ICC FM cheat sheet

Fire tetrahedron: fuel, oxygen, heat, and the uninhibited chemical chain reaction; removing any one leg extinguishes combustion. Legacy triangle omits the chain reaction.

Four fire classes drive agent selection: A (ordinary combustibles, water), B (flammable liquids, smothering/foam), C (energized electrical, nonconductive agent), D (combustible metals, dry powder), plus K for cooking oils in commercial kitchens.

Flammable/combustible liquid thresholds (IFC 2021): Class IA flash point <73 F and boiling point <100 F; Class IB flash point <73 F and boiling point >=100 F; Class IC flash point >=73 F and <100 F; Class II >=100 F and <140 F; Class IIIA >=140 F and <200 F; Class IIIB >=200 F.

Flammable gas threshold: a gas is flammable when a mixture with air is ignitable at <=1 atm and 68 F (20 C) in any proportion, or has a flammable range with air at 68 F regardless of lower limit.

Ignition temperature is the minimum temperature at which a material ignites without an external pilot; it differs from flash point (vapor ignition with pilot) and fire point (sustained burning).

Education program effectiveness is measured against behavior and outcome metrics (alarm presence, escape-plan practice, incident rates), not attendance counts alone.

Smoke alarms: ionization responds faster to flaming fires; photoelectric responds faster to smoldering fires. Both technologies are recommended for maximum warning.

Exit sign and path marking education: occupants have seconds to minutes; teaching two-ways-out, door-closing, and staying low targets the survivable interval.

Public education materials must match reading level and language of the served population; NFPA and USFA provide free reproducible materials for local distribution.

Occupant load factor divides floor area by a use-specific factor (e.g., assembly unconcentrated 15 sq ft/person; business 100 sq ft/person; educational classrooms 20 sq ft/person) to size exits.

Egress capacity: level components 0.2 in per occupant, stairways 0.3 in per occupant; required egress width is the larger of capacity-based and minimum-width requirements.

Two exits are required where occupant load exceeds the threshold for the use group (commonly 49 for assembly/mercantile/educational) or where travel distance exceeds limits.

Common path and travel distance limits are use-group specific; dead-end corridors are generally limited to 20 ft in nonsprinklered and 50 ft in sprinklered buildings.

Fire-resistance-rated assemblies are tested to ASTM E119 or UL 263; opening protectives (fire doors, fire windows, dampers) carry their own rating and labeling requirements.

Sprinkler design is governed by NFPA 13 (and 13R/13D for residential); plan review verifies hazard classification, density/area curves, and water supply adequacy.

Fire flow demand is estimated from the needed fire flow method (ISO) or local code tables using construction class, occupancy, and exposure; verify hydrant spacing and residual pressure.

High-piled storage (over 12 ft) triggers NFPA 13 Chapter 20+ design criteria; rack configuration, commodity class, and flue spaces change required density.

Construction-phase fire safety plans address hot work permits, temporary heating, site security, and standpipe/sprinkler availability during phased occupancy.

Fire pattern analysis: V-patterns point to the origin at the apex; charring depth and alligatoring indicate duration and intensity, not necessarily direction.

Heat transfer modes are conduction (through solids), convection (through fluids/gases), and radiation (line-of-sight, inverse-square falloff).

Flashover occurs when upper-layer temperature reaches roughly 1,100-1,200 F and heat flux at floor level exceeds about 20 kW/m2; post-flashover patterns differ from pre-flashover.

Arc mapping locates points where energized conductors arced; the arc site is not automatically the fire origin, only a location of electrical activity.

Spoliation and evidence chain: origin determination precedes cause determination; cause classifications include accidental, incendiary, natural, and undetermined.

Ignitable liquid detection uses headspace sampling, solid-phase microextraction, and GC-MS; absence of residue does not prove absence of liquid.

Burn indicators: calcination of gypsum, spalling of concrete, and melting of metals give temperature ranges (e.g., copper melts near 1,981 F) useful for timeline reconstruction.

Competing hypotheses must be tested against all physical evidence; NFPA 921 methodology requires eliminating alternatives before assigning cause.

Home ignition zone is divided into zones: 0-5 ft noncombustible (Zone 0), 5-30 ft lean/clean/green (Zone 1), and 30-100 ft reduced fuel (Zone 2); ember ignition is the dominant home-loss mechanism.

Structure ignition pathways: radiant heat, direct flame contact, and firebrand/ember accumulation in gutters, vents, and decks.

Defensible space is measured from the structure; slope increases required distance because upslope fire spreads faster and radiates more intensely.

WUI risk ratings combine fuel hazard, slope, aspect, and structural ignitability; many jurisdictions use a parcel-level score to prioritize mitigation.

Firewise USA recognition requires a community wildfire protection plan, an annual renewal, and documented volunteer hours and mitigation actions.

Evacuation planning uses trigger points tied to fire behavior, and 'Ready, Set, Go!' phases: Ready (prepare), Set (monitor and be ready to leave), Go (evacuate immediately).

