Reducing Risks to Children in Vehicles With Passenger

Reducing Risks to Children in Vehicles With Passenger
Reducing Risks to Children in Vehicles With Passenger Airbags
John D. Graham, PhD; Sue J. Goldie, MD, MPH; Maria Segui-Gomez, MD, MPH;
Kimberly M. Thompson, ScD; Toben Nelson, MS; Roberta Glass, MS; Ashley Simpson, BA; and
Leo G. Woerner, MS
ABSTRACT. This review examines the risk that passenger airbags pose for children and discusses behavioral and technologic measures aimed at protecting children from airbag deployment. Although airbags reduce
fatal crash injuries among adult drivers and passengers,
this safety technology increases mortality risk among
children younger than age 12. The magnitude of the risk
is multiplied when children are unrestrained or restrained improperly. As new vehicles are resold to buyers
who tend to be less safety-conscious than new car owners, the number of children endangered by passenger
airbag deployment may increase.
For vehicles already in the fleet, strong measures are
required to secure children in the rear seat and increase
the proper use of appropriate restraint systems through
police enforcement of laws. One promising strategy is to
amend child passenger safety laws to require that parents
secure children in the rear seats. For future vehicles, a
mandatory performance standard should be adopted that
suppresses airbag deployment automatically if a child is
located in the front passenger seat. Other promising improvements in airbag design also are discussed. Major
changes in passenger airbag design must be evaluated in
a broad analytical framework that considers the welfare
of adults as well as children. Pediatrics 1998;102(1). URL:
http://www.pediatrics.org/cgi/content/full/102/1/e3; airbags, risk-benefit ratios, injury, restraint systems.
ABBREVIATION. NHTSA, National Highway Traffic Safety Administration.
M
anufacturers of passenger cars and light
trucks selling in the US market are now
required to equip new vehicles with a passenger-side airbag as well as a driver-side airbag.
This regulatory impetus has caused .60 million vehicles to be equipped with airbags in the United
States from 1989 to 1997, half of them with driveronly airbag systems, the other half with dual systems
that include a passenger-side airbag.1 Even without
legal requirements, the driver-side airbag has become widely available throughout the developed
world. The passenger-side airbag also is beginning to
penetrate new vehicle markets in Europe, Australia,
and parts of Asia, but it is much less common.2,3
Real-world crash data indicate that US airbag deFrom the Harvard Center for Risk Analysis, Boston, Massachusetts.
Received for publication Jan 2, 1998; accepted Feb 20, 1998.
Reprint requests to (J.D.G.) Harvard Center for Risk Analysis, 718 Huntington Ave, Boston, MA 02115.
PEDIATRICS (ISSN 0031 4005). Copyright © 1998 by the American Academy of Pediatrics.
http://www.pediatrics.org/cgi/content/full/102/1/e3
signs are reducing driver and adult passenger fatalities by ;10% to 15%, averaged over all crash types,
with maximum effectiveness in frontal crashes.4,5
When all vehicles in the United States are equipped
with dual frontal airbag systems, ;3000 lives are
projected to be saved annually among adults—
;2300 drivers and 700 adult passengers.6,7 Although
the observed rate of airbag effectiveness is about
two-thirds less than it was predicted 10 to 20 years
ago,8 –10 driver airbag technology appears to have
cost-effectiveness ratios that are comparable to many
well-accepted medical and public health interventions. The cost-effectiveness ratio for the passengerside airbag is closer to the high end of the range of
acceptable investments.11
Hidden in the overall cost-effectiveness figures are
serious adverse consequences for children who are
now less safe because of passenger-side airbags.
Children are the only subgroup of the population
that is known to have experienced a net increase in
risk of death attributable to the installation of airbags.4,12,13 In this article, the risks of airbags to children are assessed and various strategies for reducing
the risk to children are reviewed. We focus on children younger than age 12 because crash data (which
lack information on the weight or height of the injured children) indicate that they are the children
most at risk.4
RISKS TO CHILDREN
Children are being killed and seriously injured by
passenger-side airbags in relatively low-speed
crashes that typically would not have proven fatal.14 –16 As of late 1997, the National Highway Traffic
Safety Administration (NHTSA) had identified 52
passengers who, in the judgment of postcrash investigators, were fatally injured by passenger-side airbags. Forty-nine of these passengers were children
younger than age 12. Twelve were infants in rearfacing child restraints; 34 were unrestrained; and 3
were restrained by at least the lap belt. Another 20
incidents are now under investigation, and many of
these are likely to be classified as airbag-induced
fatalities.6 Postcrash investigations have not determined how many additional children have been
harmed (but not killed) by airbags in higher-speed
crashes.
