The Passive Air Quality Sampler (PAQS) provides a cost-effective method for collecting air quality data. This system does not require power, making it an excellent tool for sampling in regions that are remote or local, large or small. An additional advantage to the simple but effective design of the sampling device is the ease in which the PAQS is deployed and operated.

Passive sampling devices operate on the principles of adsorption and permeation, physically binding to the specific compounds that are being targeted. Air pollutants that are being sampled will diffuse or permeate through a semi-permeable membrane and then collect on a filter that has been chemically treated to adsorb those targeted compounds. After being exposed, the sample is analyzed in the laboratory for the amount of the targeted compound collected. An average concentration is then calculated based on the duration of exposure (accounting for the effects of relative humidity, temperature and wind speed).

Sampling filter media are currently available for sulphur dioxide (SO2), hydrogen sulphide (H2S), nitrogen dioxide (NO2), and ozone (O3). Development is currently underway so that additional parameters may be accommodated. The sampling system, which allows for up to four (4) samplers, consists of a rain shelter, mounting hardware and room inside for storing on-site blanks. One shelter can support duplicate sampling of two parameters.

Application
Passive monitoring is available for use as an alternative to the continuous monitoring analyzers in numerous applications. Other sampling uses include indoor, workplace or personal monitoring. Compliance or regulatory monitoring (static monitoring) is the most common form of use. Results can be utilized in long term trending of collected data and can be operated either independently or part of a larger network of samplers. The PAQS can continue to be used for repeat sampling as the filters are submitted to our laboratory for analysis.

Validation
A field-testing and validation study performed at numerous locations in Alberta and British Columbia gave results that indicated a very close comparison to the much more costly continuous ambient air monitoring analyzers. Other field-testing and validation studies have been performed yielding very successful results comparing the AGAT PAQS to other alternative passive systems.