 Figure 1 - FMVSS 214 Side Impact Test Configuration. Linear dimensions are in inches, where 1 in. = 25.4 mm. |
Report to Congress
NHTSA Plan for Achieving
Harmonization of the U.S. and
European Side Impact Standards
April 1997
In the Congressional Conference Report 104-785 accompanying H.R. 3675, which provided funding for side impact testing in the New Car Assessment Program, the conferees note that "there are substantial differences between the U.S. side impact standard and the new European standard. These differences are inconsistent with the need for the international harmonization of motor vehicle safety standards. Therefore, NHTSA [National Highway Traffic Safety Administration] is directed to submit a report to the House and Senate committees on Appropriations by April 30, 1997, on the agency's plan for achieving harmonization of the side impact standard." This report responds to that directive and presents a review of the U.S. side impact standard, the recent European Union (EU) side impact directive and the agency's proposed plan to examine the potential for international harmonization of side impact requirements.
NHTSA has long recognized the need to move forward on harmonizing existing regulations and to create a forum for international research that ensures the development of future regulations that are compatible. NHTSA has been and continues to be involved in the vehicle safety regulatory efforts of the Economic Commission for Europe (ECE) of the United Nations, the EU, as well as with the governments of Japan, Australia, and Canada. NHTSA is committed to carrying out the presidential initiatives of the New Transatlantic Agenda, including promises to achieve global regulatory uniformity and to encourage a collaborative approach in testing and certification procedures by promoting greater compatibility of standards and health and safety-related measures.
NHTSA's initiatives with respect to side impact regulation harmonization began in 1979, when the agency presented a complete description and status of its research and rulemaking activities for upgrading side impact protection to the international community at the Seventh International Technical Conference on Experimental Safety Vehicles (ESV Conference) in Paris, France in June 1979. A subsequent Public Meeting was held in early 1980 with attendees from the European governments and industry. In 1990, NHTSA concluded that it was imperative to move forward with a side impact standard due to real world crash data evidence indicating that fatalities and injuries could be greatly reduced if a standard was mandated. Beginning September 1, 1996, all passenger cars marketed in the U. S. were required to meet this standard. On September 1, 1998, this regulation will be extended to light trucks, vans, and sport utility vehicles. In 1996, the EU adopted side impact requirements that will be applicable to new and redesigned passenger cars beginning October 1, 1998, and all passenger cars beginning October 1, 2003.
Although both address the side crash safety problem, as noted by Congress there are significant differences in the prescribed test procedures and requirements between the U.S. standard and the EU directive. Different crash test barriers, dummies and injury criteria are used for the U.S. Standard 214 than prescribed for the EU directive. The Functional Equivalence Process, developed by NHTSA in coordination with industry and consumer groups, will be directly applied in assessing harmonization of these requirements. NHTSA will determine the potential for international harmonization by:
NHTSA will perform any necessary research to fill voids in knowledge and will assess the time and resources necessary to carry this effort forward.
NHTSA recognizes that a lack of specific funding for crash testing and research to support this effort is a limiting factor. In addition, NHTSA will need to conduct the requisite benefit and cost analysis and rulemaking prior to any final decision that would change the existing U.S. standard.
2. Agency Harmonization Efforts
3. U.S. and EU Side Impact Regulations
3.1 Current U.S. Side Impact Standard
3.2 Current European Side Impact Standard
3.3 Past NHTSA Comparisons of U.S. and EU Side Impact Standards
4. NHTSA Plans for Side Impact Harmonization
4.2 Current NHTSA Testing to EU Regulation
4.3 Future Research and Development Tasks
4.3.2 Testing EU Compliant Vehicles to U.S. and EU Regulation
4.4 A Synopsis of Functional Equivalence/Harmonization Outcomes and Their Analysis
5. Issues for Consideration During Harmonization Process
6. Time and Cost Estimates for Harmonization Plan
The purpose of Federal Motor Vehicle Safety Standard (FMVSS) No. 214, Side Impact Protection, is to reduce the risk of serious and fatal injury to occupants of passenger cars, multipurpose passenger vehicles, trucks and buses in side impact crashes. The final rule for the crash test portions of the standard was phased-in beginning with 1994 model year (MY) production passenger cars and required 100 percent compliance by 1997 MY. In Europe, although efforts for developing a side impact regulation have been in process for many years, it is only recently that European Union (EU) Directive 96/27/EC was adopted. In general, both the U.S. and the EU side impact standards address the same safety needs, i.e., to reduce fatalities and injuries in side crashes. However, there are major variations in test procedures and performance criteria between the two that may lead to or require different vehicle designs, creating barriers to trade that are inconsistent with the New Transatlantic Agenda and Action Plan signed by President Clinton in December 1995 in Madrid. Speaking at the Conference of Enhanced Safety of Vehicles in May 1996, spokesmen for domestic and foreign automobile manufacturers expressed similar concerns over the differences in the U.S. and EU side impact regulations. On September 16, 1996, Congressional conferees noted these variations in the standards and stated that such "differences are inconsistent with the need for the International Harmonization of motor vehicle safety standards." The conferees directed the National Highway Traffic Safety Administration (NHTSA) to study these differences and to submit a report to the House and Senate Committees on Appropriations by April 30, 1997, outlining the agency's plan for achieving harmonization of side impact standards.
