Low-cost sensors make it possible to watch indoor conditions continuously, but a dashboard is only useful when facility teams know what each measurement can and cannot reveal. The strongest programs look for patterns tied to occupancy, weather and equipment operation.
1. Carbon dioxide: a ventilation and occupancy clue
People exhale carbon dioxide, so indoor CO2 commonly rises when occupancy increases faster than outdoor air is delivered. At concentrations typically encountered in ordinary occupied buildings, the reading is most useful as an indicator of ventilation performance and occupancy patterns. It should not be treated as a complete air quality score.
Track when CO2 rises, which rooms differ and whether levels recover after occupancy. A recurring classroom or conference-room pattern can point to scheduling, damper, balancing or ventilation issues.
2. PM2.5: fine airborne particles
PM2.5 includes fine particles from outdoor pollution, smoke, cooking, combustion and some indoor activities. Compare indoor and outdoor trends when possible. A sudden indoor spike may reflect an activity; a building-wide rise that follows outdoor smoke may reveal filtration or envelope limitations.
3. Relative humidity
Humidity influences comfort, condensation, dust mites and mold risk. Averages can hide the problem. Track overnight peaks, wet-weather response, seasonal differences and localized conditions near exterior walls, basements, crawlspaces or HVAC zones.
4. Temperature
Temperature changes relative humidity and occupant perception. A cold surface can support condensation even when the room-average humidity seems acceptable. Temperature complaints can also reveal airflow, solar gain, insulation or control issues that overlap with air quality concerns.
5. VOC trends
Many consumer sensors report a total or relative VOC index rather than identifying individual chemicals. Use the trend to locate patterns around cleaning, renovation, occupancy or ventilation changes. Do not treat a generic VOC index as a chemical-specific exposure assessment.
Metrics that require separate professional attention
Carbon monoxide and radon are important, but they should be addressed with purpose-built devices and qualified professionals. Tune My Space does not provide certified radon, lead or asbestos inspection. A general IAQ sensor is not a replacement for compliant testing.
Turn measurements into building questions
- Does the pattern follow occupancy or weather?
- Does it occur in one zone or across the building?
- What changed in HVAC schedule, outdoor-air position or filtration?
- Are sensors placed away from direct supply air, windows and unusual local sources?
- Do measurements agree with maintenance observations and occupant reports?