Solvent from diffusive samplers

Figure 2 Types of diffusive samplers. From the left a colorimetric length-of-stain sampler a tube-type sampler for thermal desorption a badge-type sampler with multiple channels and no windscreen, containing a removable sorbent pad for solvent desorption a badge-type sampler with multiple channels and an internal windscreen, containing granular sorbent for in situ solvent desorption a badge-type sampler with an external vtrind-screen, behind which is an open diffusion path, and containing a sorbent pad for in situ solvent desorption.

Passive samplers are used for specific applications such as for indoor air environments or as passive dosimeters. In this approach, the air containing the organic diffuses to and adsorbs on a solid sorbent without active pumping. The organics are subsequently thermally desorbed or extracted from the sorbent using a solvent (e.g., see Shields and Weschler, 1987). 

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