Glossary

A substance that can spontaneously ignite when exposed to air due to its highly reactive nature. Examples include certain metals and chemical compounds used in industry.

A burn injury caused by exposure to intense radiant heat from a fire or hot object without direct contact. Radiant burns can occur at significant distances from the heat source.

Heat energy that is transferred through electromagnetic waves from a hot surface or flame to surrounding objects. Radiant heat can ignite nearby flammable materials and cause severe damage.

The rate of heat energy emitted per unit area from a radiating source. High radiant heat flux can lead to ignition of flammable materials and contribute to fire spread.

The transfer of heat energy through electromagnetic waves without the need for direct contact. Radiation is one of the primary ways fires spread heat to surrounding objects and materials.

The process of quickly recharging batteries at a high current, which can lead to overheating if not properly managed. Rapid charging poses a fire risk, especially with lithium-ion batteries.

A technique used by firefighters to descend steep or vertical surfaces with the aid of ropes and harnesses. Rappelling is often employed in rugged terrain to access areas affected by wildfires.

The speed at which a fire moves across a surface or through vegetation, typically measured in chains or meters per hour. The rate of spread helps fire managers assess fire behavior and develop suppression tactics.

The process where a previously burned area reignites and burns again, often due to remaining fuel that was not consumed during the initial fire. Reburns can occur when conditions become favorable for ignition.

A certification card issued to wildland firefighters indicating that they have met the training and physical fitness requirements to engage in firefighting activities. The Red Card ensures that personnel are qualified for wildfire assignments.

A weather alert issued by meteorological agencies when conditions such as high winds, low humidity, and dry fuels create a high potential for rapid fire spread. Red flag warnings help fire managers and the public prepare for increased fire risk.

Areas identified as high risk for wildfire due to factors like dense vegetation, dry conditions, and proximity to populated areas. These zones require heightened fire prevention and response efforts.

The process of restoring land and infrastructure after a fire has been contained. Rehabilitation efforts include stabilizing soil, replanting vegetation, and repairing damage to minimize environmental and structural impacts.

The re-ignition of a fire that was previously extinguished, often due to smoldering embers or hotspots that were not completely suppressed. Preventing rekindles is a key focus during the overhaul phase of firefighting.

The amount of moisture in the air relative to the maximum amount of moisture the air can hold at a given temperature. Low relative humidity can increase fire risk by drying out fuels and making them more flammable.

A weather monitoring station that provides real-time data on temperature, humidity, wind speed, and other factors that influence fire behavior. RAWS units are critical for fire prediction and management.

Specialized boats and vessels equipped for fire suppression and rescue operations on water. These craft are used to combat fires on ships, docks, and waterfront properties.

A strategic document that outlines the use and conservation of natural resources, including fire management practices. RMPs help land managers balance environmental health with fire risk reduction.

A formal request for specific resources, such as equipment, personnel, or aircraft, during a fire response. Resource orders ensure that firefighting efforts are well-supported and coordinated.

The personnel, equipment, and tools used in firefighting operations. Effective use of resources is essential for successful fire suppression and control.

The obligation to take preventive measures and respond to fire incidents in accordance with established guidelines. Responsibility can apply to individuals, organizations, or governing bodies in fire management.

A chemical substance applied to vegetation or structures to slow the spread of fire. Fire retardants are used in aerial firefighting operations and ground-based fire prevention strategies.

The legal authorization for fire investigators, firefighters, or emergency personnel to enter a property to suppress a fire, conduct an investigation, or ensure safety compliance.

The likelihood of a fire occurring and the potential consequences associated with it. Risk assessment helps fire management teams develop strategies to reduce and manage fire hazards.

The process of identifying, assessing, and mitigating risks associated with fire incidents. Risk management strategies aim to minimize damage and enhance safety in communities and work environments.

The condition where hot gases and flames spread across a ceiling and roll out from the top of a compartment. Rollover is a precursor to flashover and indicates rapidly worsening fire conditions.

