Air samples taken on collection media for laboratory analysis remain a highly sensitive and cost-effective means of assessment. However, collection of samples can be difficult using nonautomated samplers, particularly over long terms or at remote locations. This paper describes a number of automated air samplers for sorbent-tube and filter use. The samplers are batterypowered, portable and weatherproof. They are suitable for:
- Very rapid sampling of dual sorbent tubes for survey use. The sampler is very small and lightweight for ease of field use.
- Sequential sampling of 24 tubes over a period up to 1 month. This technology is suitable for long-term ambient and superfund site monitoring. A meteorological station can be integrated.
- Simultaneous sampling of 4 separate media at different flows during multiple events over a one month maximum period. This technology is useful for hazard identification and location.
- One application of interest to the environmental community is the use of a variant of the 24 tube sequential samplers by the United Nations for chemical weapon ban verification.
Sampling on collection media such as sorbent tubes or filters remains a highly effective means of ambient air assessment. The concentrating effects of the collection medium results in high sensitivity, while later analysis at a laboratory allows for more detailed analysis than is possible with an automated field instrument. Sampling can be useful for the following purposes:
- Hazard Identification
- Hazard Location
- Ongoing Hazard Monitoring
- Spot Surveys
However, manual sampling over extended periods or at remote locations is difficult and expensive. Thus, there is a need for samplers that take very rapid survey samples, as well as automated samplers that can be placed in the field and which will function over extended periods while maintaining an accurate audit trail.