THE ARCHEOLOGY OF FIRE INVESTIGATION
FIRE INVESTIGATION
and
THE ALLURE OF archeology is as real to us as the gold and mummies in King Tut’s tomb, but we tend to think of the objects studied by archeologists as being remote and far away. Although we may picture archeologists as pithhelmeted figures in deserts digging through mountains of sand, as fire investigators we are actually involved in many of the methodologies and practices of archeology ourselves.
Fire has always figured prominently in the science of archeology. Civilizations or individuals subjected to fire leave behind the evidence of living: cooking artifacts, toys, jewelry, clothing, games, books, furniture, and coins. Burned, buried, and sodden from the ravages of fire, water, and earth, these remains may be worthless in terms of utility but priceless in terms of historical significance. The archeologist is the investigator who has unearthed it for us.
There’s evidence to be found, too, at the site of more recent fires-evidence identifying an object, incident, individual, or combination thereof as the initiator of a chain of events that resulted in the fire itself, in the manner and course of burning, fire creates paths and patterns that afterward become evidence of what has occurred.
Let’s step back for a moment to see if parallels ean be drawn between archeology and the science of fire investigation. The definition of archeology, according to the American College dictionary, is “the scientific study of any prehistoric culture by excavation and description of its remains.” Interestingly, if we just change two words in that definition, we have a pretty accurate description of how to go about analyzing a difficult fire: “the scientific study of any fire scene by excavation and description of its remains.” The similarities of how the archeologist and the fire investigator go about excavating and describing various remains is illuminating and educational. tion, “What happened”-what is the cause and origin of this fire-are unascertained.
Archeology is a science very closely related to what fire investigators do. As with other specialties from which we borrow, our first task is to learn as much as we can about it and then adapt that knowledge to our particular area of expertise.
The archeologist often has to dig through centuries of shifting sands, cities buried by the rubble and devastation of war, or civilizations frozen in time because of an erupting volcano. His study is to unearth the remote, both in time and space. He deals with the distant past, the deeply buried. As fire investigators, we use the same tools as the archeologist. Our goal is to unearth secrets carefully without disturbing or destroying the fragile bits of knowledge at the ends of our shovels. Unlike the archeologist, we almost always deal with the immediate past. We are often ready to dig through a collapsed building before the ashes are cold.
Both the archeologist and the fire investigator, with different purposes, are asking the same question. The archeologist’s purpose is fundamentally academic in orientation. He wants to gain knowledge to satisfy a yearning in his own soul, to increase the general body of knowledge, to answer some questions of historical significance, or to prove or disprove a theoretical point. The fire investigator’s purpose is forensic in nature, meaning belonging to or used in legal proceedings, be they criminal or civil.
Although these goals and motivations are indeed different, the question they both ask is this: What happened?
What happened 20 centuries ago during the Peloponnesian War?
What happened last month at the Roxie Theatre when a fire broke out in the projectionist’s booth?
What happened? There are a variety of subquestions that must be addressed before an accurate determination of what happened can be made:
Can what happened be discovered?
How do we go about uncovering the facts?
Can we do so without altering or disturbing the evidence?
What is involved in the procedure of excavation?
How do the objects that we excavate relate to the locations in which they are found?
What tools do we use?
How do we record the procedures, sequence, path, and pattern of our discoveries to document that they were not fraudulently obtained?
What do our discoveries mean? For the archeologist, what do they mean in terms of better understanding a chain of events? For the fire analyst, what do they mean in terms of better understanding this chain of events with an eye, where appropriate, to attributing blame (if arson), responsibility (if product liability), or neither (if accidental)?
CAN WHAT HAPPENED BE DISCOVERED?
It is necessary to ask this because time and energy are valuable commodities both to the archeologist, whose university or museum usually has a limited budget, and to the fire investigator or fire marshal, whose municipality or the insurance company for which he works often has a very tight rein on expenditures.
For the archeologist financially equipped to dig for remains, that answer is usually yes-if he is reasonably certain that he is in the right location.
For the fire investigator, that answer is often related to the condition of a structure upon his arrival. We have all responded to fires so devastating that the entire edifice, or even a series of connected buildings, has collapsed. At some, heavy equipment such as a bulldozer may have been used to dissipate the smoldering remains. In such cases, the answer is usually “No, what happened cannot be discovered.” As fire investigators, the likelihood of an undisturbed or “readable” origin of fire is so limited that time and money would be wasted. In circumstances such as these, our jobs are over before they havebegun. Our findings relative to the quesTHE ARCHEOLOGY OF FIRE INVESTIGATION
Assuming, however, that the fire damage and/or damage from firefighting operations was not so severe as to make discovery of the facts of the fire impossible, then we go on to the next question.
HOW DO WE GO ABOUT DISCOVERING THE FACTS?
