HYBRID - Our Initiatives > Healthy Air > Outdoor > Fighting For Healthy Air | American Lung Association

Kilauea on the Big Island of Hawaii is one of the most active volcanoes in the world. Part of this activity is the production and release of gases mixed with water and tiny particles such as sulfur compounds to form VOG. One of the gases released by Kilauea is sulfur dioxide (SO2). The SO2 reacts with other chemicals in the air to form both liquid and solid particulate pollution. The particles scatter light, making the air appear hazy. It is this pollution that we see and call VOG. SO2 levels in vog are greatest close to the volcano. These chemicals are irritating to the eyes, nose, throat and lungs.

Kilauea also produces tons of lava every day. When the lava flows into the ocean, the intense heat evaporates the water, vaporizing salts at the same time. As the water vapor cools, the salts recombine and hydrogen chloride is formed. This reacts with water to form droplets of hydrochloric acid. The droplets scatter light forming a haze we call LAZE.

The VOG is moved away from Kilauea by wind. The wind direction determines which part of Hawaii will be affected. When the prevailing, northeasterly tradewinds are blowing, VOG collects on the Kona side of the Big Island before being blown out to sea. When southerly (Kona) winds are blowing, VOG affects the Hilo side of the Big Island and may blow up to impact islands farther up the chain.  Learn mor about VOG

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