Two scenarios appear to account for the childhood
fatalities caused by deployment of passenger-side
airbags.1 First, when infants are seated in rear-facing
infant restraints in the front seat, the head and neck
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are in close proximity to the airbag housing; fatal
head and neck injuries result from the force of the
rapidly inflating airbag against the child safety seat.
Second, unrestrained or improperly restrained children who are forward-facing may be seated too close
to the airbag housing or may be thrown forward
during precrash braking, causing the head and neck
to be placed in the deployment zone of the rapidly
inflating bag. In addition, several restrained children
have been killed or seriously injured by passengerside airbags; the circumstances surrounding some of
these incidents are uncertain, but the mechanisms of
death are the same.14
Airbags may have saved the lives of some restrained children. If such cases exist, they will not be
identifiable on a case-by-case basis because the protective effects of the safety belt or child restraint are
difficult to distinguish from the protective effects of
the airbag. Yet it is feasible to determine statistically
whether the net impact of passenger-side airbags on
child mortality—lives saved versus lives lost— has
been positive or negative.4,17
In Tables 1 and 2, we present updated estimates of
the net mortality risk to children from passenger-side
airbags using US crash fatality data for 1990 –1996
and the analytic method of double-paired comparison.18 The ratio of child passenger deaths to driver
deaths is computed for those fatal crashes in which
both a child and driver were occupying the front
seat. The ratio for vehicles with passenger-side airbags is compared with the ratio for vehicles with
driver-only airbags and to vehicles with manual belts
only. If passenger-side airbags save more lives of
children than they kill, then the ratios for vehicles
with passenger-side airbags should be less than the
ratios for vehicles without passenger-side airbags.
The presence of a passenger-side airbag in a vehicle
is associated with a net 63% increase in child fatality
risk. Furthermore, the data suggest that passengerside airbags are not causing net reductions in fatality
risk among children who were restrained in a child
safety seat or safety belt when the crash occurred.
Overall, any lives of children being saved by passenger-side airbags are being overwhelmed by the subTABLE 1.
Estimates of the Impact of the Passenger Airbag on
Childhood Mortality (Age 0 –12); Fatal Accident Reporting System
1990 –1997 Model Year Vehicles, 1989 –1996 Calendar Years
Controls
Crashes of all directions
Dual bags
Driver-only airbags
Manual belts only
Frontal crashes only
Dual bags
Driver-only airbags
Manual belts only
Child Driver Ratio Risk of Dual
Deaths Deaths
Relative to
Controls
102
151
299
77
186
343
1.32
0.81
0.87
—
1.63*
1.52*
71
95
203
42
103
211
1.69
0.92
0.96
—
1.84*
1.76**
* P , .05; ** P , .01.
Note: The unrestrained category includes those children known to
be unrestrained or restrained improperly. Data obtained from the
Fatal Accident Reporting System, NHTSA. Includes only those
fatal crashes where both a driver and child passenger were located
in the front seat.
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TABLE 2.
Child/Driver Death Ratios by Child Restraint
Use—All Crashes
Controls
Dual bags
Driver-only
airbags
Manual belts
only
Unrestrained
Risk of Restrained Risk of
Dual
Dual
Relative to
Relative to
Control
Controls
2.30
1.09
—
2.11*
0.82
0.67
—
1.22
0.94
2.45**
0.79
1.04
* P , .05; ** P , .01.
Note: The unrestrained category includes those children known to
be unrestrained or restrained improperly. Data obtained from the
Fatal Accident Reporting System, NHTSA. Includes only those
fatal crashes where both a driver and child passenger were located
in the front seat.
stantial number of children killed by passenger-side
airbags.
