 

Anchorage Strengths and Related Factors

 

If a seat were to increase four- or five-fold in weight because its two passengers would now fastened to it by a seatbelt of any kind, in order to keep the seat itself from ripping out of the floor, one would have to quadruple or quintuple the strength of the seat’s anchorages, as well as reinforce the seat cushion and seatback so that they are not deformed by such increased loads. This increased strength adds considerable cost to the vehicle as a purchasing matter. But the added weight also adds to its operating costs for two or more entire decades of usage, likely translating into tens of thousands of dollars in additional fuel and maintenance costs, including increased tire and brake wear, and their more frequent replacement.

 

In noting this particular challenge, it must be recognized that the anchorages of seats not even loaded with seatbelts are simply attached through the floor, and/or wall-side legs through sheet metal on the side walls, via a network of screws, nuts and washers. Yet even with seats not quadrupled or quintupled in weight by “loading” them with seat-belted passengers, seat legs have been known to rip out of the flooring and sidewalls in many catastrophic accidents – including two which I examined as an expert witness. Were one to multiply the “loads” of these regular seats four- or five-fold by adding three-point seatbelts to them, and assuming that many of the passengers would use them, the responsibility for beefing up the anchorages would be compounded by the absolute necessity for tying them into vehicle frame members.

This requirement would present a formidable challenge for body-on-chassis varieties of motorcoaches with a sparcity of under-floor frame members, (much less not spaced according to seat-leg intervals), few or no diagonal frame members, and often thin, tubular vertical frame members, or even non-tubular “C”-channels supporting the sidewalls. To ensure compliance with this need, another entire FMVSS certification section would have to be either created, or an existing one significantly modified – whereas now, no such requirement exists. Once three-point seatbelts are added to the anchorage equation, such changes would be appropriate, even if they have not yet been promulgated to accommodate the near-complete shift to three-point belts on motorcoaches that began roughly in 2009.

Otherwise, were one to “adjust” the vehicle to offset this added weight, he or she would have to remove at least one bench-seat of passengers, if not two, and/or reduce the luggage carried by the vehicle. Particularly in operating scenarios involving a considerable amount of luggage, this trade-off would trigger cost dynamics that would greatly constrain an industry already operating at a thin profit margin. Further, and realistically, the constraints this added weight and cost would place on the industry would more than likely lead to a plethora of increased regulatory violations and other safety compromises at the operating level – including possibly overloading the front suspension system [the rear suspension system is no serious risk from this added weight because of its dual tires and often tandem axles and their tires], but otherwise leading to more deferred maintenance, as well as innumerable cost-saving measures throughout operations, the most dangerous of all being violations of hours-of-service requirements, and when not, violations of other fatigue management principles that would compromise the drivers’ alertness level. 

As an alternative, the vehicle’s suspension system would have be beefed up – at considerable cost – possibly including the use of a higher-cost, more formidable class of front axle, not to mention possible other changes in the supporting members of the suspension system. To be fair, both the beefed up anchorages and enhanced suspension systems would lower the vehicle’s center-of-gravity, thereby reducing its rollover propensity. Of course, this feat could be far more inexpensively accomplished, and without any of the downsides noted, simply by attaching a few dozen cinderblocks to the bottom of the luggage compartments.

Finally, as noted in Part 5 of this series, a vehicle’s floor structure tends to deteriorate over time (especially in damp climates) – a particular problem where anchorages are not tied into frame members (just as many seat legs are not on many motorcoaches). Particularly with body-on-chassis vehicles (including motorcoach “conversions”), the floors may buckle as the bodies tend to shift forward on the chassis following a severe frontal or oblique impact. This buckling further accelerates the movement of belted passengers against their seatbelts, and unbelted passengers against the seat backs in front, further straining the anchorages as well as compromising the integrity of the belt system.

 

Worse and Worst

As also noted in Part 5 of this series, another similarly-complex trade-off involves the frequency of each collision orientation. For example, seatbelts are most valuable in rollovers, where ejection is more likely to occur than in any other collision orientation. Yet rollovers are rare. In contrast, as noted above, many data suggest that the most frequent collision orientation is a rear-ender, where seatbelts are virtually worthless. This statistic is likely more valid for commuter/express service, in which motorcoaches are often deployed either in stop-and-go, rush-hour, freeway traffic, or at the other end of the trip, in crowded, downtown areas with fellow vehicles (particularly taxies) weaving in and out of their lanes and often requiring multiple sharp braking reactions. In contrast, head-on or oblique collisions may be more frequent in other motorcoach operating sectors, such as tour or charter service, where most of the travel occurs on open roads (often in lightly-trafficked rural areas) where few stops are involved other than one or a handful at the trip’s origin or origins, and where the drivers are on duty for a considerable number of hours. Regardless, as a general principal, those collision orientations in which seat belts provide the most benefits occur least often, while those collision orientations where seat belts provide the least value occur most often.

 

Given such a range and diversity of trade-offs, it is absolutely impossible to claim that even three-point seatbelts are clearly beneficial to passenger on large buses or coaches. The trade-offs are not only enormous, but involve an almost dizzying degree of complexity. When only lap belts are involved, or when the separate shoulder belt sections of certain types of three-point belt configurations are not employed, the use of lap belts on large vehicles is profoundly dangerous. Further, other than in rare rollovers and their even more rare ejections, or collisions with large vehicles or other large objects, three-point seatbelts are of limited value on vehicles with the mass of a full-size bus or coach largely because, during the vast majority of their collisions, they pretty much swat away most objects in their path.

 

Finally, the more the vehicle costs as a result of installing seatbelt technology – including reinforced, heavier seats, significantly stronger anchorages and beefed up suspension systems – the more it also costs to carry around all this extra weight for 20 or more years, or the fewer seats the vehicle could contain to offset this considerable increase in weight. As a consequence, fewer motorcoaches would be affordable and available. Because travel by motorcoach is exponentially safer than travel by any other mode (other than aircraft or passenger rail), the reduction in the number of motorcoaches available will effectively doom other would-be motorcoach passengers to travel in other far-less-safe modes. It is not for no reason that 44 of our 50 States have refused to mandate the installation of any form of seatbelts on their full-size school buses, and why NHTSA has continually refused to endorse their installation on them. By now, NBT readers who have reviewed the last three installments of this series should understand why. 

Publications: National Bus Trader.