Materials
Formaldehyde
A simple organic gas used in many adhesives and resins for wood-based panels and furniture. It can off-gas into indoor air after manufacture and installation.
In more detail
Formaldehyde (CAS 50-00-0) is a volatile compound widely used as a binder and adhesive component in composite wood and related products. In occupied buildings, the main indoor sources are typically wood-based materials and the furniture and fittings made from them, along with some coatings, foams, and combustion byproducts.
The European Union classifies formaldehyde as a Category 1B carcinogen under the CLP Regulation ("may cause cancer"). That classification describes hazard under the regulatory scheme; indoor risk depends on concentration, exposure duration, and source strength. Agency guidance distinguishes irritation at higher indoor levels from the conditions associated with cancer findings in high-exposure settings.
What the term does not mean: a formaldehyde reading is not a stand-in for total VOC load, and "formaldehyde-free" marketing is not the same as "no emissions of any kind." Naturally occurring formaldehyde in some materials is also treated differently from formaldehyde added through resins in production.
Why it matters
Composite wood shows up throughout a house — cabinet boxes, shelving, flooring underlays, interior panels. Those assemblies can release formaldehyde into the rooms people actually use. Specifying lower-emitting panels and adhesives is one of the few material decisions that directly changes what ends up in indoor air after finish work is done.
The common misunderstanding
That any wood product is automatically clean because wood is "natural," or that a low TVOC reading proves formaldehyde is under control. Formaldehyde is a specific compound; aggregate VOC scores and material origin claims do not substitute for compound-specific emission limits or tests.
Related terms
On Compound
Where this term does real work — and where the decisions get made.
Sources
Last reviewed August 2026 by Compound Editorial. Definitions are educational and not project-specific engineering or medical advice.