CHILD CAR RESTRAINTS
Convenience and Safety ‑ at odds, as usual
Of all the things that I at Consumers Union this is the one that means the most. I was able to get the makers of Child Restraint Devices (CRD) for cars to decide voluntarily to make their CRDs safer. I and the mighty reputation of CONSUMER REPORTS magazine) also influenced the nationwide CRD-use laws.
BACK GROUND
Some things still give us mixed emotions. It is clear by now that a rear seat lap belt should not be used alone to restrain children or adults during a front-end collision. The strap can cause greater injuries to the abdomen than would have occurred if the user had been unrestrained. Yet, I don't want to tell friends that those belts should not be used. Despite the hazard that could arise under certain crash conditions, we feel that the overall benefits justify the continued use of lap belts alone on older vehicles. Should we have condemned the motorized shoulder belt that became popular during the 1980s, because many people failed to use the separate manual lap belt? When Toyota introduced the “Mouse”* belt, the observed seatbelt usage rate was about 10 percent. Since 1981, many people benefited from the shoulder belt and knee restraint bar during a frontal crash.
We face the same quandary when giving advice for safety of children in cars. The National Highway Traffic Safety Administration (NHTSA) publishes what is an unending stream of equipment recalls of Child Restraint Devices (CRD). In the summary book for recalls during 1991 [DOT HS 807 836], they list fourteen recalls, involving six manufacturers. The defects range from inadequate instructions to substandard crash performance.
THE FIRST CRDS WERE WORSE THAN NOTHING
Years ago children who rode in cars were placed in dangerously inadequate car seats secured only by tubular metal hooks that slipped over the back of the front seat. The typical CRD consisted of lightweight tubing. A lightly padded tubular loop or tray crossed in front of the seated child. At most, a light plastic or fabric lap strap kept the child from climbing out. During hard braking or a crash, a car seat would throw the child from the seat into the windshield or instrument panel when the seatback hooks straightened out and the framework collapsed. The makers designed the devices mainly to keep the child out of the mother's way when she was driving.
THE PIONEERING CRASH SIMULATION TESTS
The generally excellent quality of CRDs today is partially due to the pioneering work done by CONSUMERS UNION, publisher of the magazine CONSUMER REPORTS.
A test report published in August 1972 created a sensation because it revealed the weaknesses of current child seats by subjecting each of several CRDs to artificial crashes when belted onto a seat on a crash simulator "sled." This report was "bad news" for the industry. We judged only five of the CRDs acceptable. Of these, the only one rated good was General Motors Infant Carrier, a bucket‑like device to secure a small infant in a semi‑reclined rear‑facing position. The two that were rated fair‑to‑good were the Ford Tot Guard from which kids could easily escape because it had no harness of straps. The other was the Sears Child Safety Harness, which was difficult to install and use. The remaining products were rated poor or NOT ACCEPTABLE.
Representatives of several CRD manufacturers visited CONSUMERS UNION to discuss the "unfairness" of the report. After seeing the violence in the films of our simulated crashes, they went home to redesign their products to withstand the forces revealed in dynamic tests. No one had to make rules to require them to do that.
PROGRESS CAME QUICKLY
The second report on CRDs in the February 1974 issue of CONSUMER REPORTS was more encouraging. This report discussed advantages and disadvantages only with regard to crash test performance. In that report, the GM Love Seat was top rated. The car lap belt was used to pull a one‑piece plastic chair‑like shell back against the car seat back. A strap tied the top rear of the seat to an anchor plate bolted to the rear package shelf of a sedan‑type automobile. This design recommended use of that CRD only on the rear car seat. The Love Seat was not, however, a good choice for those who planned to use the CRD on the rear seat of a station wagon or a hatchback automobile. The Love Seat required installation of the tether anchor plate on the horizontal shelf behind the seat. This installation was difficult for many.
