What Should Be Tested After a Fire in Washington?

After a house fire, commercial building fire, or wildfire, one of the most common questions is:

What should actually be tested?

There is no single laboratory test that is appropriate for every fire.

The environmental testing strategy depends upon what burned, how smoke traveled through the property, whether building materials were damaged, whether ash entered or settled around the property, and what questions the investigation needs to answer.

5 Microns Inc. provides independent post-fire environmental testing throughout Washington State for residential properties, commercial buildings, insurance-related investigations, and consultant-directed projects.

Depending upon the circumstances, post-fire testing may evaluate soot, char, ash, combustion particles, PAHs, selected metals, VOCs, and other environmental contaminants.

When regulated building materials such as asbestos or lead-based paint are involved, separate regulatory requirements may also apply.

Start With the Fire, Not a Generic Testing Package

Every fire is different.

A small kitchen fire involving food and cooking materials presents a different environmental situation than a garage fire involving vehicles, plastics, fuels, and stored chemicals.

Likewise, wildfire smoke entering a building several miles from a fire is different from a wildland-urban interface fire where houses, vehicles, and manufactured materials burned near the property.

Before selecting laboratory analyses, important questions include:

• Where did the fire occur?
• What materials burned?
• How extensive was the fire?
• Which areas experienced direct fire damage?
• Where did smoke travel?
• Did the HVAC system operate during the event?
• Was ash deposited inside or outside?
• Were neighboring structures involved?
• Were vehicles, electronics, plastics, or other manufactured materials burned?
• Is testing being performed before or after remediation?
• Is the investigation related to an insurance claim?

The answers help determine what should be sampled and which laboratory analyses may be appropriate.

1. Soot Testing After a Fire

Soot is one of the most commonly investigated residues following a fire.

Soot generally consists of fine carbonaceous particles generated during incomplete combustion.

Because these particles can travel with smoke, soot may be deposited well beyond the area where flames were present.

Potential sampling locations include:

• Walls
• Ceilings
• Floors
• Window sills
• Cabinets
• Countertops
• Furniture
• HVAC components
• Attics
• Garages
• Personal belongings

Laboratory examination of representative surface samples can provide information about particles present in selected areas.

This can be particularly useful when the extent of smoke migration is uncertain.

2. Char Testing

Char is another potential indicator of combustion.

Char particles originate from partially burned or carbonized materials and may be transported with smoke or deposited near the fire.

Microscopic examination of collected particulate material can help identify combustion-related particles present on selected surfaces.

Soot and char investigations are often useful when visual observations alone cannot determine whether dark particulate matter is associated with a fire.

Not every dark particle in a building is fire residue, which is one reason laboratory analysis and site context are important.

3. Ash Testing

Ash may be an important component of an investigation following:

• Structure fires
• Wildfires
• Wildland-urban interface fires
• Nearby building fires
• Large commercial fires

Ash can settle on roofs, decks, patios, vehicles, landscaping, soil, exterior equipment, and interior surfaces.

The appropriate analysis depends upon the source of the ash and materials that burned.

Ash generated primarily by vegetation can differ substantially from ash generated when structures, vehicles, electronics, plastics, and other manufactured materials burn.

4. Combustion Byproduct Testing

A modern structure contains many different materials.

When those materials burn, combustion can generate a complex mixture of particles and chemical residues.

Potential materials involved in a structure fire may include:

• Plastics
• Electronics
• Furniture
• Flooring
• Synthetic fabrics
• Roofing
• Insulation
• Adhesives
• Coatings
• Appliances
• Treated wood
• Stored products
• Vehicle components

Depending upon the circumstances, environmental testing may extend beyond soot and char to evaluate other combustion byproducts.

The appropriate analytical scope should be based upon the actual fire rather than an automatic panel applied to every property.

5. PAH Testing After a Fire

Polycyclic aromatic hydrocarbons, or PAHs, are a group of compounds associated with incomplete combustion.

PAHs may be considered during certain fire and smoke investigations, particularly when the materials involved or project objectives warrant chemical analysis.

Depending upon the investigation, samples may be collected from selected surfaces or other appropriate media and submitted to a qualified laboratory.

PAH testing is not necessarily required following every fire.