Home hardening elements: Class A roof, noncombustible 6-inch fascia and soffits, ember-resistant vents (1/8-inch mesh or listed), tempered dual-pane windows, and noncombustible decking.

Prescribed fire and mechanical fuel reduction are the primary landscape treatments; treatments must be maintained because fuel regrows within years.

Fire extinguisher PASS: Pull the pin, Aim at the base, Squeeze the handle, Sweep side to side; only trained occupants should attempt suppression on small, contained fires.

Home escape planning: two ways out of every room, a meeting place, and a practiced drill at least twice a year; close doors while escaping to limit fire spread.

Cooking is a leading cause of home fires and home fire injuries; unattended cooking and combustible items near the cooktop are primary factors.

Heating equipment is a leading cause of home fire deaths in winter months; keep three feet of clearance around space heaters and never use ovens for heating.

Electrical education targets overloaded circuits, extension cords as permanent wiring, and counterfeit or damaged cords; AFCI/GFCI devices address specific failure modes.

Juvenile firesetter intervention programs use screening tools and family education rather than punishment alone; early intervention reduces recidivism.

Carbon monoxide is produced by incomplete combustion; detectors should be placed near sleeping areas and on each level, not directly above fuel-burning appliances.

Means of egress components: exit access (travel to exit), exit (protected path), exit discharge (to public way); each has distinct requirements.

Exit access travel distance is measured along the path of travel, not straight-line distance, and is measured to the nearest exit.

Fire alarm system plan review per NFPA 72 covers device spacing, notification appliance audibility (15 dBA above ambient), and survivability for high-rise.

Standpipe and hose system classes: Class I (2.5-inch for fire department), Class II (1.5-inch for occupant use), Class III (both).

Smoke control systems in atria and high-rise buildings use either pressurization or exhaust; design must demonstrate tenability during egress.

Type of construction (I-V) determines allowable height and area; Type I is most fire resistive, Type V least; sprinkler increases allowable area.

Fire department access roads require minimum width (commonly 20 ft), turning radius, and aerial apparatus access near building faces.

Fire cause determination uses the scientific method: identify the problem, collect data, develop hypotheses, test hypotheses, select the final hypothesis.

Negative corpus (declaring a cause without evidence) is discredited; undetermined is a valid and often correct classification.

Electrical fire indicators include beading of copper, melted insulation, and arc tracking; these must be distinguished from fire-caused damage.

Appliance and equipment failure analysis considers manufacturing defects, misuse, and lack of maintenance; recall databases can identify patterns.

Smoldering versus flaming combustion produces different residue and char patterns; smoldering often occurs in upholstery and insulation.

Photography and documentation should capture overall, medium, and close-up views before disturbance; sketches supplement photos with measurements.

Fire death investigation integrates toxicology (CO, cyanide), pathology, and scene analysis; COHb and cyanide levels inform survivability analysis.

Ember cast can travel over a mile ahead of the flame front; most homes ignite from embers, not the main fire front.

Community Wildfire Protection Plan (CWPP) is a collaborative document identifying values at risk, fuel treatments, and evacuation routes.

Structural triage during WUI incidents categorizes homes as defensible, non-defensible, or prep-and-hold based on access, fuel, and construction.

Water supply planning for WUI includes hydrant adequacy, draft sites, and tenders; many WUI areas lack municipal water.

Post-fire assessment documents structure survival and the factors that contributed, informing future code and education efforts.

WUI codes (e.g., IWUIC) regulate roofing, exterior walls, decks, and vegetation; adoption varies by jurisdiction.

Public alerting uses WEA, opt-in notification systems, and door-to-door notification; redundancy is essential because power and cell service may fail.

Needs assessment identifies the target audience, the specific fire problem, and existing resources before program design.

Logic models link inputs, activities, outputs, and outcomes; they make program evaluation and funding justification explicit.

Partnerships with schools, faith organizations, and healthcare providers extend reach beyond fire department channels.

Evaluation designs include pre/post surveys, observation of behavior, and long-term incident data; self-report alone is weak evidence.

Cultural competence requires adapting materials to language, literacy, and trusted messengers within the community.

Programs targeting older adults address cooking, smoking, and heating hazards; mobility and sensory limitations affect response time.

Youth programs (e.g., Learn Not to Burn) integrate fire safety into school curricula with age-appropriate content.

Submittal review checks completeness first: plans, calculations, product data, and hydraulic calculations must be present before technical review begins.

Plan review comments should cite the specific code section, describe the deficiency, and state the required correction.

Deferred submittals (fire alarm, sprinkler, smoke control) must be tracked and reviewed before occupancy.

Field inspection verifies that construction matches approved plans; deviations require revised plans and re-review.

Certificate of occupancy is withheld until all fire protection systems pass acceptance testing and are documented.

Acceptance testing references: NFPA 13 (sprinkler), NFPA 72 (alarm), NFPA 14 (standpipe), NFPA 20 (fire pump).

Record retention: approved plans and inspection records should be retained for the life of the building or per jurisdiction policy.

Scene safety assessment precedes entry: structural stability, electrical hazards, and hazardous materials must be evaluated.