A recent regulatory analysis estimated that unless
additional countermeasures are implemented, an additional 100 children younger than age 12 will be
killed each year in the United States when all vehicles are equipped with passenger-side airbags.1,7 This
estimate may be too optimistic because more young
children will be placed at risk as current vehicles
with passenger-side airbags are resold over the next
20 years to less safety-conscious buyers who may
have larger families and may place improperly restrained children in the front seats more frequently.
It has been suggested that among those airbag
designs now in use, some passenger-side airbags are
less safe than others.19,20 Insufficient real-world data
are available to evaluate that assertion, in part because information on the design parameters of airbag
systems is not available publicly. The federal government is considering a new policy that will require
manufacturers to furnish selected information about
airbag designs to the government.
Overall, the benefit-risk ratio for passenger-side
airbags is far worse than it is for driver-side airbags.
For each child that has been fatally injured by airbags, the lives of 5 to 10 adult passengers have been
saved.7,17 The ratio of lives saved to lives lost for the
driver-side airbag is ;75 to 1.7 If life expectancy (or
years of life) is used as the metric for evaluation
(rather than lives saved), the benefit-to-risk ratio is
no better than 5 to 1 for the passenger-side airbag.11
We are aware of no mandatory measure in the history of preventive medicine that has been preserved
with a benefit-risk ratio so close to 1 to 1, although
the ratio for the passenger-side airbag may improve
in the future, for reasons discussed below.
Even if the current ratio of benefit to risk were
judged to be acceptable on grounds of economic
efficiency, there are ethical problems with allowing
or mandating children to face fatal consequences to
make adults safer. A reduction in risk also may be
necessary to sustain public confidence in airbag technology, the airbag regulation, and the public and
private institutions that have brought this device to
the marketplace.21–23
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STRATEGIES TO REDUCE RISK
The objective of any strategy should be to eliminate, or at least to reduce significantly, the risks to
children through measures that do not compromise
airbag effectiveness for adults. Below, we discuss
five strategies that should have broad applicability
throughout the world.
Children Should Be Restrained Properly
Tremendous resources have been devoted to increasing child restraint and belt use over the past 20
years.24 Rates of child restraint use in the United
States have risen from 20% in 1980 to 79% in 1996.25,26
The most recent data found that 93% of infants, 75%
of toddlers, and 65% of subteens were restrained,26
although this study did not measure the extent of
misuse. Currently, approximately half of the deaths
among infants and toddlers in the United States annually occur in crashes in which children are not
restrained in child restraint devices.24 Children from
less educated, low-income, and minority families are
less likely than other children to use child restraints
and safety belts.27
Misuse of child restraint devices is a widespread
problem, observed in as many as 80% of the children
restrained in child safety seats.28 –32 Proper restraint
refers here to the use of age- and weight-adequate
restraint systems, the adequate restraint of the child
to the system, and the adequate restraint of the child
seat or booster to the vehicle seat.
Proper restraint use reduces a child’s chances of
being killed or seriously injured in a motor vehicle
crash, even in vehicles without passenger-side airbags. Even accounting for misuse, the magnitude of
the protective effect is substantial, probably greater
than the 45% reduction in fatality risk attributed to
adult use of lap and shoulder belts.24,33–35 Proper child
restraint use also dramatically reduces a child’s risk
of being killed or seriously injured by a passengerside airbag (except if the child is in a rear-facing child
seat). A properly restrained forward-facing child, positioned with the seat back as far as possible, has a
minimal risk of death or serious injury from deployment of passenger-side airbags.1
The most promising strategy for achieving higher
levels of proper restraint use is to replace secondary
with primary enforcement laws, thereby permitting police officers to apprehend and fine drivers who allows
occupants to ride in their vehicle unrestrained. Unrestrained drivers are particularly likely to allow their
children to ride unrestrained in the front seat.36,37 Thus,
efforts to increase adult restraint use, which remains
,65% in the United States,26 may induce increased
child restraint use. Controlled studies have demonstrated that highly visible educational and enforcement
efforts can increase the rate of adult and child restraint
use in a community.38 – 40 In the future, more uniform
and improved designs of child restraint systems (eg,
uniform seat mountings and top tether requirements)
should reduce misuse and facilitate compliance with
child passenger safety laws.