The basis of scientific archeological excavation is to observe accurately and carefully record a strateographic profile. That is, archeologists proceed layer by layer through and to their findings. Fire investigators at a fire scene also proceed in this manner. Layer by layer, we observe, identify, and uncover the various objects and patterns to form an idea of their relationship to the total picture.
Although it is our job to do the always delicate and sometimes tedious task of documenting, uncovering, and preserving evidence, some fire investigators attack a fire scene as if they were strip miners using earthmovers to speed the process along. Such clumsy enthusiasm denies the investigator the opportunity to reconstruct an “undisturbed site.”
At first glance, the burn site may resemble charred pick-up sticks piled haphazardly. The more devastating the fire, the more unrecognizable the debris. With careful observation, awareness of building construction, and the knowledge of how fire travels, however, the scene will begin to unfold Like an archeologist, we fit together a complicated collection of clues that give a general impression and explanation of what happened before and during the fire, to arrive at the point of origin and hopefully, the cause of the fire.
In most cases, before we have even arrived at the burn site we know the burn time, the construction of the building, the description of the premises, the method of extinguishment, the path of the fire, the temperature of various combustibles, the fire load, evidence of charring both in depth and in location, and many other indicators. Our ability to interpret the burn pattern is a total of all the knowledge and experience we bring to the site and all of the data we acquire there.
CAN WE DISCOVER THE FACTS WITHOUT ALTERING, DISTURBING, OR DESTROYING THE EVIDENCE IN THE PROCESS?
The science of archeology involves recovery of data from the soil using an assortment of skills: accurate recording, precise excavation, detailed laboratory analysis, and knowledgeable interpretation of the acquired information. The fire investigator also has the burden of carefully acquiring and interpreting data, but because of the nature of our job, we call our data “evidence.” The tasks are similar, but our job is easier. For us, the evidence is still basically uncontaminated; our clues are fresh; and the nature and purpose of our artifacts can usually be easily recognized.
The fire debris must be sifted through, layer by layer, in the course of our analysis, taking into consideration all of the variables mentioned above. The debris we handle has a relationship to what happened before, during, and after the fire. It is the archeologist’s job to reconstruct a site. We do this all the time as fire investigators, whether physically or mentally. Layer by layer, the facts unfold.
In describing the similarities of the two disciplines, we don’t mean to imply that every fire scene is a painstaking archeological dig. Some fire scenes are obvious, with the cause and point of origin as glaring as a “V” pattern pointing to a greasy frying pan sitting on an unattended hot gas stove. Other fire scenes (particularly when dealing with a collapse) require that we apply all of the principles of archeology as well as those of fire investigation. When we suspect that a fire has been set intentionally and that we have an arsonist on the loose, it is our responsibility to be as meticulous as possible.
Although it is often impossible to gain access to a building after a collapse, we investigated a fire in which we were able to dig through rooms of rubble. We were invited to work with an excellent fire department whose personnel-everyone from the chief fire marshal to the captain and lieutenant who had fought the fire-were interested in assisting in any way possible. From this fire, we truly experienced the joy of discovery that must have fallen to the archeologist digging through a pyramid who finally finds his cache of gold.
The fire was in a large delicatessen/ restaurant in New England. We arrived to find the exterior walls of the buildings, as well as parts of the first floor interior adjacent to the exterior walls, relatively intact. But the entire center of the building had collapsed, and only a few random beams kept the rest of the debris from falling into the basement. Fortunately, there were still undisturbed pockets underneath the first floor.
Our first job was to pump out the thousands of gallons of water that had flooded the basement during the firefighting operations. Then, assisted by cranes and other heavy equipment, we managed to open up a path into one of the undisturbed pockets in the basement. Once below, we were able to thread our way carefully from pocket to pocket, photographing and examining the debris as we went along.
It was not until our fourth day at the fire scene that we reached a remote area in the front corner of the restaurant barely accessible through the collapsed beams. Here we discovered a wooden table pushed up against the wall. On the top of that table was the clearest and most easily identifiable flammable liquid burn pattern, with a classic “V” pattern emanating from it up the wall.
Our goal as fire investigators is to develop scientific procedures to assist us in analyzing burn sites, as opposed to embarking on haphazard digs. We are archeologists of char. We dig and we displace matter, as do our academic counterparts. And we must do so with great care, method, planning, and design.
WHAT IS INVOLVED IN THE PROCEDURE OF EXCAVATION?
As in archeology, our analysis of a fire scene can be a vertical and/or a horizontal excavation.
Vertical excavation is selective digging, uncovering a limited area for the purpose of recovering specific information. We might locate the south wall of the master bedroom as the area of origin. Photographing and removing obstacles as we move closer to the cause, we might eventually discover that the fire originated in a short circuit in the electrical wiring in the wall. This is the type of excavation that most of us do.
Horizontal or area excavation is done on a larger scale. It is as close to a total excavation as we can get. Many times this method has to be used on an entire building, as in the case of the restaurant collapse. It was necessary to strip off top layers which did not bear any relevance to the cause of the fire in order to reveal the subsurface in which we were interested.
