TESTIMONIES

NHTSA has not been alone in the promotion of compartmentalization to a believing public. The following excerpts are a sampling of the inaccurate material that has been circulated by NHTSA and all segments of the school bus establishment.

From the report of Hearings before the Subcommittee on Oversight and Investigations of the Committee on Interstate and Foreign Commerce, U.S. House of Representatives testimony submitted by the National Highway Traffic Safety Administration dated February 27, 1976 (Serial No.94-83):

• Interior protection for occupants is provided for in Standard No 222, School Bus Passenger Seating and Crash Protection. This standard relies on compartmentalization through the use of well padded and well constructed seats to provide occupant protection on school buses.

• A more recent study, consisting of static and dynamic testing by A.M.F. Corporation of prototype seats designed to meet the proposed requirements of the standard, was found by NHTSA to be more persuasive than the (earlier) UCLA study. The data generated by the AMF study support the position that sufficient compartmentalization of occupants would be provided (by the proposed seat).

Engineers who performed testing of the new seat after implementation of the seating at East Liberty, Ohio were more guarded in their evaluation. The sled tested the new seats with and without seat belts and for frontal impacts only. (School Bus Passenger Seat and Lap Belt Sled Tests, December 1978, DOT HS-804 985). They concluded:

• 3.3 Compartmentalization. The term "compartmentalization" is used in this study in reference to the ability of a seat structure to contain an occupant during and following an impact. This containment is visualized as the extent to which the dummy remains within a specified volume during and following impact. The term containment is defined, in this study, as the percentage of the victim's body remaining within volume during impact and rebound.

• 4.1.4 Compartmentalization evaluation. The data shows that in general a belted dummy receives more containment than an unbelted dummy both during impact and rebound.

In 1985 NHTSA issued a report called Safety Belts In School Buses (DOT HS 806 799). Their thinking was unchanged:

• Federal Motor Vehicle Safety Standard (FMVSS) 222, "School Bus Passenger Seating and Crash Protection," sets requirements for the interior of large school buses which provide children a high level of protection without the need to "buckle up." The standard requires high and strong seats and seat backs, seat back padding, and seat spacing that reduces the chance of the occupant being thrown over the seat in front. The approach taken to bus safety is commonly referred to as compartmentalization.

• Compartmentalization, as outlined in the standard, requires strength in the entire seating system which includes the floor, the seat frame and the fastening of the frames to the floor while at the same time providing seat system padding and flexibility to absorb energy in a crash.

• NHTSA believes that the occupant protection required in school buses manufactured after April I, 1977, plus the inherent safety of a highly recognizable vehicle that travels on a regular route, provides a high level of safety protection.

And, as posted on the internet, NHTSA continues to adhere to their quarter century old supposition:

• Rather than requiring seat belts, NHTSA decided that the best way to provide crash protection to passengers is through a concept called "compartmentalization." This requires that the interior of large buses provide occupant protection so that children are protected without the need to buckle-up. Occupant crash protection is provided by a protective envelope consisting of strong, closely-spaced seats that have energy-absorbing seat backs. The effectiveness of compartmentalization has been confirmed in the NTSB and NAS studies.  

• NHTSA Web Site http://www.nhtsa.dot.gov/people/injury/buses/pub/seatbelt.hmp.html

NHTSA's confidence in compartmentalization is echoed by the school bus industry. In the fall of 1983 the Pennsylvania School Bus Association wrote:

• NHTSA agrees that children should be protected on school buses BUT they do not. support a requirement for seat belts for passengers in large school buses. Improving the seating compartments eliminates the need for seat belts and provides sufficient crash protection, according to NHTSA.

• Persons in tile pupil transportation industry sincerely care what happens to students transported by school buses. Students, school bus drivers, and other knowledgeable persons involved with the daily operation of school buses also fully comprehend the problems of seat belts on school buses. Seats in today's school buses have higher, fully padded seat backs to provide passenger “compartmentalization” which is preferred to the installation of seat belts as a reasonable passenger protection method.

In the February/March 1984 issue of School Bus Fleet C. Morris Adams, then Vice President of school bus manufacturer, Thomas Built Buses chimed in:

• Being mandated today by regulations through the U.S. Department of Transportation are compartmentalization type seating arrangements. This is what the federal government, through their testing and research, came up with in lieu of seat belts.

• If we pad the hostile environment of the bus, mainly the seat frames, and make the seat frames so they will absorb a certain amount of energy rather than the kids' body having to absorb it, say in a rear end accident where the kid is thrown backward, or a front end or side accident where it's thrown forward, if those seats will flex a certain amount they can absorb a tremendous amount of energy, which keeps it out of the child's body.

