Contents
LIST OF ABBREVIATIONS 5
Executive Summary 6
1. Introduction 7
1.1. FMVSS No. 301 Upgrade 7
1.2. Lead Time 8
1.3. Survey Sampling: Proportion of Compliance in Rear Impact Upgrade 9
1.4. Evaluation Purpose 10
2. Analysis Setting 11
2.1. Impact Directions and Rollover 11
2.2. Model Year and Calendar Year Setting 11
3. Analysis Method 12
3.1. Odds Ratio and Effectiveness 13
3.2. Pearson's Chi-Squared Test and Fisher's Exact Test 13
3.3. Z-Test of Two-Sample Proportions 14
4. Fires in Rear Impacts 14
4.1. Model Year Versus Rear Impact Fires in FARS 15
4.2. Rear Impact Upgrade Versus Rear Impact Fires in FARS 17
4.3. Model Year Versus Rear Impact Fires in Polk 19
4.4. Rear Impact Upgrade Versus Rear Impact Fires in Polk 20
5. Benefit Analysis in Rear Impact Fires 22
5.1. Percentage of Fatalities Attributable to Burns 23
5.2. Life-Saving Effectiveness 24
5.3. Benefit: Lives Potentially Savable in Rear Impacts 25
6. Fires in Side Impacts 27
7. Affiliated Effect of Rear Impact Upgrade 29
7.1. Fires in All Crash Events Excluding Rear Impacts 29
7.2. Fires in Frontal Impacts 32
7.3. Fires in First-Event Rollovers 33
8. Discussion 35
9. Appendix 37
9.1. Survey Sampling 37
9.2. Analysis of ESC in Rear Impact Fires 42
9.3. Analysis of ESC in First-Event-Rollover Fires 43
9.4. Vehicle Type Versus Rear Impact Fires in FARS 44
Table 1. Certification Percentage of FMVSS No. 301 Rear Impact Upgrade 8
Table 2. Compliance Test of FMVSS No. 301 Rear Impact Upgrade 10
Table 3. Principal Impact and O'Clock Position 11
Table 4. 2-by-2 Contingency Table 13
Table 5. Sample Proportions of Two Groups 14
Table 6. Frequency Table of Model Year Versus Rear Impact Fires in FARS 15
Table 7. Model Year Versus Rear Impact Fires in FARS 16
Table 8. Rear Impact Upgrade Versus Rear Impact Fires in FARS 18
Table 9. Model Year Versus Rear Impact Fires in Polk 20
Table 10. Rear Impact Upgrade Versus Rear Impact Fires in Polk 21
Table 11. Distribution of Fatalities Attributable to Burns 24
Table 12. Summary of Estimated Parameters 25
Table 13. Estimation of Life-Saving Effectiveness 25
Table 14. Statistical Inference of Benefit 26
Table 15. Frequency Table of Model Year Versus Side Impact Fires in FARS 28
Table 16. Model Year Versus Side Impact Fires in FARS 28
Table 17. Distribution of Crash Events in FARS 30
Table 18. Model Year Versus Fires in All Other Crash Modes in FARS 31
Table 19. Frequency Table of Model Year Versus Frontal Impact Fires in FARS 32
Table 20. Model Year Versus Frontal Impact Fires in FARS 33
Table 21. Frequency Table of Model Year Versus First-Event-Rollover Fires in FARS 34
Table 22. Model Year Versus First-Event-Rollover Fires in FARS 34
Table 23. Compliance Test of Rear Impact Upgrade 37
Table 24. Compliance Test in 1999 and Honda Accord in 2012 38
Table 25. Compliance Test in 2012 40
Table 26. Estimation of Compliance Proportion in Test Year 2012 41
Table 27. Estimation of Compliance Proportion 41
Table 28. Logistic Regression in Rear Impact Fires 42
Table 29. Fire-Reducing Effectiveness in Rear Impact Fires 42
Table 30. Logistic Regression in First-Event-Rollover Fires 43
Table 31. Fire-Reducing Effectiveness in First-Event-Rollover Fires 43
Table 32. (Cars) Model Year Versus Rear Impact Fires in FARS 44
Table 33. (LTVs) Model Year Versus Rear Impact Fires in FARS 45