Application and Validation of a Pocket Diffusive (POD) Sampler for Determination of VOCs in Air Using TD-GCMS

Air Methods, Monitoring, and Technology
Poster Presentation

Prepared by

Contact Information: nwatson@markes.com; 866-483-5684


ABSTRACT

Diffusive, or passive sampling has been widely adopted as a sampling technique for determination of volatile organic compounds (VOCs) in air. It offers a convenient, low-cost and unobtrusive solution for a range of applications including industrial hygiene and indoor air monitoring and is well suited to large-scale environmental monitoring campaigns. Whilst axial and planar (badge) samplers remain the most widely adopted passive sampling approaches, radial samplers with their increased sampling rate can offer advantages for short-term monitoring or longer-term sampling at trace levels.
A novel pocket diffusive sampler (POD) has been developed and validated in both laboratory and field tests. POD Sampler has also been used for the monitoring of C4-C9 hydrocarbons in shale gas in the US, with an extended analyte range reported including PAHs and light PCBs. The design of the sampler introduces several performance improvements over existing designs, with optimised geometries and dimensions to reduce impact of wind velocity, increase sampling efficiency and provide better mechanical performance. Furthermore, trace-level analysis is aided by the sampler’s optimised analyte/adsorbent ratio, which minimises artefact levels.
This poster will present results from performance validation of the final sampler design, including sampling rates, reproducibility and sample stability. Further work will focus on extension of performance data indicating the sampler’s suitability over an extended volatility range compared with existing radial devices.