Motorcoach Flammability Project Final Report: Tire Fires - Passenger Compartment Penetration, Tenability, Mitigation, and Material Performance | NIST

.................................................................................................................................. iii LIST OF FIGURES ....................................................................................................................... vi LIST OF TABLES ....................................................................................................................... xiii LIST OF ABBREVIATIONS ...................................................................................................... xiv INTRODUCTION .......................................................................................................................... 1 LITERATURE REVIEW ............................................................................................................... 3 Previous Studies Related to Bus and Motorcoach Fires ............................................................. 3 1980s NIST Experiments ........................................................................................................ 3 1990s UK Experiments ........................................................................................................... 4 Experiments in China .............................................................................................................. 5 Experiments at SINTEF (Norway) ......................................................................................... 6 Experiments at SP (Sweden) ................................................................................................... 6 Material Flammability Testing ................................................................................................. 10 FLAMMABILITY TESTING OF ACTUAL MOTORCOACH MATERIALS.......................... 13 Overview ................................................................................................................................... 13 Test Results ............................................................................................................................... 15 EXPERIMENTAL SET-UP ......................................................................................................... 20 Experimental Preparation.......................................................................................................... 20 Obtaining the Motorcoach .................................................................................................... 20 Moving and Securing the Motorcoach .................................................................................. 20 Straightening Window Posts ................................................................................................. 21 Removing Unsafe Materials ................................................................................................. 25 Replacement Components .................................................................................................... 25 Burner ................................................................................................................................... 25 Modifications for Fire-hardening Experiments .................................................................... 28 Modifications for the Tenability Experiment ....................................................................... 32 Measurement Instrumentation .................................................................................................. 36 Total and Burner Heat Release Rates ................................................................................... 37 Temperature .......................................................................................................................... 37 Heat Flux ............................................................................................................................... 45 Gas Volume Fractions........................................................................................................... 49 Visibility ............................................................................................................................... 49 Image Recording ....................................................................................................................... 53 Standard and Infrared Video ................................................................................................. 53 Still Photography .................................................................................................................. 56 General Procedures ................................................................................................................... 56 Extinguishment ..................................................................................................................... 57 RESULTS AND DISCUSSION ................................................................................................... 58 Penetration Experiments ........................................................................................................... 58 Event Timing ........................................................................................................................ 58 Photographs........................................................................................................................... 60 Heat Release Rate ................................................................................................................. 74 Wheel, Tire, and Wheel Well Temperatures ........................................................................ 76 Window and Panel Temperatures ......................................................................................... 79 THIS IS A PREDECISIONAL DRAFT INTERIM REPORT v Floor, Lavatory, and Central Tunnel Temperatures .............................................................. 84 Axle Temperatures ................................................................................................................ 88 Heat Fluxes ........................................................................................................................... 90 Fire-hardening Experiments...................................................................................................... 92 Event Timing ........................................................................................................................ 92 Photographs........................................................................................................................... 93 Heat Release Rate ................................................................................................................. 99 ABS Sensor ......................................................................................................................... 102 Extinguishment ................................................................................................................... 105 Tenability Experiment ............................................................................................................ 105 Event Timing ...................................................................................................................... 105 Photographs......................................................................................................................... 106 Repeatability ....................................................................................................................... 108 Heat Release Rate ............................................................................................................... 109 Interior Gas Temperatures .................................................................................................. 110 Heat Fluxes ......................................................................................................................... 111 Thermal Tenability Analysis............................................................................................... 112 Other Temperature Measurements ...................................................................................... 115 Gas Volume Fractions......................................................................................................... 116 Toxic Gas Tenability........................................................................................................... 118 Visibility ............................................................................................................................. 122 Extinguishment ................................................................................................................... 123 SUMMARY OF FINDINGS AND CONCLUSIONS ............................................................... 124 Material Flammability Testing ............................................................................................... 124 Penetration Experiments ......................................................................................................... 124 Fire-hardening Experiments.................................................................................................... 125 Tenability Experiment ............................................................................................................ 126 RECOMMENDATIONS ............................................................................................................ 128 ACKNOWLEDGEMENTS ........................................................................................................ 129 REFERENCES ........................................................................................................................... 130 APPENDICES ............................................................................................................................ 132 Appendix A. Data Channel Description and Hook-up Lists..................................................