Critics of Consumer Reports described the five-point harness and the top tether as inconvenient. They claimed these were so inconvenient that many parents did not use them properly. Other researchers studied the actual use and misuse of CRDs in the field. They reported that few users took the trouble to fasten the top tether that was required of tall CRDs. This nullified the safety benefits. Without the strap in the back, the top-rated tall CRD is more likely to tip over when the car is stopping or turning. Our critics preferred models that did not depend upon this awkward installation. Those were the fair‑to‑poor rated models that sat low on the seat but were secured using only the car lap belt.
The tall child-chair type CRDs used a five-point harness combines a lap belt (two points) with a vertical strap over each shoulder and a fifth belt through the crotch that keeps the lap belt from pulling up during the crash. Many parents failed to secure the child into the CRD properly. At first, Consumers Union ignored these findings and continued to base its ratings on crash test performance alone.
An editorial in the February 1974 issue, titled "WHERE IS UNCLE SAM?” criticized the NHTSA for not amending the FMVSS 213 (Child Car Restraints) to replace the then‑standard easy‑to‑pass static‑pull laboratory test with the more realistic dynamic sled crash test simulation as pioneered by CU. The static‑pull test consisted of strapping the child‑simulator (a wooden block with a resemblance to a child's torso) into a CRD seat and pulling on the block with a slowly‑applied force of one thousand pounds. This was not a realistic approximation of a real crash. The editorial recommended that the NHTSA adopt the CONSUMERS UNION crash test procedure for evaluating the performance of CRDs in frontal and side crashes. Some members of the Juvenile Product Manufacturers Association were enthusiastic about having FMVSS 213 amended, because it would remove non-complying low‑cost competitors from the market. The cheapest tube‑and‑canvas CRDs cost about 15 dollars. Forty dollars was a more typical price for models that met the requirements of dynamic testing.
“INFANT CARRIERS AND CHILD RESTRAINTS” a March 1975 report, listed advantages and disadvantages of bucket-like devices to carry small infants in or out of an automobile. These are separate from chair‑type restraints for older children. They could convert some CRDs, by arranging some components, to serve as an infant carrier at first. Parents reclined and lowered the infant carrier CRD, and belted it to the seat facing the rear. Then, after the child grew, the CRD became a forward-facing child car restraint. Convertibility became a selling feature to overcome objections to the high price of a dynamically tested CRD. After the child grew, the framework could be flipped around to face forward and placed on the rear seat as recommended. That would position the chair higher and more erect. If the particular CRD seat was tall, so that the child could easily see out the windows of the car, it was necessary to restrain the seat from tipping forward with a separate top tether strap. Sixteen models out of 21 units tested for that report were acceptable. The top‑rated CRD was convertible for use as an infant carrier. It did well in the sled simulated crash tests. When used as a child restraint, it required the use of a five‑point harness and a tether strap. Nevertheless, CONSUMER REPORTS did not describe this one as inconvenient.
A 1975 editorial, "TOO MUCH, TOO LATE," complained that the NHTSA proposal for a dynamic‑test FMVSS 213 amendment was so tough that the industry would fight it, rather than wholeheartedly comply. The NHTSA had finally taken up the challenge presented by the reports from CONSUMERS UNION. NHTSA set performance requirements so stiff that they would force low‑volume CRD makers out of the market. However, the FMVSS 213 rule, as finally adopted, was no longer "too much." They badly watered down the sled test requirements. They deleted the requirements to protect the child when the automobile seat was subject to side impact. They increased the allowable dummy forward motion considerably beyond the criterion recommended by CONSUMER REPORTS, thus exposing the child to danger of striking the front interior of the car or the back of the front seat.
WE EMPHASIZED SAFETY INSTEAD OF COMFORT AND CONVENIENCE
A June 1977 report continued to focus on crash test performance and declined to put as much stress on comfort and convenience of usage. The five top‑rated CRDs all required the use of a top tether strap and they provided a secure environment in front and side impact situations. Twelve CRDs were rated acceptable, two were not. CONSUMERS UNION received many letters from individuals and child‑safety organizations saying that its emphasis on crash test performance alone was a disservice. Well‑meaning parents bought the top‑rated CRDs; then found them to be difficult to install or use properly. If the tethered CRD was used without the child's harness fastened, or with the tether not fastened, the child was probably worse off than if they had belted him into the back seat. If the tethered CRD was placed on the front seat and tied onto a rear seat lap belt, two seat positions were taken. By this time, most cars were being built smaller and seating space was at a premium.
