Static and Automatic Air Monitoring

The reference methods usually require wet samplers. Sampling trains have been developed that allow the sampling of five or more gases simultaneously in separate bubblers. These static methods of sampling can be accomplished with a modest initial investment, but the manpower required to distribute and pick up the samples and to analyze them in the laboratory raises the total cost to a point where automated systems may be more economical for long-term studies. 

Post-Oil Energy Technology After the Age of Fossil Fuels 

Description of the high-volume column air sampler (a) illustrates the assembled sampler and its shelter (b) shows the components of a typical high-volume air sampler. 

As the need for accurate data that can be statistically reduced develops, automated sampling systems are used. The elements of an automated system include the airflow-handling system, sensors, data transmission storage, display apparatus, and data processing facility. The overall system is no more valuable than the weakest link of this chain. 

Periodic performance audits are required to validate the accuracy of the air-monitoring system. The Code of Federal Regulations (CFR) requires that performance audits be conducted at least once a year for criteria pollutant analyzers operated at state and local air monitoring stations (SLAMS). The EPA recommends that each analyzer be disconnected from the monitoring station manifold and be individually connected to the audit, from which it will receive the audit gas of known concentration. The audit gas concentrations are usually generated in a van, using a gas calibrator to dilute multiblend gases with zero air. 

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