Although efforts to increase the rate of proper
child restraint should be a major priority, this strat-
egy alone is unlikely to be completely successful in
protecting children from passenger-side airbags. Additional increases in child restraint use will come
slowly. The residual unrestrained child population
in the United States will be difficult to reach without
substantial and well-targeted resources. Moreover,
the widespread problem of misuse is more complicated to solve through education and is difficult for
police to detect. The fact that several restrained children have been killed and seriously injured by passenger-side airbags cautions us against complete dependence on child restraint use and safety belts as
measures to protect children from the dangers posed
by passenger-side airbags.35
Secure Children in the Rear Seat
Approximately one third of US children younger
than age 12 traveling in motor vehicles are seated in
the front seat.36,41,42 The front-seating position is used
more frequently by infants and toddlers than by
young children and subteens. In the 1996 Controlled
Intersection Study, 71% of infants and 67% of toddlers were observed riding in the front seat (NCSA,
NHTSA, personal communication). However, these
estimates may be upwards, and the percentage of
infants and toddlers in the front seat has been declining gradually for 10 years.41
It is feasible to move large numbers of children
from the front seat to the rear seat. In continental
European nations, such as Germany, France, and
Belgium, traffic laws prohibiting children from
riding in the front were enforced from the mid-1970s
to the early 1990s, well before the introduction of
passenger-side airbags in Europe. In recent years,
these laws have been relaxed following guidance
from the European Commission.42 Yet, it is still customary in many European countries for children to
ride in the rear of the vehicle, even if the vehicle has
only two occupants (a driver and a child). A recent
roadside survey of vehicles occupied by at least one
child in Frankfurt, Brussels, and Paris found ,15% of
such vehicles with a child in the front seat.43 Even in
the United States, where no such laws (until very
recently) have existed, some states have twice the
proportion of children riding in the front seat as
other states.41
It is well established that the rear seat is intrinsically safer than the front seat for an occupant of any
age.44,45 In the absence of a passenger-side airbag, a
child’s average risk of fatality is 20% to 40% lower in
the rear compared with the front seat.13,35 The risk of
injury also is diminished in the rear seat.34,45,46 If a
passenger-side airbag is present in the vehicle, the
net safety advantage of the rear seat for children is
enlarged, for both restrained and unrestrained children.13
The NHTSA recommended recently that states
amend child passenger safety laws to require that
children sit in the rear when a seat is available.47
Rhode Island became the first state to enact such a
law, albeit only for children younger than age six.
Several states are now considering similar legislation.48 Recent surveys have found that a large major-
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ity of parents (including those with young children)
have favorable attitudes toward the idea of requiring
children to sit in the rear.22 Reticence about new
legislation in this area appears to revolve around
three concerns discussed below.
First, parents with large families and car-pooling
arrangements may have no choice but to allow one
or more children to ride in the front seat. However,
shortage of rear seating capacity is rarely a valid
explanation for children riding in the front. Of the
17 000 fatal crashes involving US children seated in
the front from 1985–1996, empty seats in the rear
were available in .95% of the vehicles and, in 65% of
the vehicles, the rear seat was completely unoccupied.41 However, any laws on this matter should
apply only to vehicles that have a rear seat and only
in circumstances in which the rear seat is otherwise
unoccupied.
Second, some older vehicles are equipped with
only a lap belt in the rear seat; thus, it may seem safer
to seat the child in the front, where both a shoulder
belt and a lap belt are always available. The available
data on this issue are limited. It may be appropriate
to restrict the applicability of child seating laws to
the vast majority of vehicles on the road in the
United States that are equipped with lap and shoulder belts in the outboard rear seating positions. At a
minimum, such laws should apply to any vehicle
that is equipped with a passenger-side airbag, because all such vehicles also are equipped with lap/
shoulder belts in outboard front and rear positions.
Third, to legislate where parents must seat their
children in a vehicle may be viewed as an excessive
intrusion on the part of government into the realm of
parental choice. However, similar objections could
be made against the existing child passenger safety
laws that compel parents to purchase child restraint
devices and use these devices in specified ways.
Child seating laws would seem to have at least as
much philosophical justification—rooted in the
state’s interest in protecting the rights and welfare of
children—as child restraint use laws.
