In April 2008, the State of California adopted an airborne toxic control measure (ATCM) to reduce formaldehyde emissions from composite wood products, proposed by the California Air Resources Board (CARB), part of the California Environmental Protection Agency. Phase 1 started in January 2009, and at the end of the implementation, in July 2012, formaldehyde emission limits will range between 0.05 and 0.13 ppm, depending on the type of products, based on the ASTM E 1333 Large Chamber Method.
These new limits are in the order of the limits of detection of the current analytical methods presently used, and rendered the chromotropic acid reaction, on which the ASTM E 1333 is based, with a limit of detection of 0.01 ppm less precise.
An alternative method to determine formaldehyde concentration in air has been developed to be used as part of the ASTM E1333 Large Chamber Method. 60 L of air are sampled through an impinger containing an acetylacetone-ammonia solution. The solution is then heated, and analyzed by fluorimetry using a Turner Quantech filter fluorometer equipped with a NB430 excitation filter and a SC500 emission filter. The test method is inexpensive, easy to use, compatible with the Large Chamber, Perforator and Desiccator Methods, and is very sensitive. The minimum detection limit (MDL) and the limit of quantification (LOQ) of this analytical method are 0.0004 and 0.0013 ppm, respectively.