2.1 Overall Efforts
NHTSA has long recognized the need to move forward on harmonizing existing regulations and to create a forum for international research that ensures the development of future regulations that are compatible. NHTSA has been and continues to be involved in the regulatory efforts of the Economic Commission for Europe (ECE) of the United Nations, as a regular participant of the ECE's Working Party on the Construction of Vehicles (WP29) meetings and those of ECE's working groups of experts. These bodies develop and approve motor vehicle regulations, which are eventually adopted by member countries, especially by the European Union and its member states. NHTSA's participation in the deliberations on specific regulations by these groups has increased the compatibility among European and U.S. regulations.
On November 10-11, 1995, a Transatlantic Business Dialogue (TABD) Conference, an initiative of the late Secretary of Commerce, Ron Brown, and Commissioner Bangeman of the European Union, was held in Seville, Spain. At the Conference, participants agreed on a series of joint recommendations to build a strong framework within which trade, investment, capital, and technology can flow across the Atlantic. On December 3, 1995, at the Madrid Summit, the President signed a joint European Union-U.S. "New Transatlantic Agenda" and Action Plan which incorporated a number of these recommendations, including promises to achieve global regulatory uniformity and to encourage a collaborative approach in testing and certification procedures by promoting greater compatibility of standards and health and safety-related measures. At the prompting of some participants of the Seville and Madrid summits, a broad cross-section of industry representatives decided to hold a Transatlantic Automotive Industry Conference on International Regulatory Harmonization, in Washington D.C., on April 10-11, 1996. During the Conference, the U.S. and European automotive industry made recommendations for actions by the U.S. and the European Union concerning (1) the international harmonization of motor vehicle safety and environmental regulation, (2) the intergovernmental regulatory process necessary to achieve such harmonization, and (3) the coordination of vehicle safety and environmental research.
NHTSA is committed to carrying out the Presidential initiatives of the New Transatlantic Agenda within the framework of existing legislation and procedural rules. Evidence of this commitment are: (1) joint efforts by NHTSA and the Environmental Protection Agency (EPA) in the drafting of a multinational proposal by the Steering Group of WP29 to establish an agreement on global harmonization in parallel with the amended 1958 Agreement that would be administered by WP29, thus transforming WP29 into a forum for the global harmonization of motor vehicle safety and environmental regulations; (2) the agreement achieved at the 15th International Technical Conference on the Enhanced Safety of Vehicles (ESV) on an International Harmonized Research Agenda (IHRA) that will facilitate the development of globally harmonized regulations based on the same science; (3) continuous participation in the Asia Pacific Economic Cooperation (APEC) and the North America Free Trade Agreement (NAFTA), two fora that encourage the elimination of technical barriers to trade; and (4) the development of a generic process for the assessment of functional equivalence of U.S. and other countries' safety regulations.
NHTSA has also held two public meetings to seek comments from a broad spectrum of the population on its harmonization activities. At those meetings NHTSA reiterated its commitment that: (a) the safety benefits of U.S. standards will not be reduced; and (b) where a U.S. standard proves to be less stringent than that of another country, it would be upgraded within the framework of NHTSA procedural rules.
2.2 Side Impact Harmonization Efforts
NHTSA's initiatives with respect to side impact regulation harmonization began in 1979, when the agency presented a complete description and status of its research and rulemaking activities for upgrading side impact protection to the international community at the Seventh International Technical Conference on Experimental Safety Vehicles (ESV Conference) in Paris, France in June 1979. In the ESV Conference proceedings, NHTSA stated that:
"The need for improved side impact protection is clear. The program described here is intended to address this problem by means of a U.S. Federal Motor Vehicle Safety Standard. However, the need is certainly not limited to the United States nor are the countermeasures that will result from this program necessarily limited to vehicles which are used in the U.S. Because of the universal nature of this problem, NHTSA welcomes any and all contributions and cooperation from the international community. As one step toward solving this international problem, NHTSA expects to work closely with the Group of Experts on the Construction of Vehicles (WP29) of the United Nations. A public meeting is also being planned for later this year to discuss this program. All relevant comments on either the national program presented or a similar international program under the auspices of WP29 would be welcome at this time."
Later in 1979, NHTSA issued a notice for the public meeting to discuss the issues related to the development of a side impact regulation. The public meeting was held on January 31 and February 1, 1980. Attendees included the European governments and industry. Subsequent meetings were also held in Europe to discuss the initiatives. In 1983, the European Experimental Vehicle Committee (EEVC) initiated a research program to develop a side impact dummy, EUROSID, and later EUROSID-1. The program was aimed at developing not only the dummy but also the barrier, the test procedure and the injury criteria. NHTSA collaborated with the Europeans in the testing and evaluation of EUROSID-1 prior to deciding which dummy to use in the final U.S. side impact regulation. However, at the time, EUROSID-1 had many technical problems, leading NHTSA to conclude that the best available dummy was the U.S. side impact dummy (SID), which had been developed between 1979 and 1982 [2]. Moreover, there was variability in the barriers and test procedures between the European and U.S. tests. More details on the agency's past comparison of the U.S. and EU procedures and dummies are given in Section 3.3 of this report. The U.S. concluded that it was imperative to move forward with a side impact standard because real world crash data indicated that fatalities and injuries could be greatly reduced if such a standard was mandated. The U.S. continued to be involved in the development of the European side impact regulation by sending technical representatives to the Meeting of Experts on Passive Safety held in Geneva.
