Glossary

A fire that spreads slowly across the forest floor or other low-lying vegetation. Although less intense than fast-moving fires, creeping fires can still reignite and expand if conditions change.

The leader of a team of firefighters responsible for managing their activities and ensuring their safety. The crew boss coordinates efforts during fire suppression and communicates with higher-level incident command.

An act that violates the law and is punishable by the state. In fire investigation, crimes can include arson, fraud, and negligence leading to a fire.

A formal accusation made by a governmental authority asserting that someone has committed a crime. In fire cases, this could involve charges of arson or criminal negligence.

An agreement between two or more parties to commit an unlawful act, such as planning and executing arson. Proof of conspiracy requires showing intent and an overt act toward committing the crime.

A formal written accusation submitted by a prosecutor alleging that a person has committed a crime. In fire-related cases, criminal information may include allegations of arson or fire code violations.

The mental state of an individual demonstrating their purpose to commit a specific criminal act. In arson cases, proving criminal intent is essential for establishing that a fire was set deliberately.

An act that is prohibited by law and punishable by fines, imprisonment, or both. Arson and related fire crimes fall under the category of criminal offenses.

The legal process in which a criminal case is heard and decided in a court of law. This may include arraignment, trial, and sentencing for fire-related offenses such as arson.

The act of bringing charges against an individual or organization in a court of law for committing a crime. In fire investigations, criminal prosecution may follow evidence that supports intentional ignition or negligence.

A written law enacted by a legislative body that defines what constitutes a crime and the penalties for committing it. Statutes related to fire crimes outline the legal framework for prosecuting arson and other offenses.

A fire that spreads rapidly through the upper canopy of trees. Crown fires are intense and can be difficult to control, often requiring aerial firefighting efforts.

The study and application of extremely low temperatures, often involving the liquefaction and storage of gases. While cryogenics is not typically related to common fire scenarios, certain industrial fires may involve cryogenic substances.

The formation of a concave or "cup-shaped" surface on wood as it dries or burns. This pattern can help investigators identify the direction and progression of a fire.

The process by which vegetation dries and loses moisture, making it more flammable. Curing is an important factor in determining fire risk, especially during dry seasons.

The flow of electric charge through a conductor, measured in amperes (amps). High current levels in electrical systems can create heat, leading to potential ignition sources in fire scenarios.

A component in batteries or electrical systems that facilitates the movement of electric current to and from the power source. Malfunctions in current collectors can contribute to overheating and fire risk.

The flow of electric charge through a conductor, which can generate heat. Electric current is a common ignition source in electrical fires when circuits are overloaded or damaged.

Vertical barriers installed near the ceiling of a building to control the movement of smoke and heat during a fire. Curtain boards help channel smoke towards exhaust systems and improve fire safety in large structures.

A fire that originates in the dashboard area of a vehicle, often due to electrical faults or overheating components. Dashboard fires can spread rapidly and pose risks to vehicle occupants.

The systematic examination and interpretation of data to extract useful information. In fire investigations, data analysis can include studying patterns of fire behavior, response times, and fire statistics.

A legal standard used in the U.S. to determine the admissibility of expert witness testimony based on scientific validity. In fire investigations, Daubert challenges may address the methods and reliability of fire origin and cause analysis.

Vegetation that is no longer alive and has lost its moisture content, making it highly flammable. Dead fuels contribute significantly to the intensity and spread of wildfires.

The remnants of destroyed materials left after a fire. Debris analysis can provide insights into the progression and intensity of a fire, as well as possible points of origin.

The act of burning waste materials, such as leaves, branches, or household refuse, often in outdoor settings. Improperly managed debris burning is a common cause of wildfires and requires safety measures to prevent fire spread.

A fire that originates in a pile of combustible debris. Debris fires can be accidental or intentional and may spread quickly if not controlled, posing a risk to surrounding structures and vegetation.

