Sources of indoor particulate matter
| Outdoor particulate matter (industry, traffic, etc.) |
| Cooking (gas versus induction, cooker hoods) |
| Fireplaces (wood and coal) |
| Combustion heating |
| Smoking or e-cigarette/vaping devices |
| Dust |
| Biological matter (mould spores, house dust mites, pet dander, pest droppings) |
| Scented candles/incense |
| Aerosols (from cleaning, air fresheners, etc.) |
Information from [8].