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Documenting Fire and Explosion Scenes with Leica ScanStation Technology. John D. DeHaan, Ph.D. Fire-Ex Forensics, Inc. Vallejo CA. Who Am I?. President and Principal: Fire-Ex Forensics, Inc.
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Documenting Fire and Explosion Scenes with Leica ScanStation Technology John D. DeHaan, Ph.D. Fire-Ex Forensics, Inc. Vallejo CA
Who Am I? • President and Principal: Fire-Ex Forensics, Inc. • Criminalist/Forensic scientist - involved in Fire & Explosion Investigations since 1971 (Lab, scene, research, publications) • Author, Kirk’s Fire Investigation (6 editions since 1983) • Co-Author, Forensic Fire Scene Reconstruction (with David Icove) • B.S. Physics, Univ. of Illinois at Chicago 1969 • Ph.D. in Pure & Applied Chemistry (forensic science), Univ. of Strathclyde, 1995
Use of Leica ScanStations • First exposed to scanning technology in 2002 while researching paper – (Interflam 2004) • Tested (via outsourced services) Leica, Reigl, and DeltaSphere for use inside fire scenes (2005-2008) • Retained Precision Simulations Inc. (Craig Fries) for scanning documentation of an accidental explosion scene and explosion tests using ScanStation • Collaborated with Leica on scanning documentation of full-scale fire tests (interior and exterior) using ScanStation C10
Laser Scanner Tests – Circa 2004 • 3D recreation of burned room using scanner limited by 3m minimum distance spec to closest object • Not well suited for small rooms Courtesy of Peter Tripi and Dan Livecchi, U.S. Secret Service; ATF FRL
Laser Scanner Tests – Circa 2004 Tried DeltaSphere IR Scanner before and after a post-flashover fire (single scan), but poor data capture on charred surfaces with this scanner
Fire Pattern Documentation Much better charred surface results with Leica ScanStation (circa 2009) Courtesy of Craig Fries (PSI) and Fire Cause Analysis
Applications of Scanning for Fire & Explosion Analysis • Capture physical dimensions for fire modeling • Scientific method requires full documentation • Dimensions of rooms, doors, windows • Debris field documentation for explosion scenes • Trajectories and distance • Research for explosion dynamics • Reconstruction of events from post-blast data
SketchingComputer-assisted, recreations of exterior view of fire-damaged structure Courtesy of Det. Mike Dalton, Knox County Sheriff’s Dept.
Fire Scene Documentation • SLOFIST
Outdoor Scene Cordoned Off Including All Vehicles! Rapid, accurate, complete measurements are critical
Documenting Post-Blast via 3D Laser Scanning Documenting Explosion Scenes: Rancho Cordova, 12/08
Documenting Post-Blast via 3D Laser Scanning Documenting Explosion Scenes: Rancho Cordova, 12/08
Debris in Yards and on Rooftops out to 150m Documenting Post-Blast via 3D Laser Scanning
Documenting Post-Blast via 3D Laser Scanning Heavy Fire Damage Inside Bathroom Wall was Key Evidence
Large Debris Field – Easily captured and identified with ScanStation C10 & software
Accurate, complete mapping of large scenes Rapid documentation of scenes Outdoors, day or night or indoors even at close range Conducted at same time as other scene activities Capture of multiple dimensions Ability to recreate 3-D image of scene Dimensions and trajectories captured quickly, saving investigator time Accuracy and comprehensiveness enhanced over manual methods Minimized exposure to hazardous environments Reduction in interruption of traffic or business Enabling better post-scene analysis of dynamics and indicators ScanStation Benefits & Advantagesfor Fire & Explosion Scenes
Thanks to: • Craig Fries, Precision Simulations Inc. • Tulare County Fire Investigators • Bureau of Alcohol, Tobacco & Firearms • Knox County Sherriff’s Office • Det. Mike Dalton, • Los Angeles County Sherriff’s Office • Dep. Rich Edwards, Retired • Tony Grissim, Leica Geosystems And, to you for attending!