An explosion that results from the rapid decomposition of unstable chemical compounds, releasing large amounts of gas and energy. These explosions can occur in industrial settings or during chemical fires.

The energy released or absorbed during the chemical breakdown of a compound. This process can contribute to fire intensity, especially in cases involving volatile or reactive substances.

The logical process of drawing specific conclusions from general information. Fire investigators use deductive reasoning to analyze evidence and determine the most likely cause of a fire.

A buffer zone created around a building or structure to reduce fire risk by clearing or thinning vegetation and combustible materials. Defensible space is essential for protecting homes in wildfire-prone areas.

A type of combustion that propagates through a gas or along the surface of a combustible material at a speed less than the speed of sound. Deflagrations are characterized by rapid flame spread and can result in significant damage.

The process of carefully removing layers of debris or materials during a fire investigation to reveal underlying evidence or burn patterns. Delayering helps investigators analyze the fire's origin and progression.

The mass per unit volume of a substance, which affects how a material burns. Denser materials may burn more slowly, while less dense materials can ignite and spread fire more rapidly.

The act of positioning firefighting resources and personnel to effectively respond to and manage a fire incident. Deployment strategies are based on the fire's behavior, terrain, and available resources.

The formal process of taking sworn, out-of-court testimony from a witness as part of pre-trial discovery in legal proceedings. In fire investigations, depositions may be used to gather testimony from witnesses or experts.

The discovery and identification of fire at an early stage, which can be done using alarms, sensors, or visual observation. Early detection is crucial for effective fire suppression and minimizing damage.

An explosion in which the combustion process propagates through a medium at a speed greater than the speed of sound, producing a shock wave. Detonations are more destructive than deflagrations and can be associated with high explosives.

Devices used to initiate the detonation of an explosive material. They play a crucial role in controlled demolitions, mining, and certain industrial processes but can also be involved in criminal activities, including arson.

An explosion that occurs when a flammable gas or vapor mixes uniformly with air and ignites, resulting in a widespread and rapid combustion. Diffuse explosions are characterized by a broad area of effect and can cause significant damage.

Combustible material that is dispersed in the form of fine particles or vapors. Diffuse fuels, such as dust or gas, can create explosive environments when mixed with air and exposed to an ignition source.

A type of flame where the fuel and oxidizer are separate and mix at the flame front. Diffusion flames are common in open fires and tend to produce visible smoke and soot.

A firefighting strategy that involves directly applying water, foam, or other fire suppression agents to the burning edge of a fire. This method is effective for controlling small fires or portions of larger fires.

Evidence that directly proves a fact without the need for inference, such as eyewitness testimony or video footage. In fire investigations, direct evidence can help establish the cause and circumstances of a fire.

The legal process during which parties in a case exchange information and evidence before trial. Discovery can include documents, witness lists, and expert reports related to fire investigations.

The process of sending firefighting resources to the scene of a fire in response to an alarm or call for assistance. Dispatch centers coordinate the response and ensure the appropriate resources are mobilized efficiently.

A facility or location that receives emergency calls and coordinates the dispatching of firefighting resources, law enforcement, and medical services. Dispatch centers play a crucial role in ensuring timely and efficient responses to fire incidents.

A person responsible for managing communication between the public, emergency responders, and resources during fire or emergency incidents. Dispatchers handle the deployment of fire services and keep track of units on the scene.

A process used to separate components in a liquid mixture based on differences in boiling points. In fire investigations, distillation analysis can be used to identify accelerants or other flammable substances found at the scene.

A designated area within an incident response, often divided by geographical boundaries or responsibilities. Divisions help organize large-scale firefighting operations by assigning tasks and resources to specific sectors.

A heavy equipment vehicle equipped with a large blade, used to create firebreaks or clear vegetation and debris during firefighting operations. Dozers help prevent fire spread and provide access for ground crews.

A firebreak created by a bulldozer that clears away vegetation down to the soil, forming a barrier to slow or stop the spread of a fire. Dozer lines are an essential tool in wildfire management.

