Volatile organic compounds, or VOCs, are a broad group of carbon-containing chemicals that can evaporate into indoor air. Formaldehyde is one specific VOC. Treating every VOC as one pollutant hides important differences in source, concentration, health significance and how it can be reduced.
Where can they come from?
Possible indoor sources include pressed-wood products, some furniture and cabinetry, paints, adhesives, flooring, cleaning products, fragrances, tobacco smoke, combustion and hobby materials. Emissions often change with product age, temperature, humidity and ventilation.
A new smell does not identify the chemical or concentration. Some VOCs have little odour, while a strong odour does not automatically establish a dangerous dose.
What should you do first?
- 01Find likely sources.
Look at recent renovation, new furniture, stored chemicals, smoking, combustion and product use.
- 02Remove or reduce the source.
Follow product instructions, close containers and move avoidable emitting materials out of occupied space.
- 03Ventilate when outdoor air is suitable.
Increase fresh-air exchange during and after painting, cleaning or installation work where practical.
- 04Measure only with a clear question.
A broad consumer VOC number cannot reliably identify formaldehyde or every individual chemical.
Formaldehyde deserves specific attention
The World Health Organization gives a short-term indoor-air guideline of 0.1 mg/m³ averaged over 30 minutes for formaldehyde. Interpreting a result requires a suitable method, sampling location and timing. A low-cost general VOC sensor is not automatically a formaldehyde test.
Can an air purifier help?
Ordinary particle filters target particles, not gases. Gas reduction requires suitable sorbent media and enough media, contact time and capacity for the substance and conditions involved. Performance declines as media is used, and a smell disappearing does not prove that every gas has been removed.
Air cleaning can support source control and ventilation, but it should not be used to justify leaving a strong avoidable source in the room.
When to seek help
Leave the area and seek appropriate help for severe eye or airway irritation, breathing difficulty, dizziness or suspected combustion exposure. Persistent concerns after renovation or in a workplace may justify assessment by a qualified indoor-air professional using pollutant-specific methods.
Official guidance