As Fire Investigators, our thought process and investigative methodology employs us to both mentally and physically reconstruct the scene to a pre-incident state for data collection analysis and hypothesis development.
The successful development and composition of a forensic fire scene sketch or diagram is a critical component of the detailed scene documentation process.
While not every scene may command the creation of comprehensive sketches or diagrams, even a simplistic recreation can benefit the investigative process on smaller scale incidents.
A high-level artistic skill set is not required to create an adequate representation of the scene.
Artistic tools such as geometric drawing templets, scene object stencils, graph paper, perspective paper, engineering rulers and protractors can aid in the quick novice composition.
Measuring tools such as tape measures, measuring wheels and laser distance meters can assist with the collection of necessary dimensions.
Keeping your investigation unit well equipped with clip boards, sharpened pencils, erasers, and small drawing lights can ensure that preparedness is not an obstacle.
N.F.P.A 921 cautions us in 16.4.1 by stating, “Fire Investigations that can be reasonably expected to be involved in criminal or civil litigation should be sketched or diagrammed.” While forecasting the legal future of a fire scene investigation is sometimes difficult, the composition of a quick artistic recreation may serve to benefit in less detailed examinations.
Section 16.4 also reminds us that, no matter how professional a diagram may appear, it is only as useful as the accuracy of the data used in its creation.
Accurate sketches and diagrams can assist the investigator in documenting evidence of fire growth, scene conditions, and other details of the fire scene.
Fire scene sketches and diagrams are often broken down into two main categories, two dimensional and three dimensional.
N.F.P.A 16.4.1.1 states that sketches can be either three-dimensional or two-dimensional representations.
However, referring to sketches and diagrams as three-dimensional is an incorrect designation.
Some examples of true three-dimensional artwork are sculptures, and carvings.
Sketches and diagrams that have a threedimensional appearance should be correctly referred to as two-dimensional perspective drawings creating an illusion of space and depth on a two-dimensional flat surface.
For purposes of this article, I will refer to these artistic representations as two-dimensional perspective sketches or diagrams (3D appearance).
The scene sketch is a freehand forensic artistic representation of the fire scene, developed while on location and in conjunction with the full-scale fire investigation process.
Many different types of sketches are useful in creating an artistic fire scene recreation.
Some of the most common types of sketches often used are discussed below.
An artistic view of the affected compartment including dead load and live load components represented as shapes, depicting length and width but not depth and perspective.
Two-dimensional sketches can include floor plan sketches, site plan sketches, and exploded view sketches.
An artistic bird’s eye view of the affected space, building, or compartment.
These types of forensic sketches are two dimensional and often include architectural features such as doorways with swing direction, window openings, porches and sunrooms and other key components.
Utilities may also be included along with live load components such as furniture.
Approximate measurements, and dimensions of the compartments and overall structure should be considered for inclusion when necessary.
An artistic bird’s eye view of the affected area, property, or lot.
These types of forensic sketches are two dimensional and often include architectural features, accessory structures, geographical and natural features (streams, ponds etc.), and impervious ground coverings such as patios and driveways.
Approximate measurements, dimensions, and any other relevant objects present on the scene should also be considered for inclusion when necessary.
An artistic bird’s eye view of the affected space, building, or compartment.
These types of sketches are two dimensional and often include architectural features, approximate measurements, and dimensions.
All walls and or surfaces within the compartment are depicted within these representations.
An artistic view of the affected compartment providing realistic views including dead load and live load components, depicting length, width, and creating an illusion of space and depth on a two-dimensional flat drawing surface.
Structural dead load components and features including walls, doorways, windows and built in furniture can be realistically represented to create a pre-incident overview.
Occupant interviews and partial remains can assist in the placement and addition of live load components to create a full-scale pre-incident composition.
The creation of a freehand scene sketch often takes place after the photographic overview, preliminary investigation and basic scene overview is completed.
My preference is to develop the forensic fire scene sketch in my mind prior to occupant interviews and scene excavation.
Often, I will first develop a brief sketch, either a two-dimensional perspective sketch (3D appearance) or a floor plan sketch, of the structural elements within the potential room of origin.
During the initial occupant interview I will review the empty compartment sketch, which I refer to as the “dead load sketch,” with the occupant and ask them to explain the placement of live load components, such as furniture, lighting fixtures, electronics, extension cords, personal belongings, and any other relevant items.
I will then ask the occupant to identify the placement of electrical outlets and fixtures within the compartment.
Upon the completion of the compartment sketch I will review the layout as presented and described with any assisting investigators.
As the investigation progresses and scene excavation occurs, I will make notes as to the location of the documented items for consistency of location.
Upon competition of the comprehensive fire scene analysis, I will fine tune my rough sketch with any uncovered items or details that are applicable to the investigative process.
When applicable I will sometimes document areas of substantial damage, fire patterns or areas of high significance in the scene sketch.
Scene sketches, similar to fire scene notes, should be permanently maintained with the investigative file.
Similar to sketches, the diagram is a freehand forensic artistic representation of the fire scene.
Diagrams differ from sketches in that they are often developed back at the station or office, after the full-scale fire investigation process has been completed.
These artistic compositions are usually developed with a greater level of detail and finish, often including line detail, shading, crosshatching, and blending.
A greater degree of time and effort resulting in a polished piece with an accuracy for capturing fine detail is sure to complement the fire investigation process.
Imagine you are a juror, and you are presented with the fire scene photograph.
You have never been to a fire scene, never viewed a burned-out room, and never experienced the devastating effects of a compartment fire in person, yet you are asked to review this photo in the course of your decision making process.
The photo is chaotic and represents a blur of destruction and loss.
The remains of objects and structural features are unidentifiable.
A diagram is now presented to you and provides clarity of the pre-incident layout.
The charred remains of objects in the first picture now start to make sense.
You can now conceptually visualize the room in its original state, and easily follow the investigative process explained in the proceedings.
The simple development of a scene diagram now becomes an integral piece of the case.
The detailed documentation of the wildland fire investigation scene can be a difficult task.
The forest floor, covered with brush, leaves, and plant material cannot always be captured and interpreted accurately through photographs.
There are challenges with lighting and shadows which can cause distorted images with exposure issues creating an unclear photo.
Scene sketches and diagrams for these types of investigations can provide a detailed overview of observed patterns and affected areas to complement scene photographs.
The inclusion of flags or markers indicating areas of significant interest can also be helpful.
Detailed expansion sketches can be included into the diagram as well to draw attention to specific items or areas.
Although the sketch artist can become easily overwhelmed with attempting to capture the wildland scene in its total observed state with incredible detail, this is not always necessary.
Sole concentration on significant and relevant natural features such as larger trees, rocks, bushes, and plants can help make the scope of documentation more manageable.
These significant features should be included into the sketch or diagram to show proximity and relevance while less important ground debris and vegetation surrounding the general origin area can be omitted.
Differential shading techniques can also be utilized to depict boundaries of burned areas.
The inclusion of GPS coordinates into the informational section of the sketch or diagram can provide a more detailed location for future reference.
These artistic overviews can provide significant value to the wildland investigative procedure.
The informational section on a sketch or diagram can vary in its contents depending on the situation, however there are certain staples that should always be included.
Name, rank, date, address, and case number should always be present on the composition.
Items such as GPS coordinates, Legend for symbol designation, and compass orientation are situationally dependent.
Unless drawn to scale, the phrase “Not to scale” should always appear on the piece.
Do not let your artistic ability or lack thereof prevent you from attempting a composition.
Practice on rooms and objects within your home or station and use drawing aids to help perfect your skill.
