You can’t always see poor indoor air quality, but you may notice its effects. Persistent headaches, allergy flare-ups, musty odors, or unexplained respiratory issues can all be signs that airborne contaminants are affecting your indoor environment. Because most people spend approximately 90% of their time indoors, understanding the quality of the air inside homes, offices, schools, and commercial buildings is more important than ever.

From mold and allergens to VOCs and airborne particles, indoor contaminants can impact the spaces where people live and work. Professional testing helps uncover what may be affecting indoor air quality.

In this guide, we’ll cover:

• What indoor air quality testing measures
• The most common indoor air pollutants
• How professional air quality testing works
• When to schedule an indoor air quality test
• Why testing plays an important role in maintaining healthier indoor environments

What Is Indoor Air Quality Testing?

Indoor air quality testing collects and analyzes air samples inside a building. It shows which pollutants are present and at what level.

A visual inspection can’t catch everything. Carbon monoxide, radon, and many VOCs have no smell or color. Testing detects what a walkthrough would miss.

Air quality testing services are commonly used in:

• Residential homes
• Commercial offices
• Schools and universities
• Healthcare facilities
• Industrial buildings
• Government properties
• Construction and renovation projects

Indoor air quality concerns can result from moisture issues, renovations, or everyday pollutants. Professional testing helps identify potential contaminants and assess indoor environments. 

The air quality testing hub provides an overview of the air testing services available for different property types and applications.

What Pollutants Does Indoor Air Quality Testing Measure?

A complete air quality test evaluates several pollutant categories. Identifying each one protects occupant health.

Biological Pollutants

Biological contaminants circulate through indoor air. Higher concentrations can trigger allergies, asthma, and respiratory irritation.

Air contaminant testing can identify:

• Mold spores
• Bacteria
• Pollen
• Dust mites
• Pet dander
• Fungal organisms

These pollutants build up in damp, poorly ventilated spaces like crawl spaces, attics, and HVAC systems. Testing shows whether levels are safe.

VOC Testing

VOC testing is one of the most requested parts of an air quality inspection. VOCs are chemicals that evaporate from everyday products and building materials.

Common sources include:

• Paints and varnishes
• Cleaning products
• Adhesives and solvents
• Air fresheners
• Furniture and flooring
• Fuel vapors

Many VOCs are undetectable without lab analysis. Short-term exposure can cause headaches and eye irritation. Long-term exposure raises the risk of more serious health effects.

Professional environmental air testing accurately measures VOC concentrations and helps determine whether indoor levels pose a potential health risk.

Combustion Pollutants

Combustion pollutants come from burning fuels like natural gas, propane, or wood. Poorly vented appliances let them build up indoors.

Common combustion pollutants include:

• Carbon monoxide
• Nitrogen dioxide
• Sulfur dioxide
• Fine particulate matter
• Smoke particles

Sources include fireplaces, gas stoves, furnaces, and generators. Many combustion pollutants are invisible, making air contaminant testing important for detecting indoor air contaminants.

Carbon Monoxide

Carbon monoxide has no color, smell, or taste. Faulty heating equipment or poor ventilation can let it build up without warning.

Symptoms include headaches, dizziness, fatigue, and confusion. High concentrations can become life-threatening fast. Testing identifies CO sources before they become dangerous.

Radon

Radon testing is a key part of any indoor air quality test. Radon is a radioactive gas that rises naturally from soil and rock.

It enters buildings through foundation cracks and utility openings. It has no color, smell, or taste, so testing is the only way to detect it.

The EPA lists radon as the second leading cause of lung cancer in the U.S. Testing helps catch elevated levels early, before long-term exposure becomes a risk.

Allergens

Indoor allergens affect comfort and health, especially for people with asthma. Indoor environmental testing identifies what’s circulating through the air.

Common allergens include:

• Pet dander
• Dust mites
• Pollen
• Insect debris
• Mold spores

Results show whether better ventilation or filtration is needed.

PFAS and Emerging Contaminants

Testing programs increasingly cover emerging contaminants alongside standard pollutants. Labs may assess airborne chemicals tied to manufacturing or firefighting foams.

