Formaldehyde measurements in libraries: Comparison between infrared diode laser spectroscopy and a DNPH-derivatization method

Formaldehyde concentrations have been measured in the university libraries in Strasbourg (east of France). Infrared diode laser spectroscopy and a conventional DNPH-derivatization method followed by liquid chromatography coupled to UV detection have been used simultaneously for comparison purposes.The formaldehyde concentrations obtained by both the techniques were always in excellent agreement, showing that the infrared diode laser spectroscopy can be used for formaldehyde monitoring in indoor atmosphere, with a time resolution of few minutes.Formaldehyde concentrations were generally found to be in the range 8–33 μg m−3, except for two libraries where concentrations of 82 and 105 μg m−3 have been measured. Using the results obtained by both techniques, the resulting mean formaldehyde level in the investigated libraries was then 33.5±31.2 μg m−3, where the quoted error correspond to the standard deviation.Acetaldehyde and hexanal levels have also been quantified by duplicated measurements in the same libraries by the DNHP-derivatization method. They ranged from 0.0 to 11.3 μg m−3 for acetaldehyde and from 1.0 to 16.7 μg m−3 for hexanal and their mean values were found to be 2.1±3.2 μg m−3 (acetaldehyde) and 4.0±4.4 μg m−3 (hexanal), where the quoted errors correspond to the standard deviation.