Indoor air quality
Indoor air quality investigations
When occupants report stuffiness, odors, headaches or poor comfort, we measure what is in the air, check how the ventilation system is actually performing, and explain what to change.
What we do
Measure the air, check the system, find the cause
- Occupant complaint investigationsInterviews and a short questionnaire to map where and when symptoms or odors occur.
- Direct-reading monitoringCarbon dioxide, carbon monoxide, temperature, relative humidity, PM2.5 and PM10, and total VOCs, logged through the occupied day.
- Ventilation reviewOutdoor air intakes, filters, supply and return, and CO₂ levels as an indicator of outdoor air delivered per person.
- Targeted samplingFormaldehyde, specific VOCs, mold or other contaminants when the findings point to a particular source.
- Move-in and post-renovation checksBaseline air quality before a space is occupied, or after construction, flooring or furniture installation.
- Odor and contaminant source tracingRe-entrainment from exhausts, garage and loading dock fumes, sewer gas, and construction dust migration.
Benchmarks
What results are compared against
- Carbon dioxide
- Not a toxic concern at indoor levels. About 700 ppm above outdoor (roughly 1,100 ppm indoors) is widely used as an indicator of adequate ventilation. OSHA PEL: 5,000 ppm.
- Carbon monoxide
- EPA outdoor standard 9 ppm over 8 hours. Indoors, readings above outdoor levels point to a combustion source.
- Relative humidity
- EPA recommends keeping indoor humidity between 30% and 50%, and below 60% to limit mold growth.
- Thermal comfort
- ASHRAE 55 defines comfort ranges by temperature, humidity, air speed, clothing and activity.
- Ventilation
- ASHRAE 62.1 sets minimum outdoor air rates by occupancy type and floor area.
Fine particulate (PM2.5) benchmarks
Process
How an air quality investigation runs
Intake
We review complaints, the floor plan and HVAC information, and agree on the areas to evaluate.
Walkthrough
Inspection of occupied spaces, mechanical rooms and air intakes, with occupant interviews.
Monitoring
Direct-reading measurements in complaint and comparison areas, plus outdoor readings.
Follow-up sampling
Only where monitoring or the walkthrough points to a specific contaminant.
Report
Findings against benchmarks, likely causes, and prioritized recommendations for the building team.
FAQ
Common questions
Is high CO₂ dangerous?
At typical indoor levels, no. Elevated CO₂ mostly tells you the space is not getting enough outdoor air for the number of people in it, which often goes along with stuffiness and complaints.
Do you always take lab samples?
No. Many investigations are resolved with direct-reading instruments and a ventilation review. Lab sampling is added only when results point to a specific contaminant.
Can you test before we move into a new office?
Yes. A baseline survey before occupancy documents conditions and catches problems from new finishes or ventilation set-up.
Next step
Complaints about the air in your building?
Tell us the address, the area affected and what occupants are noticing. We will propose an investigation.