PFAS testing is more common in water and soil analysis. Some industrial sites also require airborne PFAS evaluation.

Mold Air Testing

Mold often hides behind drywall, under flooring, or inside HVAC systems. A small plumbing leak can create the moisture mold needs to grow.

Mold air testing measures airborne mold spores. It can also identify:

• Hidden mold colonies
• Water damage indicators
• Moisture-related contamination
• Indoor fungal activity

Pair mold testing with water testing services for a fuller picture of contamination sources.

Particulate Matter Testing

Airborne particles are among the most common indoor pollutants. Particulate testing measures particles small enough to reach deep into the lungs.

Testing typically evaluates:

• PM2.5
• PM10
• Dust particles
• Smoke
• Construction debris

High particulate exposure has been linked to asthma and cardiovascular issues. Monitoring matters most in schools, healthcare facilities, and buildings under renovation.

How Is Indoor Air Quality Testing Performed?

Air quality testing combines field sampling with lab analysis.

1. Initial Site Assessment Specialists review the property’s history, ventilation, and any reported concerns. They check for signs of moisture or poor airflow.
2. Air Sample Collection Technicians collect indoor air samples from selected locations. Outdoor samples may also be collected for comparison.
3. Laboratory Analysis Samples go through validated lab methods to identify VOCs, mold spores, allergens, and particulate matter.
4. Results Interpretation Lab professionals explain what was detected and recommend next steps. This gives property owners real data to act on.

Indoor air quality testing is one component of full laboratory testing services that support environmental and industrial testing requirements.

Why Indoor Air Quality Testing Is Important

Many indoor pollutants go unnoticed. Left unaddressed, they can affect health and productivity over time.

Air quality testing helps:

• Detect hidden mold before it spreads
• Identify harmful gases and chemicals
• Evaluate ventilation effectiveness
• Improve indoor comfort
• Support workplace health and safety
• Establish baseline conditions
• Guide remediation decisions
• Meet environmental regulations

Torrent Laboratory also provides Environmental Testing Services covering air, water, soil, and workplace contaminants.

When Should You Schedule an Indoor Air Quality Test?

Schedule a test whenever there’s a concern about indoor air safety.

Common situations include:

• Recurring headaches or allergies
• Visible or suspected mold growth
• Recent flooding or water damage
• Persistent musty or chemical odors
• Recently completed renovations
• Unexplained employee health symptoms
• Property purchase, lease, or renovation
• Ongoing monitoring requirements

Routine testing also fits well into a preventative maintenance schedule.

Indoor Air Quality Testing in the Bay Area and California

Indoor conditions vary by climate, building age, and materials. Local testing gives a more accurate assessment.

Torrent Laboratory serves residential, commercial, industrial, and government clients across San Jose, the Bay Area, Silicon Valley, and Northern California. Our team understands the region’s building types and environmental conditions, from coastal fog to inland heat.

Reach out to us to discuss your indoor air quality concerns!

Frequently Asked Questions

What contaminants are measured during an indoor air quality test?

Professional indoor air quality testing can detect mold spores, bacteria, allergens, volatile organic compounds (VOCs), combustion pollutants, radon, particulate matter, and other airborne contaminants depending on the scope of the assessment.

Can air quality testing detect mold?

Mold air testing measures airborne mold spores and helps identify hidden mold growth that may not be visible during a standard building inspection.

How often should indoor air quality testing be performed?

The recommended frequency depends on the building’s age, occupancy, environmental conditions, and any previous contamination issues. Commercial facilities often include periodic testing as part of ongoing environmental monitoring programs.

What are the signs of poor indoor air quality?

Common signs include persistent odors, excessive dust, recurring allergies, headaches, respiratory irritation, visible mold growth, increased humidity, and unexplained fatigue among occupants.

Is indoor air quality testing worth it?

Professional testing provides objective laboratory data that helps identify hidden pollutants, supports healthier indoor environments, and guides appropriate remediation strategies.

How much does indoor air quality testing cost?

Costs vary depending on the size of the property, the number of contaminants being analyzed, and the specific testing methods required. Contacting a qualified environmental laboratory is the best way to obtain a customized estimate.