Maui Air Monitoring and Sampling Shows Good Air Quality

Posted on Dec 7, 2023 in Newsroom

HONOLULU – The Hawaiʻi Department of Health (DOH) continues to monitor air quality in wildfire-impacted areas of Maui. 

“DOH will continue both real-time air monitoring and air sampling to provide the community with data on whether debris removal or other activities are impacting air quality,” said Deputy Director for Environmental Health Kathleen Ho. “It’s important to remember that air monitoring and sampling are indicative of the ambient air quality at the time the samples were collected. Cleanup activities could cause hazardous dust and ash to become airborne. When in the impacted area where exposure risk is high, people should wear a well-fitting N95 or higher-rated mask and other personal protective equipment. 

DOH and the U.S. Environmental Protection Agency have installed 53 real-time air monitors in Lahaina and Upcountry Maui—data from these monitors is available at The real-time monitors measure for PM 2.5, particulate matter that is 0.0025 millimeters and smaller in size (about 30 times smaller than a human hair) that can be a component of ash, dust, smoke, and air pollution. 

Contaminants of concern, such as metals like lead or arsenic, stick to the pieces of ash and dust that register as PM 2.5. Because of this, air monitoring for PM 2.5 can be used as an indicator for contaminant monitoring. If PM 2.5 measurements are not above typical baseline levels, then ash and dust from the impacted areas with their associated contaminants, are not in the air in any measurable amount that would be considered harmful. Elevated PM 2.5 readings could also be attributed to car exhaust, chimney smoke, outdoor cooking/smoking of food, and activities like yard work and wood chipping. 

DOH is also conducting air monitoring and air sampling in Kula as the U.S. Army Corps of Engineers (USACE) conducts Phase II debris removal. Air sampling is conducted 24 hours a day for specific contaminants. After the sampling is completed, samples are sent to a certified laboratory for analysis. 

This sampling is being conducted to ensure that the USACE debris removal activities do not significantly impact air quality in the area of Kula and will continue throughout the debris removal work.

Air monitoring, sampling, and testing are being conducted for PM 2.5, PM 10, asbestos, and metals, including antimony, arsenic, barium, beryllium, cadmium, chromium, cobalt, copper, lead, manganese, molybdenum, nickel, selenium, thallium, vanadium, and inc.

Air monitoring and sampling conducted between November 8, 2023, and November 15, 2023, shows good air quality.

  • There were no asbestos sample results above the laboratory’s detection limit, indicating asbestos fibers were not present in the sampled air. 
  • Some heavy metal sample results were below the laboratory’s detection limit. Low levels of other heavy metals were detected, but all are below the public health screening levels indicating that the detections do not impact human health. 
  • Particulate matter screening levels were elevated at one Kula sampling point which can be attributed to the operation of woodchippers and the spreading of woodchips on, and adjacent to, the property where the air monitor is located. The exceedances are not attributable to the USACE Phase II debris removal activities.

Click here to view the Kula air sampling data:

Similar air sampling will be conducted by DOH in Lahaina when Phase II removal activities begin.