As additional resources are devoted to enforcing
adult and child passenger safety laws in the states, it
may be appropriate to coordinate such efforts with
amendments to such laws that compel children to
ride in the rear seat. Police officers will find it easier
to observe where a child is seated than to observe
whether a restraint is used and used properly. Laws
against improper child seating position will provide
police a clear and indisputable rationale for stopping
a vehicle, thereby making more feasible stringent
enforcement of child and adult restraint use laws.
Once a vehicle is stopped, a police officer can make a
more effective observation of restraint use in each
seating position.
Suppress Airbag Deployment Through Active or
Passive Measures to Protect Children
If significant numbers of children continue to ride
in the front seat, it may become necessary to disarm
passenger-side airbags to protect these children.
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Active Disarmament
The NHTSA now permits dealers and mechanics
to install a manual cutoff switch in passenger car
vehicles with airbags that can be used by owners to
disarm an airbag system temporarily. These switches
already are available in pick-up trucks that do not
have a rear seat. To obtain a cutoff switch, the owner
must make a specific, written request to NHTSA,
demonstrating that he or she falls into one of four
prescribed at-risk groups. One of these groups includes owners who, because of car-pooling or the
child’s medical condition, must have a child in the
front seat.
Offering choice about the operation of airbags to
parents and caregivers is an idea that has met determined resistance in the United States.6 Offering this
choice contradicts the simple message that children
should ride in the rear seat. Car dealers, airbag suppliers, and vehicle manufacturers fear additional liability. Moreover, in vehicles with passenger-side
airbags, the shoulder belt is designed to allow greater
excursion to reduce the risk of belt-related injuries;
disconnecting the airbag leaves the occupant with a
suboptimal shoulder belt system. Some people fear
the potential regret felt by adults who make incorrect
or negligent use of the freedom to arm or disarm
airbags. There also are fears that the power to disarm
and rearm airbags, whether done permanently or on
a trip-by-trip basis, will not be used wisely by consumers. Adults who allow children to ride in the
front seat unrestrained may tend to be the same
adults who are least likely to make sure that the
passenger-side airbag is disarmed for a child or rearmed when an adult passenger needs it. Research is
needed to determine how vehicle owners exercise
the limited freedom to purchase and use manual
cutoff switches.
There is a precedent for the active disarmament
approach in Sweden. In contrast to the US, Sweden is
now making a strong push to promote use of rearfacing restraints in the front seat for both infants and
toddlers. Use of the front seat for children is seen as
a valued convenience for parents, whereas the rearfacing restraint design is considered safer than the
forward-facing design for infants as well as toddlers.
Parents with infants and toddlers are now encouraged by Swedish authorities to disarm their passenger-side airbag systems during the child’s developmental years. When children are old enough,
families are encouraged to have their passenger-side
airbag rearmed.49
Passive Disarmament
Instead of relying exclusively on consumers to
make informed decisions about protecting children
from passenger-side airbags, vehicles can be redesigned to suppress airbag deployment if a child is
seated in the front. For example, some airbag systems sold by Mercedes-Benz already have a weight
sensor on the passenger side that prevents airbag
deployment if no one is occupying the seat. The
original purpose of this capability was to prevent
unnecessary deployments and the corresponding
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costs of system replacement. If the threshold for the
weight sensor were set at some given weight, for
example 80 pounds, it might be feasible to suppress
airbag deployment when the seat is empty or when it
is occupied by a child.
Any technologic solution must be evaluated with
respect to error rates. False-negative errors, that is,
failing to disarm when a child is in the seat, could
occur if the child is holding something (eg, books,
cargo, groceries) or is not sitting properly or is placed
in a tightly grounded child restraint device. Falsepositive errors, that is, cases in which the system
suppresses deployment when an adult is seated in
the front, could arise from nuances in the way the
adult is situated in the seat relative to a weightsensoring mechanism. Some suppliers believe that
proximity sensors will ultimately prove to be more
dependable than weight sensors. The passive disarmament approach to protecting children seems
promising if both types of errors can be minimized at
a reasonable cost.
A potential objection to passive disarmament is
that restrained children should not be deprived of
airbag protection. Although some experimental data
suggest that injuries to restrained children can be
mitigated by airbag deployment, the real-world data
have yet to show overall significant benefit to restrained children.12 If such benefits are proven, it
should be feasible to disarm passenger-side airbags
automatically only if the child in the front is unrestrained, although misuse of restraints will be difficult to detect, even by a smart airbag.