A period when a fire spreads rapidly over a significant distance due to favorable conditions such as wind and fuel availability. Runs can lead to sudden increases in fire size and intensity.

The movement of a fire in a continuous, fast-paced manner over a landscape. Running fires are difficult to control and can cover large areas quickly, posing significant threats to property and safety.

A designated area managed by a local fire department responsible for providing fire protection services to rural communities. These districts often rely on volunteer firefighters and may face unique challenges due to limited resources.

Fire prevention and suppression services provided to rural areas, often managed by volunteer fire departments or local fire districts. These services include wildfire response, structural fire protection, and public education.

Special Investigations Unit, a department within an insurance company or law enforcement agency that investigates suspicious claims or potential fraud. SIUs often collaborate with fire investigators in cases of suspected arson.

The deliberate act of damaging or interfering with equipment or processes to cause harm or disrupt operations. In fire investigations, sabotage may be considered if there is evidence of intentional tampering that led to a fire.

A burn pattern that forms on a ridge or saddle-shaped terrain, indicating how a fire moved over the topography. Saddle burns help investigators understand fire behavior in hilly or mountainous regions.

A switch designed to shut off power or fuel supply in an emergency to prevent overheating and reduce fire risk. Safety cutoff switches are commonly found in electrical and gas-powered equipment.

A thorough examination of buildings, equipment, or systems to identify potential fire hazards and ensure compliance with fire codes and safety standards. Safety inspections help prevent fires and improve overall safety.

Regular or periodic assessments conducted to identify and mitigate fire risks in facilities or properties. These inspections ensure that fire prevention measures and safety protocols are in place and functioning properly.

A set of procedures and practices established to protect individuals and property from fire hazards. Safety protocols are implemented in workplaces, residential areas, and during fire response operations to reduce risk and enhance safety.

Comprehensive guidelines followed by individuals or organizations to prevent fire incidents and ensure the safety of personnel. Safety protocols include evacuation plans, fire drills, and proper handling of flammable materials.

Instruction and practice provided to individuals to help them understand fire safety principles, use firefighting equipment, and respond effectively in emergencies. Safety training is essential for both firefighters and the general public.

A designated area where firefighters and personnel can seek refuge from a fire without the risk of injury or death. Safety zones are critical for ensuring the well-being of firefighting teams during wildfire operations.

A person or company involved in the recovery and preservation of property following a fire or disaster. Salvors may work with insurance companies to assess damage and determine the salvageable value of assets.

The location where a fire incident has occurred, which becomes the focus of investigation and response efforts. The scene is documented and analyzed to gather evidence, determine the cause, and assess damage.

The process of recording details and observations at a fire scene through photographs, sketches, and written reports. Documentation is essential for investigations, insurance claims, and legal proceedings.

The practice of protecting a fire scene from contamination, tampering, or destruction to ensure the integrity of evidence for investigation purposes. Proper scene preservation is vital for accurate fire analysis.

The ability of trained canines to differentiate between various scents at a fire scene, particularly to detect accelerants or specific chemicals. This skill is valuable in arson investigations.

A systematic approach used in fire investigations to collect data, form hypotheses, conduct experiments, and draw conclusions. The scientific method ensures that findings are objective and evidence-based.

A shallow, quickly constructed firebreak made by removing vegetation and debris to slow the advance of a fire. Scratch lines are often created by hand crews as an initial effort to control fire spread.

A systematic approach used by investigators to thoroughly examine a fire scene for evidence. Common search patterns include grid, spiral, and strip methods to ensure no area is overlooked.

The damage to the upholstery of seats caused by fire or heat exposure. The pattern and extent of these burns can help fire investigators understand fire behavior, intensity, and the direction of flames in vehicle or structural fires.

The exact location where an explosion originates, determined by analyzing blast damage, debris patterns, and other evidence. Identifying the seat of an explosion is crucial for understanding the cause and potential accelerants involved.

