VOC & IAQ Index IAQ
A fused air-quality index that combines VOCs, CO₂, particulates and climate into a single, contextual reading — the one number to watch at a glance.
Every gas. Every particle. One honest score.
A single number for the whole room. VOCs are the invisible chemistry of indoor life — cleaning products, furniture off-gassing, cooking, candles, and even the residue of breath. On their own they are noisy; alongside CO₂, particulates, temperature and humidity, they become meaningful. The fused IAQ index is what you glance at; the per-channel readings are what you drill into.
Built around Bosch BME690 · VOC + sensor fusion.
The Bosch BME690 measures VOCs via a metal-oxide element alongside temperature, humidity and pressure. Envora's sensor-fusion engine weights the BME690 output against NDIR CO₂, laser-scattered PM, and climate data to produce a stable, drift-compensated IAQ index. Baseline tracking means the score adapts to your environment, not to a generic lab.
- Technology
- Bosch BME690 · VOC + sensor fusion
- Range
- IAQ 0–500 · TVOC contextual
- Accuracy
- BME690 reference performance
- Resolution
- 1 IAQ point
- Response
- < 10 s (VOC) · stabilises over minutes
- Units
- index
The IAQ index is a fused, drift-compensated value — not a single VOC concentration. Give Envora 24 hours from first power-on to settle its baseline before trusting absolute values.
Excellent. Pristine air, no significant VOC sources active.
— Bosch BME688/690 IAQ index
Good. Day-to-day indoor target.
— Bosch BME688/690
Lightly polluted. Open windows, increase ventilation.
— Bosch BME688/690
Moderately polluted. Identify the source: cleaning, cooking, off-gassing furniture.
— Bosch BME688/690
Heavily polluted. Vacate and ventilate aggressively. Check for off-gassing or smoke.
— Bosch BME688/690
Severely polluted. Likely active source — solvents, smoke, or a malfunctioning appliance.
— Bosch BME688/690
Extremely polluted. Leave the space and ventilate. Investigate for combustion or chemical release.
— Bosch BME688/690
Practical steps, not panic.
- Use the IAQ score as your "glance metric" — drill into the sensor tiles only when it drifts.
- VOC spikes after cleaning, new furniture or printing are normal — watch how long they take to return to baseline.
- Give the device 24 hours from first power-on to settle its VOC baseline before trusting absolute values.
Where this channel does its best work.
Mould & damp risk
Mould does not appear from nowhere. It is the visible end of months of sustained humidity your house has been trying to tell you about.
Read the guideAllergies & dust sensitivity
Dust mites, pollen, pet dander and chemical irritants all have fingerprints. Envora reads them so you can manage the triggers, not just the symptoms.
Read the guideLong-term toxic gas exposure
A CO alarm chirps at 35 ppm. Your nervous system reacts at 1. Envora watches the band that does not set anything off — but accumulates anyway.
Read the guideCooking pollution
Frying on a gas hob can push PM2.5 past a London roadside reading in six minutes. Most domestic extractors were never designed for it.
Read the guideWinter dry air
Winter heating in the UK regularly drops indoor humidity below 25%. Sore throats, cracked furniture, increased infection risk — all avoidable once you can see the number.
Read the guideOutdoor air events
Wildfire smoke, urban traffic peaks, garden bonfires. The wrong ventilation strategy turns a bad outdoor hour into a bad indoor week.
Read the guideIAQ, plus 10 more channels.
Envora One ships VOC & IAQ Index alongside ten other channels, fused into one IAQ score and calibrated at our bench. £249 one-time. Free for personal households.
Free UK & EU shipping · 2-year warranty · 30-day returns · Reply within one UK business day.