Of the 50+ volatile organic compounds commonly measured indoors, the top five by mass are formaldehyde, terpenes, BTEX (benzene/toluene/ethylbenzene/xylene), acetaldehyde, and siloxanes. Most indoor VOC exposure isn’t a ventilation problem; it’s a product-swap problem. Ventilation handles the leftover.
Five sources to know about
1. Engineered wood (formaldehyde). Particleboard, MDF, and plywood furniture made before California’s 2008 CARB Phase 2 rule can off-gas for years. Cabinets, bookshelves, the underside of cheap bed frames. Newer U.S.-sold products meet stricter limits, but imports and vintage pieces are wildcards. You can’t easily eliminate this short of replacing the furniture.
2. Cleaning products and air fresheners (terpenes). Anything with a “fresh lemon” or “pine forest” scent emits terpenes. Terpenes react with indoor ozone to form formaldehyde and ultrafine particles. Plug-in air fresheners are the worst. This one you can eliminate: switch to fragrance-free cleaners and unplug the air fresheners.
3. Attached garages (BTEX). Homes with attached garages routinely show benzene, toluene, and xylene even when nobody’s using the car. Tank evaporation, spilled gasoline, stored solvents migrate through the shared wall. Hard to eliminate if you have a garage and a car. Move solvents and paint outside, weather-strip the connecting door.
4. Cooking (acetaldehyde, acrolein, PM2.5). Pan-frying and baking spike indoor concentrations 10–100x for hours. You can’t stop cooking, and your range hood may not be helping as much as you think.
A 2014 LBNL survey of newer California homes found about 13% had recirculating (ductless) range hoods that don’t exhaust outside, and another 4% had no hood at all. The number is meaningfully higher in older housing stock and apartments. If yours doesn’t vent outside, the cooking VOCs you generate stay in the room.
5. Personal care products (siloxanes). Hairspray, deodorant, lotions, dry-cleaned clothes release cyclic siloxanes. The reason your bathroom and bedroom often have higher VOC readings than your kitchen. You won’t stop using deodorant; ventilation is the answer.
Health effects, briefly
Short-term: headaches, eye and throat irritation, dizziness, fatigue. Resolves when exposure ends. Long-term, the picture is compound-specific. Formaldehyde and benzene are IARC Group 1 carcinogens. Acetaldehyde is Group 2B. Terpenes plus indoor ozone form ultrafine particles linked to respiratory irritation. The CDC has individual fact sheets.
What to do about each one
Eliminate when you can. Stop the air fresheners. Move solvents out of the garage.
Substitute when you can’t eliminate. Low-VOC paints with real third-party certifications (GreenGuard Gold, SCS Indoor Advantage Gold). Vent the range hood outside if your kitchen is renovated.
Ventilate for everything you can’t fix at the source. Cooking. Garage spillover. Personal care. Off-gassing furniture you can’t replace. Continuous mechanical ventilation handles all of these without you thinking about it.
Filter as a partial backup. Activated carbon captures certain VOCs. HEPA does not remove VOCs at all.
Where Vyana fits
Dual Vyana is the configuration most homes need. The intake unit, near your HVAC return register, brings in filtered outdoor air, which the HVAC fan distributes through every supply register. The exhaust unit at the far end pushes stale, VOC-laden air out, pulling air across rooms in the process. Whole-house cross-ventilation. Cooking VOCs get carried out instead of settling. Garage-air migration gets diluted before it accumulates. Personal-care siloxanes leave with the morning bathroom traffic.
Solo Vyana is fine for small single-zone spaces, but only Dual delivers the cross-ventilation that actually clears VOCs out of every room.
Frequently asked questions
Do VOCs stay in a home for weeks after painting?
Yes. Surface drying is solvent evaporation, but the polymerized paint releases residual VOCs for weeks. Low-VOC paints reduce the spike but not the tail. Run ventilation continuously during and after painting.
Can houseplants remove VOCs?
Barely. Waring (Drexel, 2019) showed you’d need 10 to 1,000 plants per square meter in a real home to match cracking a window. Plants are great for mood. Not IAQ.
Is a HEPA filter enough for VOCs?
No. HEPA filters particles. VOCs are gas-phase molecules orders of magnitude smaller. Activated carbon helps. Ventilation is the only thing that broadly works.