What type of sensors can be evaluated?

AQ-SPEC evaluates air quality sensors that are widely commercially available and measure the common criteria pollutants such as carbon monoxide (CO), ozone (O₃), nitrogen dioxide (NO₂), particulate matter (PM_2.5 and PM₁₀) and sulfur dioxide (SO₂). We can also evaluate the performance of sensors measuring methane (CH₄) and volatile organic compounds (VOC).

In order to be considered for evaluation, a sensor must meet the sensor selection criteria below.

Sensor selection criteria

• The sensors 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 (NO_x), particulate matter (PM_2.5 and PM₁₀), volatile organic compounds (VOCs), sulfur dioxide (SO₂), and methane (CH₄).

• The sensors shall be capable of measuring ambient concentration levels.
• The sensors shall be widely commercially available.
• The sensors must be new and submitted as a triplicate for testing.
• The sensors shall provide real- or near-real time measurements.
• The sensors data recording time resolution must be shorter than 5 minutes and the data must be retrievable as a file.
• The data collected by the sensors must be accessible by AQ-SPEC throughout the evaluation time period.
• The market cost of the sensors shall be considered “low-cost” such that the cost for each parameter that is measured is less than $2,000.

What is the charge for a sensor evaluation?

Currently, there is no charge for AQ-SPEC sensor evaluations. The AQ-SPEC program is funded by the South Coast AQMD.

How many sensors should I send for the AQ-SPEC evaluation?

AQ-SPEC evaluates sensors in triplicate, so three new identical sensors must be received by AQ-SPEC to perform an evaluation.

Where should I send my three air quality sensors to be evaluated?

Please send your sensors to the AQ-SPEC team at the address indicated below:
South Coast AQMD
Attn: AQ-SPEC / Randy Lam
21865 Copley Drive
Diamond Bar, CA 91765
USA

How long will the evaluation take?

First, sensors are evaluated in the field at one of SCAQMD’s fixed air monitoring stations for 8 weeks. Depending on the field testing results, sensors may subsequently be evaluated under controlled environmental conditions (e.g. variable temperature and relative humidity) in the AQ-SPEC laboratory chamber. 

When will the sensor evaluation report be published on the website for viewing?

The field testing evaluation report is typically published within a month of the conclusion of the 8-week field co-location test against US EPA approved method instruments (e.g., regulatory-grade, research-grade)

My sensor is not ruggedized for ambient air quality monitoring. Can it still be tested under AQ-SPEC?

Yes. Sensors that are not ruggedized are placed in our custom-built instrument shelter. This shelter protects the sensors from the weather while being open enough to sample ambient air quality conditions.

I have manufactured a raw sensor with no power or data communication/storage options. Can it still be tested under AQ-SPEC?

No. The raw sensor must be integrated with power and data communication/storage options at the factory. AQ-SPEC does not integrate raw sensors with power and data options for an AQ-SPEC evaluation.

What type of power is provided for field testing? 

The instrument shelter is wired with 120 volt A/C power. For DC sensors, please provide the appropriate AC/DC converter. 

What type of connectivity is provided at the Ambient Air Quality Station? 

Wi-Fi and Ethernet connectivity are available at the SCAQMD air monitoring station. 

Where are the field sites located? 

Field deployments typically take place at either the SCAQMD Rubidoux air monitoring station or at the Interstate 710 freeway site in Long Beach (a near-roadway monitoring station). 

Where can the sensor evaluation reports be found? 

Reports for field and laboratory testing can be found by going to the AQ-SPEC Evaluations page.   

For additional questions about our sensor testing protocol and/or other aspects of the AQ-SPEC program, please contact:           

South Coast AQMD / AQ-SPEC
21865 Copley Drive
Diamond Bar, CA 91765-4178
AQ-SPEC hotline for sensor-related questions only: +1 (909) 396-2713
E-mail: info.aq-spec@aqmd.gov