Volatile Organic Compounds: Analytical techniques: canister and sorbent tube

The measurement of volatile organic compounds (VOC) in air has been a topic of scientific investigation for many years. There are a number of methods to monitor VOC in the air. Since the number of VOC found in trace levels in the atmosphere is ever growing due to the improving analytical techniques, it becomes more critical to select the best sampling and analytical method. This work provides a basic, step-by-step and practical approach to understand various sampling techniques for VOC. Generally, methods for VOC sampling include collection of the whole air or pre-concentration of samples on adsorbents. Two methods, namely sorbent tube and canister method, are compared to find out how different and/or complementary they are. Characteristics of various adsorbents used for VOC sampling are described. Effects of different levels of humidity on sample recovery from canisters, one of the most critical and much needed topics of research, is also described together with the long term stability of VOC in canisters. Ozone precursor VOC and several criteria pollutants monitored at a traffic intersection in Prague are also discussed.