The web site of the National School Transportation Association (NSTA) joins the chorus of official support form compartmentalization. In a statement adopted by the NSTA Board of Directors in 1984:

• This is why NSTA supports the National Highway Traffic Safety Administration's position on occupant protection in school buses.

• Our association is not so much opposed to the use of safety belts in school buses as it is supportive of the concept of compartmentalization. We came to this position after years of tests, experiments and studies resulted in the NHTSA concluding that compartmentalization provides an adequate level of safety protection. In contrast, there are no standards established for seat belts on large school buses.

• NSTA believes that compartmentalization -containing children within a structurally reinforced passenger compartment of fully padded, high-back seats and crash barriers is preferable to any form of containment that relies upon the use of safety belts or other similar restraining devices.

• Furthermore, we believe that the studies and excellent safety record of school buses support compartmentalization. http://www.stnonline.com/sb_nsta.htm

In March of 1985, the Maryland State Department of Education developed a booklet addressed to "Persons Interested in Pupil Transportation Safety" in which they inform all that might question pupil passenger protection on school buses:

• The school bus is designed, engineered, and constructed with a passive restraint system as an integral part of the vehicle. This system, compartmentalization--also known as the "egg carton concept"-- protects the school bus passengers at crucial times without any effort on their part. The most vital component of this system is the school bus seat. The seats in today's school buses are situated closer together and have higher, fully padded backs which provide for the compartmentalization and improved safety of each pupil transported. In the case of the front seat, a fully padded front barrier extending the full width of the seat serves the same purpose.

In the Letters to the Editor of the industry publication, School Bus Fleet, a 1994 sample letter was printed with the suggestion that the letter could be used as a model for others when replying to questions about seat belts on school buses. David Huff, Montana's Director of Pupil Transportation wrote:

• There is another way that school buses use, it is called compartmentalization." That's a real big word that means that the seating area of a school bus is built with specially padded high-back seats. These padded high-back seats protect people in school buses during accidents.

• The good thing about "compartmentalization" is that kids don't have to do anything to be protected except sit down in the seat. The reason that is good is because not all kids think about safety like you do, and some don't like to use seat belts. But with "compartmentalization," all kids get protection, not just those who are smart enough to put the seat belt on properly every time. Continuing school bus establishment barrage of pro compartmentalization information, in 1997 the Pupil Transportation Unit of the Florida Department of Education wrote:

• All school buses built since April 1, 1977 have a passive safety feature called "compartmentalization" that provides protection to students equal to or greater than seat belts. Federal Motor Vehicle Safety Standard 222, School Bus Passenger Seating and Crash Protection, provides this level of safety by requiring seats to be mounted close together with high backs and padding. 

• It also specifies anchorage strength and deflection criteria that require seats to bend and absorb crash forces without breaking or coming loose from the floor. The best demonstration of this concept is to get on a modern school bus and witness the egg carton like "compartmentalized" environment that students ride in.

• Recent studies by the National Research Council and the Center for Urban Transportation Research at the University of South Florida have confirmed the high level of safety provided by compartmentalization and the other safety equipment on school buses.

In a position paper revised and updated in January of 1999, the powerful National Association of State Directors of Pupil Transportation reiterated their negative position:

• The inherent benefits of a "passive" crash protection system versus an "active" crash protection system are important. First, the benefits of a "passive" system are always there, and require no action by the vehicle occupant. Second, "passive" crash protection systems, particularly those that utilize energy absorbing structures and padding, provide protection to different sizes of occupants and in various seating positions. The "compartmentalization" concept for passenger crash protection in school buses is a passive crash protection.

School Transportation News, the influential school bus industry publication explains:

• The concept of compartmentalization envisions children riding in a cocoon or compartment surrounded by an energy-absorbing, passive occupant protection system. Some industry experts use the metaphor "egg carton" as in cushioning the eggs inside, to describe compartmentalization.

NHTSA School Bus Crashworthiness Research Report April 2002

• This impressive safety record is a result of the Department of Transportation's requirements for compartmentalization on large school buses, and lap belts plus compartmentalization on small school buses. Moreover, the protective abilities of today's school buses have been reaffirmed by two years of research.

Nowhere in this research of industry representations over the past 2 ½  decades is there any reference to the incomplete compartmentalization of school bus seats and the dangers to the children inherent in the inadequacy of school bus seats during side impact and rollover crashes.

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