Sick building syndrome

Sick building syndrome investigation

Sick building syndrome describes a cluster of non-specific complaints — headaches, fatigue, eye and throat irritation — that correlate with occupancy of a particular building. Monitoring identifies the environmental factors that warrant further investigation; it does not diagnose medical conditions.

CO₂612 ppmPM2.58 µg/m³VOC0.21 mg/m³RH46 %

Common contributors

Environmental factors typically reviewed

No single cause explains SBS. The investigation pattern is to measure each likely contributor against established references and identify the combination that aligns with the complaint pattern.

Ventilation

CO₂

Persistently elevated CO₂ indicates undersupplied outdoor air.

Chemistry

TVOC / HCHO

Material and cleaning emissions linked to irritation.

Particles

PM2.5

Combustion, traffic ingress and indoor activity.

Comfort

T / RH

Temperature and humidity outside comfort ranges.

Symptom-to-zone mapping

Occupant reports are mapped against zone, shift, weather and HVAC mode before sensors are deployed.

Calibrated continuous monitoring

Multi-parameter sensors across affected and control zones for a representative period.

Ventilation review

AHU strategy, fresh-air rates and exhaust performance compared against design intent.

Findings and next steps

Clear written report, benchmark comparison and prioritised actions that support — but do not replace — medical or HR advice.

When to investigate

Triggers for an SBS-style investigation

Clusters of complaints concentrated in one part of a building, symptoms that ease at weekends or away from the site, post-refurbishment reports, and persistent complaints that have not been resolved by reactive checks. Investigations help separate environmental factors from unrelated medical issues.

Combine with indoor air investigations, poor indoor air quality review and continuous air quality monitoring.

Benchmarks

Reference frameworks used

ReferenceParameterApplication
BS EN 16798-1 Cat IICO₂ < ~800 ppm above outdoorOffice ventilation target
WHO IAQ GuidelinesPM2.5, NO₂, HCHOHealth benchmarking
CIBSE Guide A21–23 °C / 40–60 % RHComfort envelope
WELL v2 AirTVOC < 500 µg/m³Occupant-facing target
HSE INDG244Workplace temperatureStatutory comfort guidance

Investigate building-related complaints

Calibrated monitoring and ventilation review to identify the environmental factors at play.

Request a quote