Fine particles (PM2.5)
PM2.5 is the headline air-quality metric: particles under 2.5 microns, fine enough to reach deep into the lungs. It is one of the most health-relevant pollutants there is, linked to heart and lung disease worldwide. Indoors it comes from cooking, smoke and outdoor pollution finding its way in.
The pollutant with the biggest health toll.
PM2.5 is among the most studied and most harmful air pollutants — and one of the clearest wins from good filtration and ventilation.
Heart & lungs
Long-term PM2.5 exposure is linked to heart disease, stroke and reduced lung function; short peaks worsen asthma and allergies.
Global health priority
PM2.5 is responsible for millions of premature deaths a year — the reason WHO tightened its guideline in 2021.
Visible wins
Filtration and source control cut PM2.5 quickly; monitoring shows the improvement in real time.
Certification
WHO, WELL, LEED and RESET Air all set PM2.5 limits. Continuous data is your evidence of clean air.
Benchmarked to the WHO guideline.
The WHO 2021 24-hour guideline is 15 µg/m³, with an annual target of just 5 µg/m³. Healthy interiors stay within these; higher bands follow common air-quality indices.
Cooking, smoke and the air outside.
Indoor PM2.5 is a mix of what you generate inside and what infiltrates from outdoors — and it tracks both closely.
Cooking
Frying, grilling and high-heat cooking are the dominant indoor PM2.5 source in most occupied buildings.
Smoke & combustion
Tobacco, candles, fireplaces and nearby wood-burning push PM2.5 up sharply.
Outdoor air
Traffic, industry and wildfires raise outdoor PM2.5 that enters through ventilation and gaps.
Resuspension
Foot traffic and cleaning lift settled dust back into the air, adding to the fine-particle load.