3.1 Current U.S. Side Impact Standard
On October 30, 1970, the Federal Motor Vehicle Safety Standards (FMVSS) were modified by the addition of Standard 214; Side Impact Strength - Passenger Cars [3]. The standard went into effect on January 1, 1973. The purpose of the standard was to enhance side door strength to minimize the safety hazards caused by intrusion into the passenger compartment during a side impact. The test procedure required "quasi-static" loading applied by a rigid steel cylinder or semicylinder. Intermediate and peak crush force limits were established. This "quasi-static" requirement was extended to trucks, buses, and multipurpose passenger vehicles with a gross vehicle weight rating (GVWR) below 4,535 kg (10,000 lbs), effective September 1, 1993 [4]. The agency's 1982 evaluation of this "quasi-static" requirement indicated that the standard was effective in side impacts of single vehicles into fixed objects but provided little benefit for occupants in vehicle-to-vehicle collisions.
On October 30, 1990, a final rule was published adding a dynamic impact requirement for passenger cars to FMVSS 214; Side Impact Protection [5] to address fatalities and injuries in vehicle-to-vehicle collisions. The requirement was phased-in such that all passenger cars made after September 1, 1996, had to comply. Subsequent to this action, a final rule was published requiring all trucks, buses, and multipurpose passenger vehicles under 2,721 kg (6000 lbs) to meet the same dynamic impact requirement by September 1, 1998 [6].
The dynamic test procedure focused on the measurement of anthropomorphic test dummy acceleration responses that have been correlated with occupant injuries. A schematic of the test configuration is shown in Figure 1. The dynamic test simulates the 90 degree impact of a striking vehicle traveling 48.3 kph (30 mph) into a target (test) vehicle traveling 24.2 kph (15 mph). This is achieved by a moving deformable barrier (MDB), with all wheels rotated 27 degrees (crab angle) from the longitudinal axis, impacting a stationary test vehicle with a 54 kph (33.5 mph) closing speed. For a typical passenger car, the left edge of the MDB is 940 mm (37 in.) forward of the mid point of the struck vehicle wheel base. The MDB has a total mass of 1367 kg (3015 lbs). The aluminum honeycomb of the barrier face is specified by design. The bottom edge of the MDB is 280 mm (11 in.) from the ground. The protruding portion of the barrier simulating a bumper is 330 mm (13 in.) from the ground.
Figure 1 - FMVSS 214 Side Impact Test Configuration. Linear dimensions are in inches, where 1 in. = 25.4 mm. |
The dimensions and material characteristics of the MDB face are shown in Figure 2. This was initially derived from the weights of passenger cars and lights trucks in the U.S. fleet with a adjustment made assuming a downward trend in vehicle mass due to fuel economy needs [7, pg IIIA-6].
 Figure 2 - FMVSS 214 Side Impact Deformable barrier Face. Linear dimensions are in inches, where 1 in. = 25.4 mm. |
Side Impact Dummies (SID) are placed in front and rear occupant positions on the side of the vehicle which is being struck. The instrumented dummies must exhibit rib, spine and pelvic accelerations below specified thresholds in order to pass the test. The rib and spine accelerations are combined into a single metric called the Thoracic Trauma Index (TTI(d)) which has an 85g limit for 4-door vehicles and a 90g limit for 2-door vehicles. The pelvic acceleration has a 130g limit.
3.2 Current European Side Impact Standard
The European Union side impact safety regulation, EU Directive 96/27/EC, is similar to FMVSS 214 in that a MDB is launched into a stationary target vehicle equipped with a single instrumented front seat dummy. This directive was approved by the EU in October 1996. It will apply to all new or redesigned models manufactured after October 1, 1998, and all other vehicles manufactured after October 1, 2003. The procedure and test equipment differ from those in FMVSS 214 in many significant ways. The MDB impacts the target vehicle at 50 kph (31 mph) and 90 degrees with no crab angle, as shown in Figure 3. This differs from FMVSS 214 in that no attempt is made at simulating the movement of the target vehicle. The lateral striking position is aligned with the occupant seating position rather than the vehicle wheelbase. The dimensions of the European barrier face are given in Figure 4. The barrier face is segmented into six blocks with specific force deflection characteristics. The barrier face is smaller and much softer than the U.S. barrier on the blocks closest to the sides. The bottom edge is the most forward part of the European MDB and is 300 mm (11.8 in.) from the ground. This is in comparison to the 280 mm (11.0 in.) high bottom edge and 330 mm (13 in.) bumper height in the U.S. barrier face. The European barrier has a mass of 950 kg (2095 lbs) compared to 1367 kg (3015 lbs) for the U.S. barrier.
 Figure 3 - EU Directive 96/27/EC Side Impact Test Configuration |
 Figure 4 - EU Directive 96/27/EC Side Impact Deformable Barrier Face. Dimensions are in millimeters where 25.4 mm = 1 in. |
As in FMVSS 214, for EU Directive 96/27/EC successful test performance is determined by dummy injury criteria. However, both the test dummy and injury criteria differ from those in FMVSS 214. SID is capable of measuring acceleration of the ribs, spine and pelvis. These readings are the bases for the U.S. injury criteria. EUROSID-1 has the capability of measuring more parameters than SID, including force and displacement as well as acceleration based readings [8]. The EU Directive places limits on five dummy measurements to determine vehicle performance. The head injury criteria (HIC) is derived from head acceleration and must remain below 1000. A rib deflection of 42 mm (1.7 in.) is allowed in the thorax along with a Viscous Criterion (V*C) of 1 m/s. The Viscous Criterion is calculated from combined rib displacement and velocity. The abdominal force is limited to 2.5 kN (562 lbs). Finally, the Pubic Symphysis force, which is in the pelvic region, must be less than 6 kN (1350 lbs).
