Analysis and Interpretation of Fire Scene Evidence (Methods in Analytical Toxicology)

• Introduces the techniques applied in the examination and interpretation of fire scene evidence• Details ASTM consensus standards• Compares the effectiveness of canines with that of emerging instrumental field tests• Provides guidance in the interpretation of analysis and highlights ways to generate the resulting reports• Summarizes recent developments in extraction and analysis that can be used to improve the detection of ILRs• Describes quality assurance methods in fire debris analysisOngoing advances in arson detection tools and techniques increase the importance of scientific evidence in related court proceedings. In order to assemble an airtight case, investigators and forensic scientists need a resource that assists them in properly conducting the chemical analysis and interpretation of physical evidence found at scenes of suspected arson.Analysis and Interpretation of Fire Scene Evidence introduces the techniques that determine the presence of ignitable liquid residues (ILRs) at fire scenes. It bridges the disciplines of investigation and forensic chemistry, enabling effective communication during critical periods of evidence detection, collection, packaging, and transport.The initial chapters are written from an investigator's perspective, allowing forensic specialists to understand fire dynamics, ignition, heat transfer, and investigations. Later chapters include a comparison of the use of canines versus new detection techniques, and an examination of laboratory facilities, equipment, and procedures that are essential to organizing a new lab or upgrading an existing one.By detailing the methods used to identify potential evidence at the scene of suspected arson fires, this volume also benefits attorneys and judges in preparing for prosecution and defense of arson cases. Analysis and Interpretation of Fire Scene Evidence 1 Preface 3 The Editors 5 Contributors 7 Table of Contents 8 Chapter 1: Fire Dynamics 10 1.1 What Did the Witness See? 10 1.2 Fire 12 1.2.1 Flame Types 13 1.2.2 Thermochemistry 13 1.2.3 Heat Release Rate 13 1.2.3.1 Measuring Heat Release Rate 17 1.2.3.2 Predicting Heat Release Rate 18 1.3 Enclosure Fires 19 1.4 Ignition 22 1.4.1 Gaseous Ignition 22 1.4.2 Liquid Ignition 24 1.4.3 Ignition of Solids 25 1.4.4 Flame Height 25 1.5 Fire Plume 27 1.6 Ceiling Jet 32 1.7 Heat Transfer 34 1.7.1 Radiation 34 1.7.2 Conduction 35 1.7.3 Convection 38 1.8 Smoke and Visibility 38 1.9 Recommended References 39 Notes 40 Chapter 2: Fire Scene Investigation: An Introduction for Chemists 42 2.1 Introduction 43 2.2 Fire Investigation Issues 43 2.2.2 What Is Arson? 44 2.2.3 The Role of the Fire Department 44 2.2.4 Why Investigate Fires? 45 2.2.5 Who Conducts Fire Scene Investigations? 46 2.2.6 Fire Investigator Certification Programs 47 2.2.7 Fire Scene Safety 48 2.2.8 Legal Considerations 53 2.2.9 Scientific Method 53 2.3 Fire Scene Examination 54 2.3.1 Witness Interviews 55 2.3.2 Exterior Fire Scene Examination 57 2.3.3 Interior Fire Scene Examination 59 2.3.4 Fire Patterns or Fire Indicators 65 2.3.4.1 V and Hourglass Patterns 66 2.3.4.2 Lines of Demarcation 68 2.3.4.3 Low Burns and Penetrations 70 2.3.4.4 Charring 70 2.3.4.5 Clean Burn 70 2.3.4.6 Trailers and Pour Patterns 72 2.3.4.7 Scene Documentation 73 2.3.5 Forensic Analysis 75 2.3.6 Fire Cause Classification 77 2.3.6.1 Accidental 77 2.3.6.2 Natural 78 2.3.6.3 Incendiary 78 2.4 Collection and Preservation of Evidence 78 2.4.1 Cross-Contamination Issues 79 2.4.2 Collection Procedures 80 2.5 Summary 82 References 83 Chapter 3: Detection of Ignitable Liquid Residues in Fire Scenes: Accelerant Detection Canine (ADC) Teams and Other Field Tests 84 3.1 Introduction 84 3.2 Visual Inspection of Fire Scene 85 3.3 Accelerant Detection Canines (ADC) 87 3.4 Instrumental Field Tests 92 3.5 Comparison of Techniques 98 3.6 The Future 102 References 103 Chapter 4: Essential Tools for the Analytical Laboratory: Facilities, Equipment, and Standard Operating Procedures 106 4.1 Facilities and Equipment 107 4.1.2 Key Factors 108 4.1.3 Technical 108 4.1.4 Discipline 109 4.1.5 Equipment 111 4.1.6 Instrumentation 111 4.1.7 Hazardous Materials 113 4.1.8 Evidence Flow and Security 115 4.1.9 Personnel 116 4.1.10 Safety 116 4.1.11 Adaptability 116 4.2 Sample Analysis 117 4.2.2 Sample Preparation 117 4.2.3 Techniques 118 4.2.4 Fume Hoods (All Methods) 119 4.2.5 Heat Sources (E1385, E1388, E1412, E1413, and E2154) 120 4.2.6 Adsorbents 121 4.2.7 Desorption 123 4.2.8 Standards 125 4.2.9 Miscellaneous 127 4.2.10 Analysis of the Sample 128 4.2.11 The Nature of the Analyte 128 4.2.12 Historical Notes 129 4.2.13 Chromatography 130 4.2.14 Detectors 131 4.2.15 Alternative Methods 134 4.3 Standard Operating Procedures 135 4.3.1 Historical Development 136 4.3.2 Congress and the National Bureau of Standards 136 4.3.3 The International Association of Arson Investigators 137 4.3.4 American Society