An explosion that has a defined point of origin and leaves evidence of a blast seat. This type of explosion is often contrasted with diffuse explosions, which do not have a clearly defined source.

An additional explosion that occurs after an initial explosion, often due to the ignition of unburned fuel or gases released in the first event. Secondary explosions can cause significant additional damage and pose dangers to responders.

Materials that are capable of stopping combustion on their own once the heat source is removed. These materials help prevent the spread of fire and are used in fire-resistant construction and products.

The process by which certain materials generate heat internally due to chemical reactions, oxidation, or biological activity. If not properly managed, self-heating can lead to spontaneous ignition.

The spontaneous ignition of a material without an external flame or spark, usually due to heat buildup from internal chemical reactions or friction. Self-ignition poses risks in environments with oily rags, compost, or certain chemicals.

The lowest temperature at which a material will ignite spontaneously without an external ignition source. Understanding this temperature is key for fire prevention and handling flammable materials.

The act of implicating oneself in a crime or admitting to actions that may result in legal consequences. In fire investigations, individuals may avoid self-incrimination by exercising their legal rights during questioning.

The malfunction of a battery or chemical separator that prevents contact between components such as electrodes. Separator failures can lead to short circuits and potential fires or explosions in battery systems.

An electrical discharge that occurs when a high-voltage connection is interrupted, creating a spark or arc. Server arcs can cause heat buildup and pose fire hazards in electrical systems.

Financial resources allocated to address extreme fire conditions, often used for additional personnel, equipment, or emergency response activities. Severity funding supports proactive measures during peak fire seasons.

An unintended path of electrical current that bypasses the normal circuit, causing a surge in current flow. Short circuits can generate heat, leading to electrical fires and damage to connected devices.

An individual piece of equipment or person assigned to a firefighting task, such as an engine or a firefighter. Single resources are deployed to specific tasks or areas as part of larger fire response operations.

The location where a fire incident has occurred or is being investigated. The site may be a structure, vehicle, or open area and is crucial for evidence collection and analysis.

The initial assessment conducted by first responders or fire commanders to evaluate the situation, identify potential hazards, and plan an effective response. Size-up is essential for determining strategies and allocating resources during a fire incident.

Debris from forestry operations, including branches, twigs, and cut vegetation, which can contribute to fire risk if not properly managed. Slash is often reduced or removed to prevent wildfires.

The protective covering applied to electrical wires and cables to insulate them and prevent heat transfer. Damaged or inadequate sleeving can increase the risk of electrical fires.

Cargo carried beneath a helicopter for delivery to remote or hard-to-reach fire locations. Sling loads may include firefighting supplies, water, or equipment and play a vital role in wildfire response.

The situation when a fire crosses a control line or firebreak, often due to wind, ember spotting, or changes in fire behavior. Slop-overs require immediate attention to prevent further spread.

The angle or gradient of the land, which affects fire behavior and spread. Fires tend to move more rapidly uphill due to the preheating of vegetation above the fire.

A mixture of gases, vapor, and particulate matter produced by the combustion of materials. Smoke can contain toxic compounds and reduce visibility, posing health risks and challenges for firefighting efforts.

The liquid or solid residue that forms when smoke cools and settles on surfaces. Analyzing smoke condensate can help fire investigators determine fire origin and the types of materials burned.

The physical harm caused to structures, furniture, or belongings by smoke from a fire. This damage can include discoloration, odor, and corrosive effects on surfaces and electronics.

Also known as a backdraft, this occurs when a fire smolders in an enclosed space, depleting oxygen and accumulating flammable gases. When oxygen is introduced, these gases ignite explosively.

The intake of smoke and combustion byproducts into the respiratory system, which can lead to serious health issues or death. Smoke inhalation is a common cause of fire-related fatalities.

A specially trained firefighter who parachutes into remote areas to combat wildfires. Smoke jumpers are deployed for rapid response to fires in locations inaccessible by traditional ground vehicles.