A handheld tool used to ignite controlled burns by dripping a flammable liquid mixture of diesel and gasoline onto the ground. Drip torches are used in backburning and prescribed fire operations to manage vegetation and reduce fuel loads.

The process in which burning materials from higher levels in a structure fall to lower levels, potentially igniting new fires or spreading an existing fire. Understanding drop down can help investigators trace fire progression in multi-story structures.

The designated area where aircraft release water or fire retardant during aerial firefighting operations. Drop zones are chosen strategically to maximize the effectiveness of the suppression effort.

A prolonged period of insufficient rainfall leading to dry conditions that increase fire risk. Droughts can result in dry vegetation that acts as fuel for wildfires and can create challenging firefighting conditions.

A measure used to assess the dryness of vegetation and soil, helping predict the likelihood of fire ignition and spread. Common indices include the Keetch-Byram Drought Index (KBDI), which helps guide firefighting strategies.

A non-pressurized pipe system installed near a water source, such as a pond or lake, to allow quick access to water for firefighting. Dry hydrants are used in rural or remote areas where traditional hydrant systems are unavailable.

A thunderstorm that produces lightning but little or no rainfall, increasing the risk of wildfire ignition. Dry lightning storms are common in arid regions and are a significant cause of wildfires.

A layer of decomposed organic material found on the forest floor that can ignite and smolder during a wildfire. Duff burns more slowly than other fuels but can retain heat and reignite fires after the main blaze has passed.

A rapid combustion event that occurs when a high concentration of combustible dust particles is suspended in the air and ignited. Dust explosions can happen in industrial settings, such as grain silos or factories.

A high-explosive material made from nitroglycerin and an absorbent substance, used in construction, demolition, and mining. Dynamite can be a potential hazard in fires if stored improperly or exposed to heat.

Protocols and safety measures used to prevent and manage fire risks associated with electric vehicle (EV) charging stations. These measures include proper installation, monitoring, and the use of fire suppression systems.

The specialized analysis of fire incidents involving electric vehicles. This type of investigation considers factors such as battery chemistry, charging systems, and electrical components to determine the cause and prevent future occurrences.

Built-in technologies and design elements in electric vehicles aimed at preventing fires and enhancing safety, such as thermal management systems, battery isolation units, and automatic shutoffs.

The study of interactions between living organisms and their environment. In fire science, ecology examines how fire affects ecosystems, including plant regeneration, animal habitats, and nutrient cycling.

A community of living organisms interacting with each other and their physical environment. Fire plays a natural role in many ecosystems, helping to clear dead material, promote new growth, and maintain biodiversity.

The range of temperatures at which a fire can ignite and sustain combustion. Understanding effective fire temperatures helps assess fire behavior and the potential for ignition under varying conditions.

A small, intense burst of electric current that can generate enough heat to ignite flammable materials. Sparks are common ignition sources in electrical fires.

A discharge of electric current that jumps across a gap between conductors, creating intense heat and light. Electrical arcing is a common ignition source for fires, especially in electrical equipment or wiring faults.

The release of electric energy as a spark or arc between two conductors. This discharge can generate significant heat and potentially ignite nearby combustible materials, contributing to electrical fires.

A fire that is started by electrical equipment or wiring. Electrical fires can result from short circuits, overloading, damaged insulation, or faulty appliances and pose unique risks due to live current.

Fires that involve electrical wiring, equipment, or devices. These types of fires often require specialized suppression techniques due to the risk of electrical shock and the nature of burning materials.

Non-conductive material used to prevent electric current from flowing where it is not intended, reducing the risk of shock or fire. Damaged or compromised insulation can lead to electrical arcing and fires.

A failure or irregular operation in an electrical system that can result in overheating, arcing, or short circuits. Electrical malfunctions are a common cause of fires in residential and commercial buildings.

