
Moisture
Can cause allergy problems and structural damage by encouraging the growth of molds, mildew, bacteria, dust mites, dry rot, and insects.
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Common household chemicals
- Cleaning supplies
- Paints and solvents
- Formaldehyde from furniture, carpet, and building materials
- Pesticides
- Volatile organic compounds
- Odors
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Particles
- Dust and dust mites
- Pet dander
- Pollen
- Lead
- Asbestos
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Tobacco smoke
A health risk to xmokers and nonsmokers alike. Children are especially at risk.
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Combustion products
(From fuel-burining heating equipment, gas water heaters, fireplaces, woodstoves, gas ranges, candles)
- Carbon monoxide
- Carbon dioxide
- Nitrous oxides
- soot
- Unburned fuel
- Moisture
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Heat
Overheating in attic from sun exposure.
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