3.3 Past NHTSA Comparisons of U.S. and EU Side Impact Standards
3.3.1 Side Impact Test Dummies and Injury Criteria
As stated above, the U.S. and EU side impact regulations use very different test dummies. In addition to SID and EUROSID-1, a third impact dummy known as BIOSID has undergone extensive use and evaluation. Schematics of these three dummies are shown in Figure 5. The University of Michigan Highway Safety Research Institute under contract with NHTSA developed SID in the 1979 to 1982 time frame. The EEVC developed the prototype EUROSID from 1983 to 1985 through several research laboratories. After preliminary evaluations, further refinements led to a production version known as EUROSID-1 in 1989. Major components of the BIOSID test dummy were developed by General Motors. The Society of Automotive Engineers (SAE) Side Impact Dummy Task Force completed the BIOSID development.
The injury criteria measured by SID in FMVSS 214 are TTI(d) and pelvic acceleration. TTI(d) was derived and validated from a large cadaver data base [9, pg.IIIB-34]. At the time of addition of the dynamic impact requirement for passenger cars to FMVSS 214, the agency believed that vehicles designed with countermeasures which reduce these injury criteria would more adequately protect humans against injury in side crashes than vehicles without these countermeasures.
As stated in Section 3.1, SID is designed to measure thoracic (TTI(d)) and pelvic acceleration. As detailed in Section 3.2, EUROSID-1 has additional measurement capabilities beyond those in SID. BIOSID measurement capabilities are analogous to those of EUROSID-1. Prior to issuance of the dynamic portion of FMVSS 214 for passenger cars, NHTSA initiated a research program to study all three side impact dummies to determine their potential for use in the regulation. The dummies were evaluated through laboratory and full vehicle crash tests [10, 11]. The biofidelity of EUROSID-1 and BIOSID as compared to SID were assessed based only on the TTI(d) and pelvic acceleration.
NHTSA used a parameter called coefficient of variation (CV%) to determine the repeatability of test results. A lower CV% indicates a more repeatable result. Pendulum tests showed that SID and BIOSID had similar coefficients of variation for rib, lower spine and pelvic responses. EUROSID-1 had a higher CV% for the lower rib, but much lower coefficients of variation for all other responses. In sled tests, essentially the same padding stiffness minimized the responses of all three dummies. In comparison to cadaver results, for sled impacts in a padded environment, SID and BIOSID showed good biofidelity for the responses measured. Because of difficulties with EUROSID-1 during testing, data was limited, thus making it difficult to determine the full biofidelity of this device. Only the SID and BIOSID were compared in the full scale vehicle crashes. The front seated dummies showed good agreement, but the rear seated dummies did not.
In general, the initial NHTSA evaluation of alternative side impact test dummies showed that BIOSID deserved consideration for possible future use in FMVSS 214 [9, pg.IIIB-59]. There was not enough information to make the same determination for EUROSID-1 and in addition it appeared likely that this device would undergo additional design changes.
3.3.2 Movable Deformable Barrier and Test Procedure
The MDB defined in FMVSS 214 was designed to be representative of the mass and size of U.S. vehicles. The angle of impact represents the most common side crash. The relative longitudinal and lateral speed of the MDB and target vehicle is considered the threshold for serious injury in actual crashes [9 pg.IIIA-44]. At the time of issuance of the dynamic portion of FMVSS 214 for passenger cars, NHTSA analyzed industry data in order to evaluate the European MDB and test procedure. Using data generated by the American Automobile Manufacturers Association (AAMA), the agency concluded that the variability of the European procedure and barrier in conjunction with EUROSID-1 was slightly higher than NHTSA's procedure and barrier with SID [9, pg.IIIA-84]. This result was for a single barrier face designed by EEVC and made of urethane foam.
Crash tests performed by Volkswagen AG showed 25 percent and 67 percent lower TTI(d) than the U.S. barrier for two different European barrier designs. These tests were performed using SID and indicate the European barrier produced a less severe result. NHTSA also examined testing performed by Transport Canada using the EEVC designed European barrier and procedure, which gave more severe results than the U.S. barrier and procedure. NHTSA concluded that this was due to the foam EEVC barrier disintegrating upon impact. Clearly, the performance based method of specifying the EU barrier stiffness lead to conflicting results in crash tests.
The Functional Equivalence Process, recently developed by NHTSA in coordination with industry and consumer groups, will be directly applied in assessing harmonization between the U.S. regulation and the EU directive. A public workshop on the process was held at NHTSA on January 16, 1997 [1]. A flowchart and explanatory notes showing the generic process can be found in Appendix B. Reduced to its basic terms, regulations are considered functionally equivalent when they address the same safety need and provide the same or greater safety benefit.
As noted above, the U.S. regulation and the EU directive are intended to address the side crash safety problem. However, as also noted above and by Congress, there are significant differences in the prescribed test procedures and requirements. Different crash test barriers, dummies and injury criteria are used for the U.S. regulation than prescribed for the EU directive. NHTSA will determine the potential for international harmonization of these requirements by:
NHTSA also will perform any necessary research to fill voids in knowledge and will assess the time and resources necessary to carry this effort forward.
