Quantitative Aerosol Generator

Xact® 825 Quantitative Aerosol Generator (QAG)

QAG + control+PC


The Quantitative Aerosol Generator (QAG) creates an aerosol of known concentration by nebulizing a solution. The resulting droplets are carried out of generation area to a drying chamber where they are dried to salt particles. Depending on the application for the salt particles the size can be varied to a number mean between 0.1 and 2 µm in diameter. The aerosol exiting the drying chamber contains a known concentration of analytes that is calculated from the QAG’s input parameters. This reference aerosol produced by the QAG is process traceable to NIST (National Institute for Science and Technology) standards and can be used to challenge and evaluate the accuracy, precision, and linearity of measurement methods such as the Xact™ series monitors during certification and RATA.


  • Quantitative aerosol traceable to NIST Standards
  • Simultaneous for one or more elements
  • Wide range: ng/dscm to mg/dscm
  • Automatic mass loss reporting
  • Single operator with minimal input requirements


Possible applications include evaluation, verification, audits, and certification of metals and PM measurement systems. It is applicable to both metal and non-metal species, as well as generic PM aerosols

Approved by US EPA for Multi-metal CEMS Audits and Certifications

Stability has been demonstrated through repeated use in the laboratory and in the field for over five years. The QAG can be operated by one user with minimal parameter inputs and control. The QAG is able to generate aerosols of most inorganic analytes including most hazardous elements in stack and fugitive emissions, as well as those present in the ambient environment. This instrument is the first quantitative aerosol generator to be approved by EPA for evaluating, validating and certifying continuous multi-metals CEMS used for compliance demonstration. The QAG greatly simplifies the certification and auditing of multi-metal CEMS and eliminates the need to compare multi-metal CEMS results to less precise and less accurate traditional multi-metal reference methods, such as EPA Reference Method 29.

Technical Literature

Traceability Profile