A condition where electrical current exceeds the safe capacity of a circuit, causing overheating and potential fire hazards. Overloaded circuits can occur when too many devices are connected or when there is faulty wiring.

A fire that originates in an electrical panel due to wiring faults, overload, or equipment failure. Such fires can spread quickly and pose risks to entire electrical systems.

The examination of electrical panels for signs of wear, damage, or code violations to ensure safety and prevent fire risks. Regular inspections can detect potential problems before they lead to a fire.

The practice of maintaining and using electrical systems in a way that prevents hazards, including fires. Electrical safety involves proper installation, regular maintenance, and adherence to safety codes and standards.

A failure in an electrical circuit where current flows along an unintended path, often resulting in overheating or sparks. Short circuits can quickly ignite nearby flammable materials and lead to fire incidents.

The flow of electric charge, used as a power source for lighting, heating, and operating various devices. Improper handling or faults in electrical systems can lead to fire risks.

Chemical reactions that involve the transfer of electrons, often found in batteries and fuel cells. If these reactions are uncontrolled, they can generate excessive heat and potentially lead to a fire.

The deterioration of an electrode's material over time, affecting the performance of batteries and other electrical devices. Degraded electrodes can increase the risk of overheating and fire in battery-operated systems.

Chemicals added to the electrolyte in a battery to improve its performance and safety. While some additives can help prevent overheating, they must be carefully managed to avoid contributing to fire risks.

The escape of electrolyte fluid from a battery due to damage or faulty seals. Leakage can cause short circuits, corrosion, and increased risk of fire.

Digital data stored on electronic devices, such as computers and smartphones. In fire investigations, ESI can provide evidence regarding potential causes, timelines, and related communications.

A small, glowing piece of burning material that remains after a fire. Embers can travel long distances and ignite spot fires when they land on combustible surfaces.

The process of removing people from a dangerous area to a safer location during a fire or other emergency. Effective evacuation plans are essential for protecting lives in fire-prone environments.

The process of preparing for potential emergency situations, such as fires, by creating plans for response, evacuation, and communication. Proper emergency planning can reduce damage and save lives during fire incidents.

The actions taken by emergency personnel, such as firefighters and first responders, to address and manage fire incidents or other emergencies. This includes deploying resources, providing medical aid, and containing the fire.

A mechanism or switch used to quickly cut off power, fuel, or other systems in an emergency to prevent further damage or reduce fire risk. Emergency shutoffs are critical safety features in buildings and industrial sites.

An automated fire suppression system designed to activate when heat or smoke is detected, releasing water or other fire-suppressant materials. Emergency sprinklers are essential for controlling fires before they spread.

Information collected through observation or experimentation, rather than theory. In fire investigations, empirical data can include burn patterns, witness statements, and measured temperatures to support findings.

A chemical reaction that absorbs heat from its surroundings, which can lower the temperature and reduce the risk of fire. Endothermic materials may be used in fire suppression products to absorb heat.

The capacity to do work or produce heat. In the context of fire, energy is released through combustion, contributing to the spread and intensity of the fire.

The amount of energy stored in a given system or substance per unit volume or mass. In fire science, understanding energy density helps assess the potential for fuel sources to contribute to fire intensity.

An index used in wildfire behavior models that quantifies the potential energy available for release during combustion. Higher ERC values indicate greater fire potential and risk.

A fire apparatus or vehicle equipped to pump water and carry firefighting equipment. Engines are used for direct fire suppression, water supply, and supporting firefighting operations.

A brief, unintended explosion in an engine's exhaust or intake system. In fire investigations, an engine backfire may be considered as a potential ignition source.

A fire that starts in the engine bay of a vehicle due to fuel leaks, electrical malfunctions, or overheating. Engine compartment fires can spread quickly and require prompt attention.

A team of firefighters assigned to an engine who are responsible for operating the vehicle, pumping water, and conducting firefighting and suppression activities.