The decision should be based upon the nature of the fire, suspected exposure, and purpose of the investigation.

6. Metals Testing After a Fire

Selected metals may become an environmental concern when certain building materials, electronics, vehicles, painted components, equipment, or other manufactured products burn.

Depending upon the project, metals may be evaluated in:

• Surface wipe samples
• Ash
• Settled material
• Soil
• Other appropriate environmental media

The metals selected for analysis should reflect the materials involved and the purpose of the investigation.

For wildfire-affected properties, this can become particularly relevant when the fire has burned structures and manufactured materials rather than vegetation alone.

7. VOC Testing After a Fire

Volatile organic compounds (VOCs) may also be considered in some post-fire environmental investigations.

Combustion, heat-damaged materials, chemicals, coatings, furnishings, plastics, and other products can potentially contribute VOCs to indoor air.

VOC testing may be considered when:

• Chemical or unusual odors persist
• Manufactured materials were heavily involved
• A commercial or industrial fire occurred
• Indoor-air conditions are part of the investigation
• Other evidence indicates that air sampling may be warranted

VOC testing is not a substitute for soot or surface-residue testing.

These methods answer different environmental questions and may be used together when appropriate.

8. Surface Testing

Much of a post-fire investigation involves determining what has deposited on surfaces.

Surface sampling may involve:

• Tape lifts
• Wipe samples
• Other project-specific collection methods

Sampling locations should be selected strategically.

For example, an investigation may include samples from:

• Heavily affected areas
• Moderately affected areas
• Rooms away from the fire
• Suspected smoke-migration pathways
• HVAC-associated areas
• Appropriate comparison locations

A thoughtful sampling strategy generally provides more useful information than simply collecting a large number of samples without a defined objective.

9. Testing Furniture and Personal Belongings

Smoke and combustion particles can affect contents without directly burning them.

Potentially affected property may include:

• Furniture
• Electronics
• Clothing
• Textiles
• Artwork
• Household belongings
• Kitchen contents
• Office equipment
• Stored items

Representative testing may be useful when there are questions about whether selected contents experienced fire-related contamination.

This frequently becomes relevant during insurance claims involving decisions about cleaning, restoration, or additional evaluation of personal property.

10. Soil Testing After a Fire or Wildfire

Post-fire contamination is not always limited to the building.

Ash and debris can deposit on surrounding soil.

Soil testing may be considered following:

• Wildfires
• Structural fires
• Garage fires
• Fires involving vehicles
• Fires involving manufactured materials
• Significant exterior ash deposition

The appropriate laboratory analyses depend upon what burned and the suspected contaminants.

Sampling design can also consider location, depth, visible deposition, and suitable comparison areas.

11. Asbestos Considerations After a Fire

Fire-damaged buildings may contain asbestos-containing materials, particularly older structures.

Potential materials can include certain:

• Insulation
• Floor coverings
• Ceiling materials
• Wall systems
• Roofing products
• Mechanical-system materials
• Other building components

Fire damage can disturb building materials and complicate subsequent demolition, repair, or remediation.

Asbestos is regulated separately from general soot, char, and combustion-residue testing.

When asbestos inspection is required under Washington regulations, the applicable inspection and certification requirements must be followed.

General post-fire environmental sampling should not be treated as a substitute for a required asbestos inspection.

12. Lead-Based Paint Considerations

Lead may also become relevant following a fire, particularly when older painted building components are damaged.

Washington requirements governing regulated lead-based paint inspections and risk assessments may apply to certain residential and child-occupied properties.

Lead-based paint evaluation should therefore be distinguished from general fire-residue testing.

If regulated lead inspection or risk-assessment services are required, those services should be performed under the applicable certification requirements.

Should You Test the Entire Property?

Not necessarily.

The appropriate extent of testing depends upon the fire and how contamination may have migrated.

A fire confined to one area may still affect additional portions of the building through smoke movement, but that does not automatically mean every surface in every room requires laboratory analysis.

A better approach is to develop a representative sampling strategy based upon:

Fire location → smoke pathways → visible conditions → suspected contaminants → project questions.

That strategy can then be adjusted based upon field observations.

Should the HVAC System Be Evaluated?

HVAC systems can be important pathways for smoke movement.