Passive disarmament should be mandated by the
government directly or indirectly through a performance standard aimed at reducing risk to children.
The American Association of Automobile Manufacturers already has formally requested that the
NHTSA amend the airbag standard to include a compliance test involving an out-of-position child dummy,50 and the risk of future liability claims may induce some manufacturers to voluntarily install
airbag suppression systems that protect unrestrained
children.51
Raise Deployment Thresholds for Airbags to Prevent
Unnecessary Firings
When children experience fatal injuries from airbag deployment, the crashes often are relatively lowspeed impacts that would otherwise not have been
fatal.14 This empirical observation led to the suggestion that deployment thresholds for airbags be raised
from their current level of 12 miles per hour into a
fixed barrier, with a range from 7 to 15 mph (or ;11
to 24 km/hour) to a considerably higher level (eg,
near 18 mph or 30 km/hour). A case can be made
that the threshold for firing on the passenger side
should be set even higher than the threshold on the
driver side, because there is no steering wheel on the
passenger side.
Vehicle manufacturers and suppliers are currently
reexamining where airbag deployment thresholds
should be set. This decision is not governed directly
by the NHTSA’s regulations, allowing manufacturers design flexibility in this area.
A potential drawback to raising deployment
thresholds, without improving the performance of
crash sensors, is that airbags will take longer to deploy, particularly in so-called soft crashes (eg, a crash
against a utility pole), where the crash pulses are
attenuated and spread over time. A longer time interval from crash to bag inflation gives more opportunity for adults and children to slide forward into
the airbag’s deployment zone. As sensor performance is improved, either through placement of additional satellite sensors in the front of the vehicle or
through advanced sensor technology, it should be
feasible to raise deployment thresholds without delaying airbag deployment. A complementary solution may be to block airbag deployment if the time
required to trigger inflation exceeds some preset
time, gauged as the time during the crash that an
unrestrained passenger takes to move into the airbag’s deployment zone.
Depower Airbag Systems and/or Install Dual-stage
Inflators Linked to Crash Severity
Manufacturers selling vehicles in Canada and the
United States already have received permission from
regulatory agencies to depower airbags by 20% to
35%.1 Depowering refers to decreasing the energy of
deployment and/or reducing the volume of the bags
themselves. A study in the United States found little
evidence that adult occupants who died in frontal
crashes involving airbags died because their airbags
had insufficient powering.52 Some experimental
models suggest that depowering can reduce significantly the rate and severity of airbag-induced injuries to children and adults.1 In Australia, where rates
of seat belt use exceed 90%, some depowered airbags, which are also small in volume (eg, the Holden
bag), are in use. Early real-world data from Australia
suggest that depowered airbags, in conjunction with
other design features, inflict fewer and less severe
injuries without sacrificing protection in high-speed
crashes.3
Another notable refinement is dual-stage inflation.
Once a collision is sensed and is of low-velocity, a
first reduced charge of propellant is deployed into
the airbag. Milliseconds later, if deceleration associated with what turns to be a more severe collision is
detected, a second charge of propellant is released
that makes the airbag larger and/or firmer. For decades, this approach was considered promising because it would mitigate airbag-induced injuries to
out-of-position children and adults in low-speed
crashes.15,28,53–56 With this design, two deployment
thresholds are required rather than one. An early
version of the dual-stage inflator was used on the
passenger side of 10 000 General Motors cars
equipped with airbags during model years 1974 –
1976.57 An elaboration of dual-stage inflation might
entail allowing only first-stage deployments when a
child is occupying the front passenger seat.
In recent offerings, BMW and Mercedes-Benz
include two different thresholds of deployment
based on whether the occupant is belted.56 A properly belted occupant is less likely to need airbag
protection in relatively low-speed impacts than is an
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unbelted occupant. Despite these innovations, the
BMW owners manual recommends that children
younger than age 12 sit in the rear.58
There exists a formidable barrier to protecting children through use of precise adjustments in the inflation power of airbags. The child dummies currently
used by suppliers, manufacturers, and government
may not provide an accurate indication of the vulnerability of a child’s head, brain, and neck, which
may vary significantly from child to child. The minimum force on the neck necessary to fatally or severely injure a child is not very different from
smaller forces on the neck that would not be associated with significant injury.59 – 61 This narrow window
needs to be defined precisely for children of different
vulnerabilities and reflected in sophisticated child
dummies.