4.1 Plan Diagram
Figure 6 is a flowchart depicting the specific side impact harmonization plan. The basic requirement of this plan is that any final outcome must maintain or exceed the safety benefits associated with the current U.S. Regulation. The Functional Equivalence Process was applied in the development of this plan. Since EU Directive 96/27/EC addresses the same safety need as FMVSS 214, the first step, as shown in Appendix B, for entry into the functional equivalence process is met. However, it is recognized that the differences in requirements, test conditions, and test procedures between the U.S. regulation and the EU directive are not insignificant and may have safety consequences.
As stated in the Functional Equivalence Process, the preferred means of determining if regulations have the same benefits is real world crash data from vehicles meeting each standard. The U.S. regulation was phased in for passenger cars beginning with MY 1994 and is applicable for all cars for MY 1997. Therefore, some limited real world crash data are available for U.S. compliant vehicles. No real world crash data are available on vehicles which meet the EU directive since these requirements do not become effective until MY 1999. From the Functional Equivalence Process, the next best means of determining the relative safety benefits is compliance test data. For the U.S. regulation, this information is available on approximately 70 passenger cars that have been tested in NHTSA's safety assurance program. Comparable data may not be available for passenger cars that meet the EU directive. The first step of the harmonization plan, as shown in Figure 6, will be to obtain and assess any available industry and government research data comparing the two regulations, especially full scale vehicle compliance tests. Since NHTSA's initial evaluation and comparison of alternative barriers, procedure and dummies, a significant body of research has been created comparing these parameters. For example, the Australian Federal Office of Road Safety compared the U.S. and EU regulations by means of a Harm Reduction method [13]. They estimated that, in Australian dollars, FMVSS 214 would provide a $147 benefit per car as compared to a $159 benefit per car for the EU regulation. Based on this the study recommended that all vehicles sold in Australia meet either regulation.
In parallel with this assessment of outside data, the agency will carry out compliance tests to the EU regulation. The vehicles tested will be identical to vehicles which successfully completed U.S. compliance testing. These tests are underway and targeted for completion in the summer of 1997. Details on this EU regulation testing are presented in Section 4.2.
Completion of this initial phase of testing and data analysis will place NHTSA at a major decision point in the Functional Equivalence Process (i.e., Is there sufficient data to assess the functional equivalency of the two standards, if not could additional research be conducted to generate data?). The assessment for this decision is represented by the first three diamonds in the Figure 6 flowchart. First, any non-trivial problems with the test procedure or dummy must be identified. Next, it will be determined if the EU and U.S. regulations provide the same level of safety performance for the tested set of vehicles. Finally, the acceptability of the EU regulation as an alternative or replacement for the U.S. regulation (with adjustments in injury criteria if required) will be ascertained. The final step is essentially a determination of functional equivalence. If the EU regulation is found to be an acceptable alternative or replacement, rulemaking in the U.S. could be initiated and the functional equivalence/harmonization process would be complete. However, it may be that there is not sufficient information for this determination or that functional equivalence is clearly not possible. If it is only a matter of conducting additional vehicle tests and analyses, NHTSA would continue such an effort and iterate through the Functional Equivalence Process steps. However, if other problems are apparent in performing the EU tests (see Section 5 for a summary of issues that could surface during the testing or that may need further assessment) or if each standard indicates unrelated safety performance for the same vehicle, the harmonization plan will need to proceed in a different direction as suggested in the lower portion of Figure 6.
The next steps in this different direction would be to determine what additional information is needed to accept or exclude functional equivalence and any other potential harmonization solutions. A U.S. position on harmonization can then be established in preparation for meetings with European regulatory officials and technical advisory committees. The meetings would ascertain the extent to which the Europeans are willing to consider changes to their regulation and establish a coordinated research agenda. It is possible that after meeting with the Europeans that no path for complete or partial harmonization is open. At this stage, once again, the functional equivalence/harmonization process could be terminated. It may also be the case that through compromise and information provided by the Europeans, harmonization is directly achievable.
Rather than either terminating or achieving harmonization after meeting with our European counterparts, it is likely that further research will be undertaken to fill voids in knowledge. To eliminate duplication in work and to leverage resources, NHTSA will meet with Industry through the Vehicle Aggressivity and Compatibility Working Group (VACWG) of the Motor Vehicle Safety Research Advisory Committee (MVSRAC). The agency met with the MVSRAC previously to discuss the initial phase of crash testing to the EU regulation.
As the flowchart indicates, the series of steps where NHTSA meets with industry and the Europeans and performs required research are iterative. They will be repeated as necessary to obtain the knowledge required for harmonization or to determine that it is not feasible. At each step an assessment of the necessary time and resources will be made and funding may be sought. Also, public meetings will be held and public comment solicited as appropriate. Throughout the entire harmonization process NHTSA will meet all legal requirements and follow all established procedures. Although not shown in the flowchart, any proposed change to the current regulation must be justified based on an assessment of costs and benefits. See Section 4.4 for further information related to this topic.
4.2 Current NHTSA Testing to EU Regulation
NHTSA has initiated a research program to assess the performance of U.S. compliant vehicles using EU Directive 96/27/EC. The vehicles included in this program are identical in design to vehicles tested to FMVSS 214 by NHTSA in the compliance test program. Three of these vehicles have also been included in the side impact New Car Assessment Program (NCAP). The selected vehicles are listed in Table 1. The test results will be evaluated to determine the level of safety performance of the vehicles in the matrix for both the U.S. and EU regulation and establish the probability of occupant injury based on the injury measures.
