Air Quality Updates

Air Quality Updates

Air sampling measurement sites have been set up around the perimeter of the hangar and in surrounding communities to provide information on pollutants in the air. While the sampling units are in place, air quality results will be provided for the public reference. Any questions regarding these numbers should be directed to the call center at (714)-426-2444.

What is Being Measured in the Air?

A variety of pollutants are being measured continuously such as particulate matter (PM), Volatile Organic Compounds (VOCs – a common contaminant), carbon monoxide, and sulfur dioxide.  

Pollutants collected and analyzed in a laboratory include asbestos and the following metals:


















Incident air quality reports will include the results of the primary pollutants of concern including PM, asbestos, lead and arsenic and if other pollutants are exceeding a health-based threshold, they will be identified.  Please note, that the pollutants selected are specific to this localized incident and thus may have differences of “air quality” compared to general regional air quality reporting (weather channel, IOS/Android weather information).

What is Particulate Matter?

"Particulate matter," also known as particle pollution or PM, is a complex mixture of extremely small particles and liquid droplets that exists in the environment including pollen, dust, and soil. For information about air quality index (AQI) and regional air quality monitoring, visit the AirNow website at  

You can view the Archived Air Quality Updates here.

What is Asbestos?

Asbestos is a natural occurring mineral that can be found in nature. It is even found inside California’s State rock, Serpentine. It was commonly used in many different building materials and products over the years. If asbestos fibers are released into the air, they pose a health risk when inhaled.

What are Toxic Metals in Air?

Certain metals are hazardous air pollutants, also known as toxic air pollutants or air toxics. These air toxics are known or suspected to cause cancer or other serious health effects, such as reproductive effects or birth defects at sufficient concentrations and durations.



Asbestos Found in Debris

On November 7, three bulk samples of debris were taken at Veterans Sports Park and the results of laboratory testing detected asbestos. The three samples showed 25% asbestos, 27% asbestos, and 17% asbestos, respectively. The final report for these bulk samples can be found here

On November 8, six bulk samples of debris were taken at and around the perimeter of the hangar. Five of those samples showed 37%, 28%, 26%, 20%, and 16% asbestos. The final report can be found here: Bulk Samples Tustin Hangar.  These samples confirm that asbestos has been found in ash and debris from the fire, and these materials should be considered hazardous and avoided. A Certified Asbestos Consultant (CAC) should be retained by the responsible party (or parties) to identify and help address potential asbestos-containing materials as soon as possible. 

Air Pollution Discharge Notice was issued on 11/9 notifying the City of Tustin, the Orange County Board of Supervisors, and the Orange County Health Officer of the discharge of hazardous materials likely to impact public health or safety.    

Air Sampling 

Fixed monitors were placed at four locations (Veterans Sports Park, OC Sherriff’s Regional Training Center, Legacy Magnet Academy and Amalfi Apartments) to monitor for small fibers of respirable asbestos. 

Samples were collected from the late afternoon on November 8 to the morning of November 9, the afternoon of November 11, and the morning to evening on November 12. Results of the analysis showed no asbestos. Reports Can be found below.

November 8/9 report: Asbestos TEM Analysis

November 11 report: Asbestos Analysis 

November 12 reports: Report 1 (

November 12 reports: Report 2 (

Samples were taken on 11/8 using glass plates, which were used to capture fallout materials from the fire and were tested for asbestos. The samples were taken at four locations: Veterans Sports Park, OC Sherriff’s Regional Training Center, Legacy Magnet Academy and Amalfi Apartments. Two of the four samples (Veterans Sports Park and Amalfi Apartments) were identified to likely contain trace levels of asbestos fibers. See the final report: FINAL REPORT.

South Coast AQMD also collected air samples on November 7 near the hangar and in nearby communities which are being analyzed in our laboratory for gaseous air toxics, such as benzene. Results from these samples show all levels to be within common background levels (air quality on a typical day). The laboratory report can be found here


Mobile Monitoring

On the day of the fire, South Coast AQMD deployed its mobile monitor to take measurements of metals, including lead and arsenic. The majority of results from the mobile monitoring showed no elevated levels of metals. For short periods of time on November 7, the mobile monitor showed elevations of lead and arsenic inside the area of the smoke plume. Mobile monitoring on November 8 did show some elevated levels of lead, but the levels were five times lower than those observed during the fire.   

Additional metal measurements were completed on November 11 and 12. A majority of results showed no elevated levels of metals. Some elevated levels of lead and arsenic were detected inside the area of the smoke plume.    


AQMD Website

South Coast AQMD Mobile Application
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