Evidence is documented in place, photographed, and collected with chain-of-custody forms; packaging must prevent cross-contamination.

Debris sampling for ignitable liquids uses clean metal cans or approved containers; comparison samples from unaffected areas are essential.

Reconstruction may use scale models, computer fire modeling, and full-scale testing to test hypotheses.

Witness interviews should be conducted separately and documented with time, location, and interviewer identity.

Insurance and legal considerations: reports may be discoverable; accuracy and objectivity are paramount.

Laboratory analysis results must be interpreted in context; detection of a compound does not establish its role in ignition.

Fuel treatment types: prescribed burning, mechanical thinning, grazing, and herbicide; each has cost, timing, and maintenance considerations.

Shaded fuel breaks reduce fire intensity and provide access for suppression while retaining canopy.

Structure protection involves pre-treatment (gel, foam), removal of combustibles, and closing windows and vents.

Evacuation timing depends on fire behavior, road capacity, and population; late evacuation is a leading cause of WUI fatalities.

Shelter-in-place is a last resort when evacuation is not possible; it requires a structure with adequate fire resistance and a safe room.

Post-fire flooding and debris flow are secondary hazards; burned watersheds require erosion control and monitoring.

Mutual aid agreements and pre-positioning of resources improve response in WUI incidents.

Fire code inspections verify maintenance of fire protection systems, housekeeping, and means of egress.

Occupancy-specific requirements: assembly (crowd management), mercantile (exit access), residential (smoke alarms).

Fire prevention education for businesses includes employee training, evacuation drills, and hot work permits.

Public assembly permits may require crowd managers at a ratio (commonly 1 per 250 occupants).

Open burning regulations vary by jurisdiction and require permits and setback distances.

Fireworks and pyrotechnics require permits, storage requirements, and operator certification.

Code adoption cycles: model codes update every three years; jurisdictions adopt with amendments.

Sprinkler system types: wet, dry, pre-action, deluge; selection depends on freeze risk and response requirements.

Hydraulic calculations demonstrate that the system can deliver the required density at the most remote area.

Fire pump sizing considers churn, rated flow, and overload; acceptance testing verifies performance.

Standpipe systems require pressure regulation and hose valve accessibility.

Fire alarm zoning and addressable systems improve response and troubleshooting.

Smoke detection spacing depends on ceiling height and configuration; beam detectors for large spaces.

Mass notification systems integrate with fire alarm for emergency communication.

Compartment fire stages: incipient, growth, fully developed, decay; each produces distinct patterns.

Ventilation-limited fires produce incomplete combustion and smoke staining; ventilation changes can cause backdraft or flashover.

Backdraft indicators: pressurized smoke, smoke-stained windows, and inward air movement when opened.

Fire plume and ceiling jet behavior influence detector activation and sprinkler response.

Thermal degradation of materials produces distinct residues used in analysis.

Computer fire models (e.g., FDS) can test hypotheses but require validation against physical evidence.

Fire death investigation integrates toxicology and scene analysis.

Wildfire hazard assessments use fuel models, slope, aspect, and weather to estimate fire behavior.

Home Ignition Zone assessment evaluates structural ignitability and surrounding fuels.

Community risk reduction integrates education, engineering, and enforcement.

GIS mapping identifies high-risk parcels and prioritizes mitigation.

Fire behavior models (e.g., BehavePlus) predict spread rate and intensity.

Weather monitoring and red flag warnings trigger preparedness actions.

Post-fire assessments inform future risk reduction.

Messaging should be actionable and specific, not generic.

Use multiple channels: schools, media, social media, and community events.

Evaluate reach and behavior change.

Adapt to audience literacy and language.

Partner with trusted community messengers.

Use data to target high-risk populations.

Document program activities for funding.

Hot work permits require fire watch and area clearance.

Temporary heating devices require clearance and ventilation.

Site security prevents arson.

Standpipes should be available during construction.

Phased occupancy requires separation and protection.

Fire lanes must remain accessible.

Construction debris must be managed.

Document overall, medium, and close-up photos.

Use sketches with measurements.

Maintain chain of custody.

Interview witnesses separately.

Test hypotheses against evidence.

Classify cause: accidental, incendiary, natural, undetermined.

Retain records per policy.

Use trigger points for evacuation decisions.

Provide clear, timely public information.

Coordinate with law enforcement and emergency management.

Plan for vulnerable populations.

Use redundant alerting methods.

Conduct public education before fire season.

Evaluate evacuation after incidents.

Define measurable objectives.

Use pre/post surveys and observation.

Track long-term incident data.

Compare to baseline.

Report results to stakeholders.

Adjust program based on findings.

Document for funding.

Coordinate with other agencies.

Track deferred submittals.

Verify acceptance testing.

Document inspections.

Issue certificates of occupancy.

Retain records.

Communicate with applicants.

Use the scientific method.

Collect data systematically.

Develop and test hypotheses.

Eliminate alternatives.

Document all findings.

Classify cause.

Report objectively.

Develop a CWPP.

Conduct community education.

Implement fuel treatments.

Harden homes.

Plan evacuation.

Coordinate response.

Evaluate and update plans.