Identify and Quantify Smoke Hazards for Safe Reoccupation

Urban wildfires pose significant challenges not only during the blaze but also in their aftermath. For Industrial Hygiene Investigators, Insurance Loss Adjusters, and Consultants conducting indoor monitoring, assessing and quantifying post-fire smoke hazards is crucial to determine the safety and occupancy of affected structures. TSI offers tools to detect the hidden dangers of wildfire smoke inside homes and businesses, particularly after fires in the Wildland-Urban Interface (WUI). Our instruments help you assess aerosol contamination so that spaces are safe to reoccupy.

Understanding the Wildland-Urban Interface (WUI)

The WUI is where homes and human development meet wildland vegetation — forests, grasslands, or brush. Fires in these areas are especially hazardous:

They burn both natural and synthetic materials (homes, vehicles, EV batteries, plastics)
They generate complex combustion products — far beyond what’s seen in typical biomass (forest) only fires
Structures that survive can still be greatly affected / contaminated

These combustion products can include particulate matter, volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs), heavy metals, and other toxic contaminants. These contaminants can infiltrate structures, adhering to surfaces and penetrating porous materials, leading to prolonged off-gassing and potential health risks for occupants.

HVAC: The Hidden Contamination Highway

Smoke doesn’t just affect what you can see. HVAC systems act as highways that spread particles and gases into every room of a structure. Even if the system was off during the fire, particles can settle inside and off-gas for months or years. Porous materials (drywall, carpets, upholstery) also absorb and hold onto toxic particles, including secondary organic aerosols (SOAs).

Assess Smoke-Impacted Structures in Real-Time

As part of an assessment, you can leverage real-time count-based particle size measurement and gas detection before cleaning begins. This approach:

Uses Condensation Particle Counters (CNC) and Optical Particle Counters (OPC) for real-time Ultrafine (UFP) / Fine / Coarse aerosol readings
Compares indoor particle counts to outdoor baseline levels
Helps identify the most heavily impacted rooms — often aligned with wind direction or HVAC influence
Offers insights into ultrafine particles (UFPs) and fine particle size, which carry the highest health risk and have negligible mass concentration making them undetectable by mass-based sampling and analysis methods

The Hard Data You Need

The TSI P-Trak Ultrafine Particle Counter and AeroTrak Handheld Particle Counter Model 9306 bundle provides a powerful solution for professionals assessing post-fire urban wildfire smoke hazards in homes and commercial buildings. The P-Trak Ultrafine Particle Counter detects and tracks airborne ultrafine particles, helping investigators identify contamination sources, while the AeroTrak 9306 Handheld Particle Counter delivers precise measurement of particle concentrations across multiple size ranges. Together, these instruments can help enable Industrial Hygiene Investigators, Insurance Loss Adjusters, and Consultants to accurately quantify airborne contaminants, assess indoor air quality, and may help to determine whether structures are safe for occupancy or require remediation.
P-Trak UFP Monitor AeroTrak 9306 OPC