The detailed selection criteria for the vehicles in Table 1 can be found in Appendix A. In addition to selecting vehicles previously tested to FMVSS 214, the vehicles chosen have shown a range of side impact performance results based on the TTI(d) injury measure. Vehicles were also chosen to be representative of the major manufacturers.
| Vehicle | Doors | Side NCAP |
| Ford Taurus | 4 | Yes |
| Volvo 850 | 4 | Yes |
| Nissan Sentra | 4 | No |
| Hyundai Sonata | 4 | Yes |
| Ford Mustang | 2 | No |
| Lexus SC300 | 2 | No |
| Geo Metro | 2 | No |
| Mitsubishi Eclipse | 2 | No |
To date, NHTSA has met with industry through MVSRAC on January 10 and February 24, 1997. In the first meeting, the agency presented both its immediate proposal for testing U.S. compliant vehicles to the current EU standard and the agency's overall side crash protection research program. The MVSRAC industry members were asked to participate with NHTSA in the first phase of testing by providing data from vehicles tested to the Directive 96/27/EC, or by providing vehicles that NHTSA could test independently. The industry was responsive and, to date, the result of this request was the following: GM has supplied a Geo Metro; Chrysler will be supplying data for the Dodge Stratus; Ford has loaned NHTSA a EUROSID-1 dummy plus instrumentation and is supplying a Ford Taurus and possibly a Ford Thunderbird; Volvo is supplying a Volvo 850; Mitsubishi has provided test data for the Mitsubishi Eclipse; Saab has provided data for the Saab 900s; and Volkswagen/Audi has provided partial data for the Audi 90. Ford has also recently conducted EU standard testing for their Taurus and Contour vehicles and will be supplying the data to NHTSA. It is worth noting that with the exception of test data to be supplied by Ford, the data supplied from the other manufacturers are from earlier EU side impact testing. Such testing utilized MDB faces from different suppliers with varying dynamic responses. NHTSA will not be able to use these data in its primary analysis because industry and agency experience has shown that using MDBs with varying dynamic response in EU side impact testing will lead to unpredictable vehicle performance.
In parallel with FMVSS 214 requirements, NHTSA is using two EUROSID-1 dummies in its EU side impact testing, a dummy in the driver's position and a dummy in the rear right seat passenger position. This is in contrast to using only one dummy in the driver position as specified in the EU Directive 96/27/EC. This will provide data to compare with existing FMVSS 214 data for the same vehicles. The use of a rear seat dummy will be an issue that will have to be resolved with the EU. The agency's position is that the protection for the rear seat occupant must be provided by any side impact regulation in that the relaxation of this requirement would be a reduction in safety benefits that are in the present U.S. standard.
4.3 Future Research and Development Tasks
Section 4.3.1 discusses an ongoing biomechanics test program whose results may be used during the harmonization process related to the side impact dummies. Sections 4.3.2 and 4.3.3 are possible future research tasks. These tasks or others become more likely if the initial phase of testing does not lead directly to acceptance of the EU regulation. They are listed to give a sense of what types of research tasks may be necessary to acquire the knowledge required for harmonization to move forward.
4.3.1 Cadaver Sled Tests
NHTSA has been performing side impact sled tests with cadavers to establish biofidelity corridors. Nineteen have been performed and five additional tests are scheduled this fiscal year to complete the study. This information may be used to further evaluate SID, EUROSID-1 and BIOSID and the validity of the injury criteria measured by each dummy. Also, a correlation between the different injury criteria may be developed.
4.3.2 Testing EU Compliant Vehicles to U.S. and EU Regulation
As stated previously, the differing side impact requirements in the U.S. and EU may cause different countermeasures to be designed into the vehicles sold in each market. The first phase of testing described in Section 4.2 is a set of eight U.S. compliant vehicles tested to the EU regulation. Presumably these vehicles were designed to meet the U.S. regulation. Through cooperation with industry, an attempt could be made to identify vehicles designed to meet the EU or both the EU and U.S. regulations. If such vehicles exist they could be tested to both regulations. This set of information could then be used to give an even clearer indication of the relative safety benefits of each regulation.
4.3.3 Performing the EU Test at Side NCAP Speeds
At least three of the vehicles listed in Table 1 have also been tested in the Side NCAP program. This program performs the standard compliance testing, but at a higher impact speed. It may yield useful data to test identical vehicles, and possible others, to the EU regulation, but at a speed comparable to the Side NCAP tests. This would provide comparisons of vehicle performance in an EU-NCAP type test and would evaluate EUROSID-1 in a more severe test environment. These tests would not be part of the formal NCAP program, but rather a research project. NHTSA intends for NCAP side impact tests to be conducted following the same procedures as adopted for any U.S. side impact standard (e.g., if the EU regulation is found to meet all of the agency's requirements for harmonization and safety needs and is adopted in the U.S., then the EU procedure would be used for NCAP, with the exception of impact speed).
4.3.4 Testings of More Side Air Bag Equipped Vehicles
Side air bag systems and other dynamically deployed side impact restraints are being introduced in several vehicle models. In the current test program described in Section 4.2, one side air bag equipped vehicle (Volvo 850) is being tested. This was the only side air bag equipped vehicle which met the selection criteria. However, vehicles with such systems, being market driven, are projected to become more prevalent. From compliance and NCAP test results, SID is adequate in measuring the performance of side air bag systems. However, the capability of EUROSID-1 in assessing side air bag systems is unknown. In addition, neither standard addresses possible harm from the deploying systems to children and adults in out-of-position seating when involved in a side crash. Crash tests to both the EU and U.S. regulation may be run on more side air bag equipped vehicles to assure that a harmonized standard correctly addresses these issues.
