Recently added/updated:


In an effort to inform the general public about the actual performance of commercially available “low-cost” air quality sensors, the SCAQMD has established the Air Quality Sensor Performance Evaluation Center (AQ-SPEC) program. The AQ-SPEC program aims at performing a thorough characterization of currently available “low-cost” sensors under ambient (field) and controlled (laboratory) conditions.

Main Goals & Objectives

  • Evaluate the performance of commercially available "low-cost" air quality sensors in both field and laboratory settings
  • Provide guidance and clarity for ever-evolving sensor technology and data interpretation
  • Catalyze the successful evolution, development, and use of sensor technology

Sensor Selection Criteria

  • The sensor shall have potential for near-term use.
  • The sensor shall provide real- or near-real time measurements.
  • The sensor shall measure one or more of the National Ambient Air Quality Standards (NAAQS) criteria pollutants, air toxics, pollutants of concern and non- air toxics. Examples of the targeted gases and particles are carbon monoxide (CO), ozone (O3), nitrogen oxides (NOx), particulate matter (PM), volatile organic compounds (VOCs), hydrogen sulfide (H2S) and methane (CH4).
  • The market cost of the sensor shall be less than $2,000.
  • Turnkey products will be tested first.

Why did SCAQMD create the AQ-SPEC Program?

“Low-cost” air quality sensors have become an attractive means for local environmental groups and individuals to independently evaluate air quality. Until the creation of the AQ-SPEC program, there had not been an objective way to evaluate the performance of those devices and sensor data had usually been accepted at face value with no opportunity to evaluate precision and overall quality. Poor quality data obtained from unreliable sensors may not only lead to confusion but also jeopardize the successful evolution of “low-cost” sensor technology. Therefore, there is a need to characterize the actual performance of air monitoring sensors as well as to educate the public about the advantages of such devices and their potential limitations.
For more information on the evaluation process, visit our AQ-SPEC evaluations page.