If an HVAC system operated during or after a fire, smoke and particles may have traveled through ductwork or associated building areas.

An environmental investigation may therefore consider:

• Supply and return areas
• Registers
• Accessible HVAC components
• Areas served by the system
• Patterns of smoke migration

The appropriate evaluation depends upon the building and circumstances of the fire.

Should Testing Be Done Before Cleanup?

When feasible, pre-remediation testing can be particularly valuable because it documents environmental conditions before cleaning changes the property.

Pre-remediation testing may help establish:

• Which areas were affected
• What residues were identified
• Where contamination was found
• Which areas may warrant remediation
• Baseline conditions for later verification

This can be especially useful during insurance-related investigations.

Should Testing Be Done After Cleanup?

Post-remediation verification can provide an independent evaluation after fire and smoke cleaning has been completed.

Depending upon the project, verification may involve:

• Visual observations
• Representative surface sampling
• Laboratory analysis
• Comparison with previously affected locations
• Photographic documentation

Using an independent environmental testing company for verification separates the evaluation from the contractor that performed the remediation.

What Should Be Tested After Wildfire Smoke Exposure?

A property does not have to burn to experience wildfire-related environmental effects.

Depending upon the proximity and severity of the event, testing may consider:

• Soot and char
• Ash
• Surface residues
• Interior particulate deposition
• Exterior deposits
• Selected metals
• PAHs
• Soil
• Other project-specific contaminants

The testing strategy should distinguish between distant vegetation-fire smoke and properties near wildland-urban interface fires where structures and manufactured materials also burned.

What Should Be Tested for an Insurance Claim?

There is no special laboratory test simply because an insurance claim exists.

Instead, testing should address the environmental questions relevant to the loss.

These may include:

• How far did smoke contamination travel?
• Are combustion particles present outside the burned area?
• Were contents affected?
• Did ash contaminate exterior areas?
• Are additional contaminants associated with what burned?
• What were conditions before remediation?
• What conditions remain after remediation?

Independent testing can provide environmental evidence that assists the parties involved in evaluating those questions.

5 Microns does not determine insurance coverage or claim value.

Field Sampling for Environmental and Insurance Consultants

5 Microns provides Washington field support for environmental consultants, insurance-loss consultants, catastrophe-response organizations, and other firms requiring local personnel for post-fire investigations.

We can perform fieldwork according to a consultant-provided sampling protocol.

Services may include:

• Tape-lift sampling
• Surface wipe sampling
• Soot and char sampling
• Ash sampling
• Soil sampling
• Contents sampling
• Detailed site photographs
• Sample-location photographs
• Field observations
• Sample mapping
• Chain-of-custody preparation
• Laboratory coordination
• Sample packaging and shipment

This service is available for individual properties as well as qualifying multi-property assignments.

Post-Fire Environmental Testing Throughout Washington

5 Microns provides post-fire testing throughout Washington State, including:

Spokane • Spokane Valley • Wenatchee • Yakima • Tri-Cities • Richland • Kennewick • Pasco • Moses Lake • Ellensburg • Seattle • Bellevue • Tacoma • Everett and surrounding Washington communities.

Statewide mobilization can be coordinated for qualifying residential, commercial, insurance, wildfire, and consultant-directed projects.

How 5 Microns Determines What to Test

The objective is not to sell every available laboratory analysis.

The objective is to identify the environmental questions created by the fire and select sampling methods capable of addressing those questions.

A typical process may include:

1. Review the fire and property history.
2. Identify materials known or suspected to have burned.
3. Inspect accessible areas.
4. Evaluate smoke and ash migration.
5. Determine the contaminants of concern.
6. Develop representative sampling locations.
7. Collect and document samples.
8. Submit samples to appropriate environmental laboratories.
9. Evaluate laboratory findings in conjunction with field observations.
10. Determine whether additional investigation or verification is warranted.

Schedule Post-Fire Environmental Testing in Washington

If your home, commercial property, or building has experienced a fire, wildfire, or significant smoke exposure, 5 Microns can help determine which environmental testing methods are appropriate for the circumstances.

We also provide Washington field sampling for environmental consultants and insurance-related organizations requiring local personnel for fire-loss investigations.

Contact 5 Microns Inc. to discuss what should be tested following a fire anywhere in Washington State.