Testing for fire smoke and soot damage is an essential step after any fire event in a property. While some damage is easy to see, tiny particles and toxic chemicals can linger unseen, settling deep within HVAC systems, wall cavities, and porous materials. These hidden contaminants can pose lasting health and safety risks long after the visible signs of fire have been addressed.
Health Risks of Smoke and Soot Exposure
Smoke and soot are made up of complex mixtures of gases and fine particles (PM2.5), which can be inhaled deeply into the lungs and enter the body through the respiratory system.
- Respiratory Issues: Exposure may cause ongoing coughing, wheezing, and irritation of the eyes, nose, and throat. It can also trigger or worsen existing conditions such as asthma and bronchitis.
- Cardiovascular Stress: The fine particles found in soot can enter the bloodstream and increase the risk of heart attacks, strokes, and coronary heart disease.
- Toxic & Carcinogenic Exposure: The specific risks depend on what materials burned—soot from materials like plastics and treated woods can contain heavy metals and hazardous chemicals such as benzene, formaldehyde, and dioxins. Soot itself is classified as a carcinogen by the National Cancer Institute.
- Vulnerable Populations: Groups such as children, the elderly, and individuals with chronic heart or lung conditions are particularly susceptible to severe health effects from exposure.
Lithium-Ion Battery Fires vs Traditional Fires
As of 2026, fire safety experts differentiate lithium-ion battery fires from standard house fires by their extreme volatility, unique chemical hazards, and difficulty in extinguishing. While normal fires typically involve materials like wood, paper, or plastic (Class A), lithium-ion battery fires are chemical events known as thermal runaway.
Key Differences in Fire Behaviour
- Thermal Runaway: Battery fires start from an internal chain reaction. Once a cell overheats, it generates its own heat and oxygen, spreading uncontrollably to adjacent cells.
- Rapid Intensity: Lithium fires can reach temperatures of up to 900°C within minutes, much faster than most standard building fires.
- Explosive Vents: Before visible flames, batteries may vent with "jet-like" flames or explosive vapours, possibly bursting the casing and ejecting metal fragments.
- Re-ignition Risk: Batteries can appear extinguished but may still contain "stranded" energy, leading to re-ignition hours or even days after the initial fire.
Different Health & Chemical Risks
The smoke from lithium-ion battery fires is considerably more dangerous than smoke from burning wood or typical household materials:
- Toxic Cocktail: Lithium fires emit highly toxic gases, particularly hydrogen fluoride (HF), which can cause severe respiratory distress, poisoning, and lasting lung damage.
- Hydrofluoric Acid: Battery chemicals can react with moisture in the air or lungs to form hydrofluoric acid, a substance that causes deep tissue burns and irritates eyes and skin.
- Heavy Metal Residue: Smoke from battery fires may carry heavy metals such as cobalt and lithium. Specialised testing by industrial hygienists is needed to confirm a property is safe for re-entry.
Suppression and Remediation Challenges
The smoke from lithium-ion battery fires is considerably more dangerous than smoke from burning wood or typical household materials:
- Water Reactivity: Standard water-based extinguishing methods may worsen lithium-ion battery fires, as burning lithium reacts with water to release flammable hydrogen gas, potentially intensifying the fire.
- Extinguisher Limitations: Common extinguishers like ABC dry chemical or CO2 types are often ineffective. Updated safety guidelines recommend specialised agents such as F-500 or aqueous vermiculite dispersion (AVD).
- Post-Fire Cleaning: The unique chemical markers and heavy metals in lithium soot mean normal cleaning is often inadequate. Professional remediation with post-remediation verification by a hygienist is typically necessary to confirm removal of toxic residues.
Why Professional Testing is Required
Professional testing offers scientific evidence to ensure a property has been properly cleaned and is safe for occupancy—not just what the eye can see.
- Identify Hidden Contamination: Smoke particles can spread far and settle in places like attics, floorboards, and electronics. Testing uncovers these hidden hazards before they cause long-term health or property damage.
- Inform Remediation Strategies: Accurate testing guides restoration teams in selecting the right cleaning approaches, preventing further spread of soot and ensuring the removal of all toxic residues.
- Validate Cleaning Success: After cleaning, "clearance" testing ensures the property meets safety standards and is ready for re-occupancy.
- Support Insurance Claims: Documented pre- and post-testing provides the proof needed for insurance claims and helps resolve disputes.
- Regulatory Compliance: Testing ensures properties comply with 2026 workplace air quality and environmental safety standards, such as those established by the EPA and Safe Work Australia.
Common Testing Methods in 2026
- Air Quality Monitoring: This method measures concentrations of soot, carbon monoxide, and volatile organic compounds (VOCs) in the air.
- Surface Sampling: Technicians collect samples using tape-lifts or chemical sponges to distinguish between fire soot and normal dust through laboratory analysis.
- Microscopic Analysis: Sophisticated tools like Polarised Light Microscopy (PLM) or Scanning Electron Microscopy (SEM) are used to identify the specific composition of fire-related particles.
ANSI/IICRC S700 Standard for Professional Fire and Smoke Damage Restoration
The ANSI/IICRC S700 Standard for Professional Fire and Smoke Damage Restoration, published in 2025, is the industry’s official "standard of care" for fire recovery. It ensures recovery work is carried out with scientific accuracy and attention to safety.
Summary of the IICRC S700 Standard
The S700 provides a detailed framework for assessing, mitigating, and restoring buildings and contents after fire and smoke incidents. It aims to make restoration transparent and consistent for all parties. Key elements include:
- Rigorous Assessment: Professionals must thoroughly define the extent and intensity of fire residues (soot) and odours, inspecting even hidden areas such as wall cavities and interstitial spaces.
- Restoration Work Plan (RWP): A comprehensive, written plan must document each project phase, from initial test cleaning to final verification.
- HVAC Systems & Air Quality: The standard includes specific requirements for inspecting and cleaning heating, ventilation, and air-conditioning systems to ensure no toxic residues are circulated.
- Health and Safety: Worker and occupant safety are prioritised, with mandates for using appropriate Personal Protective Equipment (PPE) such as single-use coveralls and respirators.
- Post-Restoration Evaluation: Final evaluation is required to confirm that all fire-related residues and odours have been removed effectively before restoration is considered complete.
Why the S700 Matters for Your Property
Before the introduction of S700, restoration methods varied widely by provider. Now, adherence to this standard guarantees:
- Objective Safety: Properties are returned to a safe, liveable state based on scientific evidence rather than guesswork.
- Insurance Alignment: Following the S700 ensures that contractors provide the documentation and measurable outcomes insurers require for fair settlement of claims.
- Specialised Expertise: The standard clarifies that fire restoration is a specialised field requiring dedicated training and advanced equipment, beyond what general cleaning covers.
For more information or to access professional guidelines, visit the IICRC Standards.
IOHC Occupational Hygiene Services
The IOHC occupational hygiene team offers expert support in evaluating properties impacted by fire. Our team is highly experienced in monitoring a range of hazards, including airborne dusts and metals, gases, volatile organic compounds (VOCs), soot residues, and surface contamination. With our base in Brisbane, we provide comprehensive coverage across Queensland and northern New South Wales. If you require further information or tailored advice, please reach out to our approachable team.
Do you have Questions?
Call our office, our qualified hygienists are here to help.
Disclaimer – The information in this blog is for informational purposes only and is not intended as medical/financial/legal advice. Always consult with a professional before making any decisions based on this information. No guarantees or warranties are expressed by IOHC about the accuracy of the information contained in the blogs.