Any child whose head is extremely close to the
airbag when deployment occurs (,1 inch) is likely to
suffer serious or fatal injury as long as the airbag is
powered sufficiently to provide protection for large
adults in a moderate-speed crash. A tradeoff between adult and child passenger protection has been
recognized by airbag engineers for .25 years.62
Dual-stage inflation, coupled with improved sensor
technology and improved child dummies, should
make this trade-off more favorable, but will not eliminate it.
CONCLUSION
The introduction of the passenger-side airbag into
motor vehicles has caused an increased risk of fatality to children occupying the front seat. The precise
magnitude of the increase is unknown, but it is apparent that more lives of children are being lost than
saved because of passenger-side airbags.
A variety of measures can be implemented to reduce the airbag’s risk to children and thereby improve the airbag’s overall of benefit-to-risk ratio. The
fastest to implement and most effective measure entails moving children from the front seat to the rear
seat. In .95% of crash situations when a child is in
front, an unused seat is available in the rear. It also is
critical to make sure that children are restrained
properly, regardless of where in the vehicle they sit.
Increasing the rate of adult restraint use should indirectly induce an increase in the rate of child restraint use, because the behaviors appear to be correlated.36,37
Public education is paving the way for progress on
both proper child seating position and child restraint
use. Yet dramatic and sustained changes in behaviors will require renewed vigor in police enforcement
of child and adult passenger safety laws, including
amendments to existing laws that compel children to
be seated in the rear.
The NHTSA recently authorized an active approach to airbag suppression by permitting at-risk
owners to install a manual cut-off switch. Research is
needed to determine whether the limited freedom
authorized by the new policy is used wisely by vehicle owners.
New technologies based on weight and proximity
sensing are being developed that would suppress
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airbag deployment automatically if a child is seated
in front (or if any passenger is too close to the airbag).
A governmental mandate to protect children with
airbag suppression technologies may be necessary,
because some vehicle manufacturers may see little
commercial value in voluntary design changes
aimed primarily at protecting unrestrained children.
Other improvements in airbag design, such as higher
deployment thresholds, dual deployment thresholds, and depowering of inflators, are being made
and should reduce the number and severity of injuries to adults and children. Dual-stage inflation and
improvements in the performance of sensors will
play an important role in the design of advanced
airbag systems and are likely to penetrate the marketplace in the near future, before regulatory requirements.
Major design changes in the passenger-side airbag
system need to be considered part of a broader analytical framework that includes consideration of possible trade-offs between the welfare of adult and
child passengers. It also should be understood that
most technical improvements will only be feasible
and cost-effective for new vehicles. Behavioral solutions, coupled with education and police enforcement, are essential for protecting children who will
be riding in the 30 million vehicles now equipped
with passenger-side airbags throughout their 20-year
vehicle life.
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7 of 7
Reducing Risks to Children in Vehicles With Passenger Airbags
John D. Graham, Sue J. Goldie, Maria Segui-Gomez, Kimberly M. Thompson, Toben
Nelson, Roberta Glass, Ashley Simpson and Leo G. Woerner
Pediatrics 1998;102;e3
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Pediatrics is the official journal of the American Academy of Pediatrics. A monthly publication, it
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Reducing Risks to Children in Vehicles With Passenger Airbags
John D. Graham, Sue J. Goldie, Maria Segui-Gomez, Kimberly M. Thompson, Toben
Nelson, Roberta Glass, Ashley Simpson and Leo G. Woerner
Pediatrics 1998;102;e3
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http://pediatrics.aappublications.org/content/102/1/e3
Pediatrics is the official journal of the American Academy of Pediatrics. A monthly publication, it
has been published continuously since . Pediatrics is owned, published, and trademarked by the
American Academy of Pediatrics, 141 Northwest Point Boulevard, Elk Grove Village, Illinois,
60007. Copyright © 1998 by the American Academy of Pediatrics. All rights reserved. Print ISSN:
.
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