Standards Development

Scope

This part of ISO 16200 gives general guidance for the sampling and analysis of volatile organic compounds (VOCs) in workplace air by solvent desorption/gas chromatography using diffusive sampling. This part of ISO 16200 is applicable to a wide range of VOCs, including hydrocarbons, halogenated hydrocarbons, esters, glycol ethers, ketones and alcohols. A number of devices and sorbents are recommended for the sampling of these VOCs, each sorbent having a different range of applicability.

Note 1 to entry: Activated coconut shell charcoal is frequently used. Very polar compounds may require derivatization, very low boiling compounds may only be partially retained by the sorbents, polar or high boiling compounds may not be quantitatively extracted by the chosen solvent. In these cases, their concentration may be quantitatively determined, provided that reverse diffusion and analytical recovery studies are available.

This part of ISO 16200 is valid for the measurement of airborne vapours of VOCs in a concentration range of approximately 0,1 mg/m3 to 1 000 mg/m3 individual organic for an exposure time of 8 h.

The upper limit of the useful range is set by the sorptive capacity of the sorbent used and, subject to dilution of the analysed solution, by the linear dynamic range of the gas chromatograph, column and detector or by the sample splitting capability of the analytical instrumentation used. The lower limit of the useful range depends on the noise level of the detector and on blank levels of analyte and/or interfering artefacts on the sampling devices or in the desorption solvent. Artefacts are typically sub-nanogram for activated charcoal, but higher levels of aromatic hydrocarbons have been noted in some batches. By applying this part of ISO 16200, the lower limits of quantification achieved are typically in the range of 0,01 µg to 1 µg of a given VOC per sample. Determination of the blank value for target organic compounds is recommended for each lot of samplers.