4.4 A Synopsis of Functional Equivalence/Harmonization Outcomes and Their Analysis
It is evident from the side impact functional equivalence/harmonization plan presented that there is a range of possible final outcomes. With respect to functional equivalence, the following four outcomes are possible:
If the functional equivalence assessment concludes with the fourth outcome, NHTSA will continue the harmonization process as previously discussed and illustrated in the lower section of Figure 6. This may result in other outcomes such as:
If the end result of the harmonization process is anything other than maintaining the status quo, the normal rulemaking process in each country will be necessary and an assessment of costs and benefits must be performed before a change to the current regulation is made. Additional research may be needed to obtain the information required for this analysis. It is also feasible that this analysis may be used to select among several competing options.
The cost/benefits analysis will consider the costs associated with redesigning and manufacturing vehicles to be compliant with the altered regulation. Although the altered regulation must have equal or greater safety benefit, the type and frequency of occupant injury may change with associated changes in societal costs. It will also be critical to account for the reductions in costs to manufacturers commensurate with only having to meet a single standard. This is, after all, the main reason for initiating the side impact harmonization process.
The goal of this section is to briefly present problems/issues which have not been focused on previously in this report and which may be necessary to overcome to achieve the goal of harmonization. These issues are, in the short term, obstacles to a determination of functional equivalence and, in the long term, obstacles to the creation of an unified standard.
Table 2 shows the cost estimates for the initial series of vehicle testing and data analysis. These funds were provided from NHTSA's FY 97 research and development funds. Figure 7 is a chart showing the initial harmonization research as specific tasks with assumed start and end dates. The cost estimates associated with initial research tasks of the harmonization plan are given in Table 3.
Table 2 - Cost of Initial Series of Tests of 8 Vehicles to EU Side Impact Regulation.
| Description | FY 97 Cost |
| Vehicles | $117,000 |
| Barrier Faces | $ 24,000 |
| EUROSID-1 and Instrumentation | $160,000 |
| Testing | $164,000 |
| Analysis | $ 25,000 |
| Total | $490,000 |
The results from the first vehicle test series (Phase I) may reveal non-trivial problems and may also indicate significant differences in the safety performance of the vehicles tested in the EU side impact test versus their performance in the FMVSS 214 test. This could necessitate specific tasks to be completed before the additional full vehicle tests (Phase II) as outlined below. The definition and magnitude of these specific tasks, if required, cannot be defined until the completion of Phase I. In addition, the type of full vehicle tests to be performed in Phase II will be highly dependent on the initial results and meetings with EU and industry officials. Therefore, the cost and time estimates for these tasks are rough approximations. Finally, as stated in section 4.1, some aspects of the harmonization plan may be iterative. Task 6 - 17 in Figure 7 may, in whole or part, need to be repeated to achieve harmonization. The cost and time estimates represent a single iteration of these steps.
| Project Description | Cost (x1000) | ||
| FY 97 | FY 98 | ||
| Phase I Vehicle Testing | Test and Analyze 8 Vehicles to EU Regulation | $490 | |
| Analyze Industry and Government Data | $ 25 | ||
| Phase II Vehicle Testing | Test and Analyze 4 EU Vehicles to US and EU Regulations | $350 | |
| Test and Analyze 5 Vehicles to EU Reg. at NCAP Speed | $220 | ||
| Test and Analyze 3 Air Bag Vehicles to US and EU Regs. | $265 | ||
| Biomechanics Research | Sled Test and Analyze Cadavers to Assess Thorax | $200 | |
| Sled Test and Analyze Biofidelity of Dummies | $395 | ||
| Total | $515 | $1,430 | |
[1] Federal Register, Vol. 61, November 14, 1996, p. 58362.
[2] Code of Federal Regulation, 49, Part 572.40, "Subpart F - Side Impact Dummy 50th Percentile Male."
[3] Federal Register, Vol. 35, October 30, 1970, p. 16801.
[4] Federal Register, Vol. 56, June 14, 1991, p. 27427.
[5] Federal Register, Vol. 55, October 30, 1990, p. 45722.
[6] Federal Register, Vol. 60, July 28, 1995, p. 38751.
[7] NHTSA "Preliminary Regulatory Impact Analysis: New Requirements for Passenger Cars to Meet a Dynamic Side Impact Test, FMVSS 214," DOT HS 807 220, January 1988.
[8] ISO/TC22/SC12/WG5/N256, "Specification EUROSID-1 (January 1990)," April 1990.
[9] NHTSA "Final Regulatory Impact Analysis: New Requirements for Passenger Cars to Meet a Dynamic Side Impact Test, FMVSS 214," August 1990.
[10] Zuby, D.; Willke, D.T.; "Evaluation of BIOSID and EUROSID-1," Volume I and II, DOT HS- 807-807 and HS-807-808, July 1991.
[11] Kanianthra, J.N; Willke, D.T; Gabler, H.C; "Comparative Evaluation of SID, BIOSID, and EUROSID in Safety Performance Assessment in Side Impacts," Proc. 13th International Technical Conference on Experimental Safety Vehicles, Paris, France, November 1991.
[12] NHTSA Docket 88-6-N8-10, Attachment II, "AAMA: EUROSID-1 Concerns," May 12, 1995.
