Wildfires are a part of life in our region. Every season, much of California and Nevada is blanketed with smoke. Particles from that smoke find a way into all structures. As such, there is a natural unavoidable background level of wildfire-related particles in our cars, homes, schools, offices and hospitals. However, an abnormal abundance of wildfire-particles can create undesirable effects (damages) such as odors, discoloration and even corrosion due to the pH range of certain types of ash.

Smoke is a complex mixture of particles from combustion, the nature of which is dependent in part on fuel source, temperature and fire efficiency. Wildfires will produce microscopically recognizable particles that relate back to the types of fuels consumed.

Common microscopic constituents in dust after a wildfire include:

• Burnt clay/minerals from surrounding soil.
• Chemical fire-retardant dropped from aircraft.
• Charred, blackened fragments from incomplete combustion of vegetation such as grasses, leaves & bark.
• Ash, or white fragments of completely burned vegetation.
• Soot, or ultra fine black particles of carbon released during the inefficient (oxygen poor) combustion of various fuel sources.
• Any fuel can produce soot depending on combustion efficiency. Some soot types are oily and/or very odorous. Because of this, analysis of fire-related particles can often differentiate between sources; for example, wildfire, camping fire, structure fire, BBQ, cigarette, diesel truck exhaust, etc.

Within the scope of our typical fire evaluation, AirBasics can answer the following common questions:

• Are fire-related particles present?
• What areas of the building are affected and more importantly, which are not?
• What is the source of the fire-related particles, wildfire or something else?
• How substantially affected are the various areas of the home?
• What methods of cleaning & restoration will be most effective?

Testing for Fire-Related Particles

Samples of settled dust are collected and evaluated for the presence of fire-related particles. Samples are collected from surfaces by tape lift method using Scotch-brand frosted tape.

The samples are then submitted to a qualified materials science lab for microscopic analysis. In the lab, each sample is processed and examined by an expert analyst utilizing Polarized Light Microscopy and/or Reflected Light Microscopy.

Samples are examined for the presence and relative abundance of various types fire-related particles. Based on size, shape, color, and refractive properties, the various particles are also assessed as to their general source.