In April 1978 a "QUESTION AND ANSWER" they printed dialogue. This was CONSUMER REPORTS' published reply to the readers who wrote concerning the June 1977 report. Most of the questions related to comfort and convenience. Again, it was plain that the majority rejected the CRD that required the use of the tether. The nature of the answers was that CONSUMERS UNION finally agreed that a good CRD was one that they installed correctly.
FINALLY, THEY REACH A CONSENSUS
In the April 1982 annual Auto Issue of CONSUMER REPORTS the fifth report contained no crash test performance data. Another researcher produced the report on the comfort and convenience factors of CRDs then on the market. For years she had been observing the actual usage patterns of parents in the real world. She recommended a dual‑use convertible CRD for use with infants and older children. The report also mentioned that the adoption of child restraint use laws was progressing. CONSUMERS UNION had long supported this legislative effort, so that non-use would not waste the availability of good CRDs, as often happens with automobile lap and shoulder belts for adults. What to look for now
Like the writer of the report in the January 1992 CONSUMER REPORTS, I assumed that FMVSS 213 impact simulator testing has weeded out the really bad performers when I make these personal judgments on what is an acceptable CRD.
Look for:
Choose a CRD that sits low on the car seat so that it does not require a top tether. This makes the CRD more convenient for transferring from car to car. The child may fuss a while because he can't see out, but he'll get over it.
One that has a well‑padded semi‑rigid shield shaped like a round‑cornered "T" that is placed in front of the child. It will restrain a child's chest and lower torso by distributing the force over a large area, like an airbag permanently inflated. This kind can integrate a hinged shield with the vertical shoulder straps. See figure 2. It is best if they also hinge the shield to swing up out of the way or otherwise secured to the seat so they can’t mislay it. The crotch strap between the child’s legs usually holds down the shield. This strap also prevents the slouching child from submarining under the shield.
The harness must consist of vertical straps on either side of the child's neck. They must closely space them to closely restrain the child's narrow sloping shoulders. Use the tie-bar to keep the straps close together. The harness always restrains the child even during a roll‑over.
The release push button should be easy to recognize by someone attempting to remove the child following an accident. Operating it should be simple. The button ought to be inaccessible to the seated child. After a crash, someone must be able to get the child out quickly so the push button should be visible at the front edge of the seat.
The federal standard requires that the push button force be high, even if the button is inaccessible. I think that means they don’t trust us.
The force required to push the latch plate into the buckle should not be so high that you get the false sensation that it is latched because the latch plate sticks. If the latch plate can be pushed in part way and held by friction, that is a false-latch situation.
You should be able to fasten the harness and shield with only one hand. One end of the latching mechanism should be supported so that you can conveniently secure the child while leaning into the back seat of a two‑door car. Some CRDs seem to require three hands to secure the child.
If you choose a booster seat for the child that has outgrown the "baby seat, select one that does more than just raise the child up from the car seat. Raising the child improves the comfort of the knees and allows the child to see out better. However, the adult lap (and rear seat shoulder belt, if available) is not as good as a force-distributing shield secured by the car lap belt.
Please remember the value of adequate restraint for the parents and for the children. A little inconvenience, when "buckling up" can prevent a lifetime of pain and suffering for an innocent child.
I was Auto Safety Engineer for Consumers Union 1972‑1981. The original version of this is dated February 9,1992. The illustrations were copied from pages of the catalog from Service Merchandise of Nashville, TN. I finally decide that those illustrations are way out-of-date.
* The motorized shoulder belt was nick named the “Mouse belt” because the upper anchor was located at the top of the car’s B-pillar when the belt was in use. When the passenger opened the door a hidden motor moved the anchor up the B pillar and forward above the door opening to stop near the windshield.
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