State: Take precautionary measures against vog caused by Kīlauea eruption

Kīlauea volcano on the Big Island erupted Dec. 23, 2024, in its summit caldera within Hawai’i Volcanoes National Park and has continued to erupt episodically since, so far with 11 eruptive episodes of lava foutains and flows from two vents in the southwest portion of Halema’uma’u Crater.

In fact, what Hawaiian Volcano Observatory called “rootless” lava flows continued on the morning of March 1 to encroach on the eastern side of the Halemaʻumaʻu floor and the downdropped block in the northeast corner and south of the September 2023 vents inside the caldera.

The flows appear to be coming through the floor of Halemaʻumaʻu Crater and are not directly associated with the current eruptive vents, which overnight Feb. 28 and into March 1 showed strong intermittent glow.

The ongoing summit eruption technically paused Feb. 26 after just less than 13 hours of fountaining and lava flowing from the two active vents, but volcanic gas emissions remain elevated.

The Hawai’i Department of Health reported Feb. 28 that air quality levels were compromised at several Hawaiʻi Island and Maui locations.

As southerly winds are expected to persist throughout the weekend, particulates in the air and levels of sulfur dioxide could increase and fluctuate in various areas of the state, causing continued and extended poor air quality.

High levels of volcanic gas create vog conditions — hazy air pollution caused by the volcanic emissions — that can have far-reaching effects downwind from the summit. Vog is created as sulfur dioxide is continuously released from the summit during an eruption and reacts with the atmosphere.

Volcanic fragments and other eruption hazards such as Pele’s hair — strands of volcanic glass produced by lava fountaining activity that can cluster together and appear like tumbleweed — also could impact impact Hawai‘i Volcanoes National Park and nearby communities depending on wind conditions.

Residents and visitors alike are encouraged to access the air quality data on the the state Health Department Clean Air Branch website and the Hawai‘i Interagency Vog Information Dashboard for the most comprehensive and up-to-date online information about vog and sulfur dioxide from volcanic activity in Hawai‘i.

People also are urged to be aware of the conditions around them and how they could react to vog in the air.

The following measures are advised in the event of voggy conditions:

• Reduce outdoor activities that cause heavy breathing. This is especially important for sensitive groups such as children, the elderly and individuals with pre-existing respiratory conditions such as asthma, bronchitis, emphysema and chronic lung and heart disease.
• People with asthma or a chronic respiratory disease should always have medications available. Daily prescribed medications should be taken on schedule.
• People experiencing health effects should contact their medical provider as soon as possible if any symptoms develop since respiratory conditions might worsen rapidly in heavy sulfur dioxide or vog conditions.
• Stay indoors and close windows and doors. If using an air conditioner, set it to recirculate. If you need to move out of an impacted area, turn on the car’s air conditioner and set it to recirculate.
• Face masks (surgical, cloth, KF94, KN95, N95) do not provide protection from sulfur dioxide or vog. However, they can be effective in outdoor environments in reducing inhaled hazardous particulates associated with falling ash and Pele’s hair.
• Do not smoke and avoid second-hand smoke.
• Drink plenty of fluids to avoid dehydration.
• Have family emergency plans prepared and ready.
• Heed warnings by county and state emergency management officials.

Vog and air quality updates are available through the:

• Hawaiʻi Interagency Vog Information Dashboard.
• Hawai‘i Department of Health Clean Air Branch.
• U.S. Geological Survey Kīlauea volcano updates.

Hawaiian Volcano Observatory reported the morning of March 1 that based on measurements made during earlier eruptive episodes and pauses, current sulfur dioxide emission rates are likely to be about 1,000 tonnes per day during this pause period.

A sulfur dioxide emission rate of 2,100 tonnes per day was last measured at 11 a.m. Feb. 20.