Diffusive samplers for ambient air quality monitoring

Air pollution remains a matter of concern for governments, regulators and the general public. Diffusive, or passive, samplers provide a cost-effective, versatile and spatially dense method to sample air pollution that does not require the significant investment needed to operate traditional air quality monitoring instrumentation. This Technical Brief describes the theory and operation of diffusive samplers and how their sampling rates may be calibrated. It also discusses considerations for the deployment of diffusive samplers in outdoor environments and provides examples of their practical use in sampling different air pollutants.