A new method is described for the quantitative determination of formaldehyde in air, particularly formaldehyde emission from particleboard. A sample volume of 1 liter air is sufficient for analysis in the range 0.1 to 1 mg/m³. The air sample is collected in a gas buretteand the formaldehyde is then extracted in a small amount of water. The formaldehyde concentration in the water extract is finally determined by the acetylacetone method combined with fluorescence spectroscopy. For nondestructive testing of large specimens, the desiccator may be replaced with a bell letting the board sample constitute a bottom in the bell. -- AATA