for Testing and Materials 138 4.3.5 Technical Working Group for Fire and Explosions 139 4.3.6 The Need for Standard Operating Procedures 140 4.3.7 Minimum Standards 141 References 142 Chapter 5: Analytical Methods for the Detection and Characterization of Ignitable Liquid Residues from Fire Debris 145 5.1 Introduction 146 5.2 Gas Chromatography 146 5.2.1 Column Selection 147 5.2.2 Temperature Conditions 147 5.2.3 GC Detectors 148 5.2.4 Pattern Recognition 148 5.3 Gas Chromatography/Mass Spectrometry 150 5.3.1 Fundamental Theory of Mass Spectrometry 151 5.3.2 Fragmentation of Classes of Compounds Significant to Fire Debris Analysis 154 5.4 Approaches to GC/MS Data Analysis 157 5.4.1 Target Compound Chromatography 158 5.4.2 Extracted Ion Profiling 159 5.4.3 Library Searches 164 5.4.4 Summary 165 5.5 Criteria for Identification of Ignitable Liquids and Their Residues 165 5.5.1 Gasoline 166 5.5.2 Distillates and Dearomatized Distillates 166 5.5.3 Isoparaffinic Products, Normal Alkane Products, and Aromatic Products 168 5.5.4 Naphthenic/Paraffinic Products 169 5.5.5 Oxygenated Products 169 5.5.6 Summary 170 5.6 Recent Advances in Instrumental Techniques 170 5.7 Conclusion 171 References 171 Chapter 6: ASTM Approach to Fire Debris Analysis 173 6.1 Introduction 174 6.2 Evidence Handling Standards 176 6.2.1 ASTM E1492-90 (Reapproved 1999) Standard Practice for Receiving, Documenting, Storing, and Retrieving Evidence in a Forensic Science Laboratory 176 6.2.2 ASTM E1459-92 Standard Guide for Physical Evidence Labeling and Related Documentation 176 6.3 Standard Practices for the Separation of Ignitable Liquid Residues from Fire Debris 176 6.3.1 ASTM E1412-00 Standard Practice for Separation of Ignitable Liquid Residues from Fire Debris Samples by Passive Headspace Concentration with Activated Charcoal 177 6.3.2 ASTM E1413-00 Standard Practice for Separation of Ignitable Liquid Residues from Fire Debris Samples by Dynamic Headspace Concentration 182 6.3.3 ASTM 1388-00 Standard Practice for Sampling of Headspace Vapors from Fire Debris Samples 184 6.3.4 ASTM E1386-00 Standard Practice for Separation and Concentration of Ignitable Liquid Residues from Fire Debris Samples by Solvent Extraction 185 6.3.5 ASTM E2154-01 Standard Practice for Separation and Concentration of Ignitable Liquid Residues from Fire Debris Samples by Passive Headspace Concentration with Solid Phase Microextraction (SPME) 187 6.3.6 ASTM E1385-00 Standard Practice for Separation and Concentration of Ignitable Liquid Residues from Fire Debris Samples by Steam Distillation 189 6.4 Standard Test Methods for the Analysis of Ignitable Liquid Residues in Extracts 190 6.4.1 ASTM E1387-01 Standard Test Method for Ignitable Liquid Residues in Extracts from Fire Debris Samples by Gas Chromatography 191 6.4.2 ASTM E1618-01 Standard Test Method for Ignitable Liquid Residues in Extracts from Fire Debris Samples by Gas Chromatography-Mass Spectrometry 192 6.5 ASTM Ignitable Liquid Classification 193 6.6 Conclusion 197 References 197 Chapter 7: The Interpretation of Data Generated from Fire Debris Examination: Report Writing and Testimony 200 7.1 Interpretation 200 7.2 Reports 206 7.2.1 Case Folder 208 7.2.2 Archival 213 7.3 Definitions 214 7.4 Additional Background 227 7.5 Testimony 227 7.6 Spelling List 234 Chapter 8: New Developments and Quality Assurance in Fire Debris Analysis 235 8.1 Introduction 235 8.2 New Developments in Extraction Methods 236 8.3 Matrix and Background Considerations in Fire Debris Evidence 247 8.4 New Developments in Analytical Methods 248 8.5 New Developments in Data Analysis 254 8.6 Quality Assurance 255 8.7 Conclusions 256 References 256 Ongoing advances in arson detection tools and techniques increase the importance of scientific evidence in related court proceedings. In order to assemble an airtight case, investigators and forensic scientists need a resource that assists them in properly conducting the chemical analysis and interpretation of physical evidence found at scenes of suspected arson. Analysis and Interpretation of Fire Scene Evidence introduces the techniques that determine the presence of ignitable liquid residues (ILRs) at fire scenes. It bridges the disciplines of investigation and forensic chemistry, enabling effective communication during critical periods of evidence detection, collection, packaging, and transport. The initial chapters are written from an investigator's perspective, allowing forensic specialists to understand fire dynamics, ignition, heat transfer, and investigations. Later chapters include a comparison of the use of canines versus new detection techniques, and an examination of laboratory facilities, equipment, and procedures that are essential to organizing a new lab or upgrading an existing one. By detailing the methods used to identify potential evidence at the scene of suspected arson fires, this volume also benefits attorneys and judges in preparing for prosecution and defense of arson cases.