Performance of the Radiello® diffusive sampler for formaldehyde measurement: the influence of exposure conditions and ozone interference

Abstract

The radial diffusive standard sampler Radiello® filled with Florisil impregnated with 2,4-dinitrophenylhydrazine (DNPH) was evaluated with the goal of survey monitoring the formaldehyde concentration in indoor air for a 4.5 day sampling time. A Radiello® sampler provides measurements with a relative standard deviation of repeatability comprised between 1.5 and 4.0%, a high sampling rate assessed to 98.7 ± 2.8 mL min⁻¹ under standard conditions (temperature: 19.9 ± 0.5 °C and relative humidity: 52.9 ± 3.2%) and a detection limit of 0.5 μg m⁻³ for a 4.5 day sampling time. The influence of three environmental factors (temperature (T°), relative humidity (RH) and ozone concentration (O₃)) on the sampling rate was also evaluated in an exposure chamber following a fractional design of the experiment at two factor levels (low and high). Temperature is found to be the factor leading to the most significant variation of the sampling rate with an effect of +1.8% per °C. From the fractional design of the experiment, a model was set up for expressing the sample rate of Radiello® as a function of significant factors and the uncertainty on the sampling rate was assessed to 11.9% under the domain of tested conditions.