[13] Fildes, B; Digges, K; Carr, D; Dyte, D; Vulcan, P; "Side Impact Regulation Benefits," CR-154, Federal Office of Road Vehicle Safety, Canberra, Australia, June 1995.
The U.S. vehicles selected for testing to EU Directive 96/27/EC are shown in Table A1. The selection criteria used for vehicles to be tested to the European side impact procedure are described below along with supporting rational. The criteria are listed in descending order of importance. The assumption was made that funding will be available to test six or eight vehicles.
1. | FY 1994 - 1996 FMVSS 214 compliance test results are available and
the vehicles currently available for purchase are unchanged in anyway which
would affect the test results. This will allow the comparative ranking of
each vehicle according to FMVSS 214 and ECE 95. |
2a. | If eight vehicles are tested, four will be 4-door and four will be
2-door. If six vehicle are tested four will be 4-door and two will be
2-door. These ratios, as closely as possible, match the 6:4 ratio of 4-door
to 2-door in the general vehicle population, while being consistent with
criteria #2b [4]. |
2b. | Within each vehicle type, i.e., 4-door and 2-door half the vehicles
will have a front TTI(d) result as low as possible and half will be as high
as possible. Including a range of performance in the test matrix will
provide the most useful comparative data between vehicles and standards. |
3. | MY 1997 side impact NCAP test results are available for the
vehicles. This will provide an additional comparative data set at a higher
performance level for the current test program and possible future ECE 95
testing at a higher performance level. |
4. | All U.S. manufacturers will be represented by vehicles that they or
their subsidiaries make and/or sell. As many foreign manufacturers as
possible will be represented. |
5. | The highest production vehicles will be represented. |
6. | All major types of side protection restraint systems will be represented,
i.e., side air bag. |
Table A1 - U.S. vehicles selected for testing to EU Directive 96/27/EC
| Vehicle | Doors | Comp. MY | Comp. Front TTI(d) | Side NCAP | Annual Prod. (x1000) | Use in 8 Vehicle Matrix | Use in 6 Vehicle Matrix |
| Ford Taurus | 4 | 1995 | 50 | Yes | 539 | Yes | Yes |
| Volvo 850 | 4 | 1996 | 49 | Yes | 63 | Yes | Yes |
| Dodge Stratus | 4 | 1996 | 58 | Yes | 216 | Alternate | Alternate |
| Nissan Sentra | 4 | 1996 | 66 | Yes | 72 | Yes | Yes |
| Hyundai Sonata | 4 | 1996 | 73 | Yes | 15 | Yes | Yes |
| Kia Sephia | 4 | 1996 | 64 | Yes | 22 | Alternate | Alternate |
| Ford Mustang | 2 | 1996 | 56 | No | 170 | Yes | Yes |
| Lexus SC300 | 2 | 1995 | 63 | No | 13 | Yes | Alternate 1 |
| Ford T-Bird | 2 | 1995 | 68 | Yes | 191 | Alternate | Alternate 2 |
| Geo Metro | 2 | 1996 | 80 | No | 58 | Yes | Yes |
| Mitsub. Eclipse | 2 | 1996 | 82 | No | 111 | Yes | Alternate 1 |
| Dodge Avenger | 2 | 1996 | 82 | No | 71 | Alternate | Alternate 2 |
ULTIMATE GOAL
The ultimate goal in comparing standards addressing a particular problem is assessing the real world performance of the covered vehicles or equipment in reducing fatalities and injuries. The most reliable basis for making that assessment is fatality and injury data directly drawn from actual crashes. Accordingly, the countries involved in making functional equivalence determinations should make appropriate efforts to assure the availability of such data.
GUIDING PRINCIPLES
Best available evidence
Country A should base its FE determinations on the best available evidence. If available, estimates of real world safety benefits based on fatality and injury data directly drawn from actual crashes are the best evidence. If such data are not available, then estimates based on other information, such as compliance test data, may be used, although increased caution needs to be exercised in making judgments based on those estimates. If sufficient crash data regarding real world safety benefits are available, and a comparison of those benefits shows that the Country B standard is less beneficial than the Country A standard, Country A could avoid wasting resources making comparisons on the basis of less definitive types of evidence.
Sufficiency of evidence
Many types of data are available for a comparison of two standards. Often there is an abundance of one type of data and little or no data from other sources. If insufficient data are available, and such data either cannot be generated through engineering analysis (e.g., real world safety benefits estimates), or conducting additional research and development is not cost effective, then Country A should immediately stop consideration of such data and consider the other available data instead.
The horizontal path through the flowchart is intended to illustrate the sources of data that will be considered and a rough idea of the priority they will receive. Each step branches independently to the tentative determination of functional equivalency by its "yes" path. This may seem to preclude later steps once any "yes" path is encountered. In practice, however, all data sources will be considered to the extent that they are available before a determination of functional equivalency is made.
Best practices
Country A should pursue a "best practices" policy, i.e., Country A should propose to upgrade its standards when it concludes that a Country B standard offers greater benefits than its counterpart Country A standard.
Conservatism
Country A should place priority on preserving the safety benefits of its standards. Country A can best preserve those benefits by being conservative in reaching any conclusion that Country B standard is FE to its counterpart Country A standard.
Reciprocity
Country A should take steps to encourage reciprocity by Country B. When Country A's comparison of standards indicates that one of its standards has benefits equal to or greater than its counterpart Country B standard, Country A should forward the results of that comparison to Country B and request consideration be given by Country B to determining that the Country A standard is FE to its counterpart Country B standard.