The practice of controlling and dispersing smoke from fires to minimize its impact on air quality and visibility. Techniques include controlled burns, timing operations, and using natural wind patterns to direct smoke away from populated areas.

The shapes and trails left by smoke deposits on surfaces, which can help fire investigators understand fire movement and ventilation conditions within a structure.

The process by which smoke is generated during combustion. Smoke production varies based on fuel type, temperature, and fire conditions.

The discoloration of surfaces caused by smoke deposits. Smoke staining can be used to identify fire paths and areas of higher heat exposure during an investigation.

The controlled removal of smoke from a building or structure to improve visibility and reduce heat buildup during a fire. Smoke ventilation can be natural, mechanical, or performed by firefighters using equipment like fans and exhaust vents.

A type of combustion that occurs at a low temperature and without visible flames, producing smoke and heat. Smoldering fires can persist for long periods and reignite if exposed to oxygen or a heat source.

A fire that burns slowly with little flame and produces large amounts of smoke. Smoldering fires are common in dense fuels like peat or insulation and can be difficult to fully extinguish.

A dead or dying tree that is still standing, which can become a fire hazard due to its dry and combustible nature. Snags can fall during a fire, posing risks to firefighters and property.

A type of battery that uses solid electrolytes instead of liquid or gel-based ones. While solid-state batteries are generally safer and less prone to fire, improper handling or damage can still result in combustion.

The property of a substance that allows it to dissolve in a solvent, such as water or alcohol. Understanding solubility is important for selecting fire suppression agents and analyzing fire debris.

Black, carbon-based particulate matter produced during incomplete combustion. Soot can settle on surfaces, contributing to smoke damage and posing health risks if inhaled.

The flaking or breaking away of a material's surface due to intense heat exposure. Spalling is commonly observed in concrete or masonry during fires and can provide clues about the heat intensity and duration at a fire scene.

A small particle of burning material or an electrical discharge that can ignite flammable substances. Sparks are a common source of fire ignition in welding, grinding, and electrical work.

The ratio of the density of a substance to the density of water. Specific gravity can be used to understand the behavior of liquid fuels and their interaction with water during fire suppression.

The amount of heat energy required to raise the temperature of a unit mass of a substance by one degree Celsius. In fire science, understanding specific heat helps assess how materials absorb and transfer heat during a fire.

The focused location within the general origin area where the fire first ignited. Identifying the specific origin area is crucial for pinpointing ignition sources and determining the cause of a fire.

The alteration or destruction of evidence that can compromise an investigation. In fire investigations, preserving evidence is critical to avoid spoliation and ensure accurate analysis and legal proceedings.

The self-ignition of materials due to chemical reactions or heat buildup without an external flame or spark. This can occur with materials like oily rags, compost piles, or certain chemicals under the right conditions.

The process by which a material generates heat internally, often due to oxidation or microbial activity. If spontaneous heating reaches the material’s ignition point, it can lead to spontaneous combustion.

The process by which a material ignites on its own without an external ignition source due to internal heat generation. This phenomenon is common in certain organic materials or improperly stored chemicals.

A weather prediction specific to a small area or incident, often used for managing wildfires or planned burns. Spot weather forecasts help fire managers anticipate changes in wind, temperature, and humidity that could affect fire behavior.

A person responsible for observing and providing guidance during aerial firefighting operations. Spotters ensure that drops are accurate and safe for firefighting crews on the ground.

The process where burning embers or brands are carried by wind or convection and start new fires away from the main fire. Spotting can significantly increase the spread of wildfires.

A location where firefighting resources, such as equipment and personnel, are assembled and prepared for deployment. Staging areas are strategically chosen to facilitate efficient response and coordination.

The current level of electrical charge in a battery, expressed as a percentage of its total capacity. Monitoring SOC is essential for battery safety to prevent overcharging and potential fires.