The Johnson County Sheriff’s Office Criminalistics Laboratory has used laser scanning since 2011, when the crime lab purchased a ScanStation C10. In 2017, the lab added a ScanStation PS40 to their equipment profile to enhance their ability to capture crime scenes. In their first year of deploying the PS40, they had an opportunity to scan this fire scene in which extensive damage was caused to an apartment complex. In a typical fire scene, everything becomes soot-covered and blackened from the fire and smoke damage, and the burned and blackened surfaces are often difficult to visualize. In this video, you can see that colors from the scanner images were applied to the outdoor scene where the colors were abundant. The scans inside the fire scene were captured without images, and they are displayed here in grayscale intensity mapping.
The ScanStation laser uses two different wavelength components, one 658 nm and one 1550 nm. These wavelengths allow the laser to “see” in infrared. Much like the older technique of using infrared film photography, the ScanStation allows for real-time, on-site feedback from the intensity mapping of the data. This allows the investigator to discern surfaces that have sustained varying levels of damage from direct flames, burning, and exposure to high heat, soot, and smoke.
The flythrough first moves into a second-floor apartment that sustained damage, but most of the contents and arrangement of the apartment are still evident. The video then moves downward into the ground floor, where more substantial damage occurred. Fire damage is evident in the widespread debris and walls that have been burned down to the metal pre-fab studs. The ScanStation allowed investigators to gather crucial interpretive information at the scene and to scan the entire site quickly and safely.
To learn more about how laser scanning could benefit your agency, please contact us.