HOW DO THESE OBJECTS RELATE TO THE LOCATIONS IN WHICH THEY ARE FOUND?
The associations that are made by archeologists are fundamentally logical: Stone, axes, and bones of extinct animals discovered in the same geological layers are normally considered to be associated with each other.
Because of the catastrophic nature of fire, however, our investigations often uncover objects at the same layer or in the same locations that common sense tells us cannot have originated there: roofing material in the cellar, a bath tub hanging through the ceiling, etc.
With the exception of these dislocated objects, though, it holds true for fire investigation as it does for archeology that objects or incidents found in association with each other-in the same area-are related. Take, for example, the logical manner in which fire always burns up and out, and the related burn patterns that we discover on the baseboards, which move logically up the wall, along the ceiling beams, through the cockloft, and out the roof.
WHAT TOOLS DO WE USE?
Excavation, whether performed on a grand scale (at a building collapse) or a small scale (on a kitchen countertop, for instance) always requires tools.
At a collapse site, backhoes and earthmoving equipment are often utilized. This equipment must be supervised at all times during the course of a fire investigation. Construction workers and building demolition crews are not aware of our need to examine the undisturbed layers of charred material. Just recently, we witnessed the excavation of a burned building during which a clam bucket removed a body, forever destroying its position and location, and the circumstances of the death. Such misuse of heavy equipment is unnecessary and destructive.
Photo 1
Photo 2
Photo 3
As we get close to the area of origin, spades, shovels, picks, and other small hand tools are used for loosening and moving large sections of debris. In many cases, screens and paint brushes should be brought in to sift and clear for smaller articles. Brushes are extremely useful tools, especially in revealing fine char and cleaning an area so that charring can be seen without disturbing the char. Interestingly, these are the very same tools that one might find at the excavation site of a pyramid or an ancient min.
THE ARCHEOLOGY OF FIRE INVESTIGATION
While investigating a fire in Minnesota during – 30° weather, we wanted to dust off an area inaccessible to a brush in order to look at a section of the wall for burn patterns. We obviously couldn’t use water, which would have instantly froze. So we went to a local camera store and bought two cans of compressed air, which is used in cleaning cameras. We used it to blow away the fire char, enabling us to examine the wood. This did the trick without altering or destroying the evidence.
Using water to clear away debris can also clear away the residue that you might have wanted to send to a laboratory for a sample. An old saying warns us not to throw out the baby with the bath water, and it should be remembered whenever we go to a burn site.
HOW DO WE RECORD THE PROCEDURES, SEQUENCES, PATHS AND PATTERNS OF OUR FINDINGS?
As fire investigators, we have at our disposal many of the tools and methods of archeology, and like that more academic science, our purpose is not just to discover facts, but also to be able to communicate what we have discovered.
There is a term in archeology’ called “in situ,” meaning “in its original place.” Everything from Pharaoh’s bones to flammable rags should be photographed “in situ” before anything is physically examined or moved. This serves not only to establish and determine accurate representation of historical facts, but it is also an excellent way to cover yourself in the event someone’s out to discredit your findings.
In both sciences, though, it is essential that the archeologist and the fire investigator remember that the process of excavating is a process of rearranging, and that prior to doing any alterations of any kind, the site must be documented by drawings and photographs. Aside from preserving the integrity of our observations in this objective manner, we are also protecting ourselves from any allegations of mishandling or mismanaging the evidence.
A fire marshal was once accused of faking evidence during a highly publicized arson/homicide investigation. The marshal had determined that the fire was incendiary in nature, and reported that he had found rags and a lighter fluid can on an oil drum at the scene. He had fully photographed and documented these items where, when, and as he found them, and photographically documented the scene after the items had been removed for laboratory analysis. An attorney out to discredit his findings reversed the order of the marshal’s photographs in an attempt to indicate that the rags and lighter fluid had been placed on the oil drum instead of having been removed from it. The marshal kept accurate records, however. He had retained his film negatives and was able to prove that the attorney had reversed the sequence of photographs.
Both in the service of truth and in the service of the agencies that employ us, how we go about our jobs as investigators is directly related to the questions we pose to ourselves at a fire scene, and our commitment to finding answers.
WHAT DO OUR DISCOVERIES MEAN?
Well, we are not going to prove or disprove such grand theories as whether or not the Dead Sea actually parted, or if there really was a Helen of Troy. But our dedication to a job well done can put an arsonist in jail or keep an innocent man falsely accused out of jail. We can let parents know that their disturbed child plays with matches and that he needs help. We can determine that a poorly designed product overheated or that a product accused of faulty design was nowhere near the origin of the fire. We can alert the public to types of fire emanating from dangerous people, dangerous objects, or dangerous habits.
Archeology deals with the past, but by using the tools of archeology in our fire science, we can positively affect the future, get a tremendous amount of pleasure of our process of discovery, and save lives.
